SCIENTIFIC AMERICAN SUPPLEMENT NO. 433

NEW YORK, APRIL 19, 1884

Scientific American Supplement. Vol. XVII, No. 433.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.

THE FRENCH SCIENTIFIC STATION AT CAPE HORN.

In 1875 Lieutenant Weyprecht of the Austrian navy called the
attention of scientific men to the desirability of having an
organized and continual system of hourly meteorological and
magnetic observations around the poles. In 1879 the first
conference of what was termed the International Polar Congress was
held at Hamburg. Delegates from eight nations were
present–Germany, Austria, Denmark, France, Holland, Norway,
Russia, and Sweden.

The congress then settled upon a programme whose features were:
1. To establish general principles and fixed laws in regard to the
pressure of the atmosphere, the distribution and variation of
temperature, atmospheric currents, climatic characteristics. 2. To
assist the prediction of the course and occurrence of storms. 3. To
assist the study of the disturbances of the magnetic elements and
their relations to the auroral light and sun spots. 4. To study the
distribution of the magnetic force and its secular and other
changes. 5. To study the distribution of heat and submarine
currents in the polar regions. 6. To obtain certain dimensions in
accord with recent methods. Finally, to collect observations and
specimens in the domain of zoology, botany, geology, etc.

The representatives of the various nations had several
conferences later, and by the 1st of May, 1881, there were
sufficient subscribers to justify the establishment of eight Arctic
stations.

France entered actively in this work later, and its first
expedition was to Orange Bay and Cape Horn, under the surveillance
and direction of the Academy of Sciences, Paris, and responsible to
the Secretary of the Navy. On the 6th of September, 1882, this
scientific corps established itself in Orange Bay, near Cape Horn,
and energetically began its serious labors, and by October 22 the
greater part of their preliminary preparations was completed,
comprising the erection of a magnetic observatory, an astronomic
observatory, a room for the determination of the carbonic anhydride
of the air, another for the sea register, and a bridge 92 feet
long, photographic laboratory, barometer room, and buildings for
the men, food, and appurtenances, together with a laboratory of
natural history.

In short, in spite of persistent rains and the difficulties of
the situation, from September 8 to October 22 they erected an
establishment of which the different parts, fastened, as it were,
to the flank of a steep hill, covered 450 square meters (4,823
square feet), and rested upon 200 wooden piles.

From September 26, 1882, to September 1, 1883, night and day
uninterruptedly, a watch was kept, in which the officers took part,
so that the observations might be regularly made and recorded.
Every four hours a series of direct magnetic and meteorological
observations was made, from hour to hour meteorological notes were
taken, the rise and fall of the sea recorded, and these were
frequently multiplied by observations every quarter of an hour; the
longitude and latitude were exactly determined, a number of
additions to the catalogue of the fixed stars for the southern
heavens made, and numerous specimens in natural history
collected.

The apparatus employed by the expedition for the registration of
the magnetic elements was devised by M. Mascart, by which the
variations of the three elements are inscribed upon a sheet of
paper covered with gelatine bromide, inclination, vertical and
horizontal components, with a certainty which is shown by the 330
diurnal curves brought back from the Cape.

The register proper is composed of a clock and a photographic
frame which descends its entire length in twenty-four hours, thus
causing the sensitized paper to pass behind a horizontal window
upon which falls the light reflected by the mirrors of the magnetic
instruments. One of those mirrors is fixed, and gives a line of
reference; the other is attached to the magnetic bar, whose
slightest movements it reproduces upon the sensitized paper. The
moments when direct observations were taken were carefully
recorded. The magnetic pavilion was made of wood and copper,
placed at about fifty-three feet from the dwellings or camp, near
the sea, against a wooded hill which shaded it completely; the
interior was covered with felt upon all its sides, in order to
avoid as much as possible the varying temperatures.

The diurnal amplitude of the declination increased uniformly
from the time of their arrival in September up to December, when it
obtained its maximum of 7’40”, then diminished to June, when it is
no more than 2’20”; from this it increased up to the day of
departure. The maximum declination takes place toward 1 P.M., the
minimum at 8:50 A.M. The night maxima and minima are not clearly
shown except in the southern winter.

The mean diurnal curve brings into prominence the constant
diminution of the declination and the much greater importance of
the perturbations during the summer months. These means, combined
with the 300 absolute determinations, give 4′ as the annual change
of the declination.

M. Mascart’s apparatus proved to be wonderfully useful in
recording the rapid and slight perturbations of the magnet.
Comparisons between the magnetic and atmospheric perturbations gave
no result. There was, however, little stormy weather and no auroral
displays. This latter phenomenon, according to the English
missionaries, is rarely observed in Tierra del Fuego.

The electrometer used at the Cape was founded upon the principle
developed by Sir William Thomson. The atmospheric electricity is
gathered up by means of a thin thread of water, which flows from a
large brass reservoir furnished with a metallic tube 6.5 feet long.
The reservoir is placed upon glass supports isolated by sulphuric
acid, and is connected to the electrometer by a thread of metal
which enters a glass vessel containing sulphuric acid; into the
same vessel enters a platinum wire coming from the aluminum needle.
Only 3,000 observations were given by the photographic register,
due to the fact that the instruments were not fully protected
against constant wet and cold.

Besides these observations direct observations of the
magnetometer were made, and the absolute determination of the
elements of terrestrial magnetism attempted.

On the 17th of November, 1882, a severe magnetic disturbance
occurred, lasting from 12 M. until 3 P.M., which in three hours
changed the declination 42′. The same perturbation was felt in
Europe, and the comparison of the observations in the two
hemispheres will prove instructive.

THE ELECTRIC RAILWAY AT VIENNA.

The total length of this railway, which extended from the
Eiskeller in the Schwimmschul-Allee to the northern entrance of the
Rotunda, was 1528.3 meters; the gauge was 1 meter, and 60 per cent.
of the length consisted of tangents, the remaining 40 per cent.
being mostly curves of 250 meters radius. The gradients, three in
number, were very small, averaging about 1:750.

Two generating dynamos were used, which were coupled in parallel
circuit, but in such a manner that the difference of potential in
both machines remained the same at all times. This was accomplished
by the well known method of coupling introduced by Siemens and
Halske, in which the current of one machine excites the field of
the other.

Although the railroad was not built with a view of obtaining a
high efficiency, an electro-motive force of only 150 volts being
used, a mechanical efficiency of 50 per cent. was nevertheless
obtained, both with one generator and one car with thirty
passengers, as well as with two generators and two cars with sixty
passengers; while with two generators and three cars (two of them
having motors) the same result was shown.

THE ELECTRIC RAILWAY AT VIENNA.

The curves obtained by the apparatus that recorded the current
showed very plainly the action within the machines when the cars
were started or set in motion; at first, the current rose rapidly
to a very high figure, and then declined gradually to a fixed
point, which corresponded to the regular rate of speed. The
tractive power, therefore, increases rapidly to a value far
exceeding the frictional resistances, but this surplus energy
serves to increase the velocity, and disappears as soon as a
uniform velocity is reached.

The average speed, both with one and three cars, was 30
kilometers per hour.–Zeitsch. f. Elektrotechnik.

INSTRUCTION IN MECHANICAL ENGINEERING.

By Professor R. H. THURSTON.

The writer has often been asked by correspondents interested in
the matter of technical and trade education to outline a course of
instruction in mechanical engineering, such as would represent his
idea of a tolerably complete system of preparation for entrance
into practice. The synopsis given at the end of this article was
prepared in the spring of 1871, when the writer was on duty at the
U.S. Naval Academy, as Assistant Professor of Natural and
Experimental Philosophy, and, being printed, was submitted to
nearly all of the then leading mechanical engineers of the United
States, for criticism, and with a request that they would suggest
such alterations and improvements as might seem to them best. The
result was general approval of the course, substantially as here
written. This outline was soon after proposed as a basis for the
course of instruction adopted at the Stevens Institute of
Technology, at Hoboken, to which institution the writer was at
about that time called. He takes pleasure in accepting a suggestion
that its publication in the SCIENTIFIC AMERICAN would be of some
advantage to many who are interested in the subject.

The course here sketched, as will be evident on examination,
includes not only the usual preparatory studies pursued in schools
of mechanical engineering, but also advanced courses, such as can
only be taught in special schools, and only there when an unusual
amount of time can be given to the professional branches, or when
post graduate courses can be given supplementary to the general
course. The complete course, as here planned, is not taught in any
existing school, so far as the writer is aware. In his own lecture
room the principal subjects, and especially those of the first part
of the work, are presented with tolerable thoroughness; but many of
the less essential portions are necessarily greatly abridged. As
time can be found for the extension of the course, and as students
come forward better prepared for their work, the earlier part of
the subject is more and more completely developed, and the advanced
portions are taken up in greater and greater detail, each year
giving opportunity to advance beyond the limits set during the
preceding year.

Some parts of this scheme are evidently introductory to advanced
courses of study which are to be taken up by specialists, each one
being adapted to the special instruction of a class of students
who, while pursuing it, do not usually take up the other and
parallel courses. Thus, a course of instruction in Railroad
Engineering, a course in Marine Engineering, or a course of study
in the engineering of textile manufactures, may be arranged to
follow the general course, and the student will enter upon one or
another of these advanced courses as his talents, interests, or
personal inclinations may dictate. At the Stevens Institute of
Technology, two such courses–Electrical and Marine
Engineering–are now organized as supplementary of the general
course, and are pursued by all students taking the degree of
Mechanical Engineer. These courses, as there given, however, are
not fairly representative of the idea of the writer, as above
expressed, since the time available in general course is far too
limited to permit them to be developed beyond the elements, or to
be made, in the true sense of the term, advanced professional
courses. Such advanced courses as the writer has proposed must be
far more extended, and should occupy the whole attention of the
student for the time. Such courses should be given in separate
departments under the direction of a General Director of the
professional courses, who should be competent to determine the
extent of each, and to prevent the encroachment of the one upon
another; but they should each be under the immediate charge of a
specialist capable of giving instruction in the branch assigned to
him, in both the theoretical and purely scientific, and the
practical and constructive sides of the work. Every such school
should be organized in such a manner that one mind, familiar with
the theory and the practice of the professional branches taught,
should be charged with the duty of giving general direction to the
policy of the institution and of directing the several lines of
work confided to specialists in the different departments. It is
only by careful and complete organization in this, as in every
business, that the best work can be done at least expense in time
and capital.

In this course of instruction in Mechanical Engineering it will
be observed that the writer has incorporated the scheme of a
workshop course. This is done, not at all with the idea that a
school of mechanical engineering is to be regarded as a “trade
school,” but that every engineer should have some acquaintance with
the tools and the methods of work upon which the success of his own
work is so largely dependent. If the mechanical engineer can
acquire such knowledge in the more complete course of instruction
of the trade school, either before or after his attendance at the
technical school, it will be greatly to his advantage. The
technical school has, however, a distinct field; and its province
is not to be confounded with that of the trade school. The former
is devoted to instruction in the theory and practice of a
profession which calls for service upon the men from the
latter–which makes demand upon a hundred trades–in the
prosecution of its designs. The latter teaches, simply, the
practical methods of either of the trades subsidiary to the several
branches of engineering, with only so much of science as is
essential to the intelligent use of the tools and the successful
application of the methods of work of the trade taught. The
distinction between the two departments of education, both of which
are of comparatively modern date, is not always appreciated in the
United States, although always observed in those countries of
Europe in which technical and trade education have been longest
pursued as essential branches of popular instruction. Throughout
France and Germany, every large town has its trade schools, in
which the trades most generally pursued in the place are
systematically taught; and every large city has its technical
school, in which the several professions allied to engineering are
studied with special development of those to which the conditions
prevailing at the place give most prominence and local
importance.

A course of trade instruction, as the writer would organize it,
would consist, first, in the teaching of the apprentice the use of
the tools of his trade, the nature of its materials, and the
construction and operation of the machinery employed in its
prosecution. He would next be taught how to shape the simpler
geometrical forms in the materials of his trade, getting out a
straight prism, a cylinder, a pyramid, or a sphere, of such size
and form as may be convenient; getting lines and planes at right
angles, or working to miter; practicing the working of his “job” to
definite size, and to the forms given by drawings, which drawings
should be made by the apprentice himself. When he is able to do
good work of this kind, he should attempt larger work, and the
construction of parts of structures involving exact fitting and
special manipulations. The course, finally, should conclude with
exercises in the construction and erection of complete structures
and in the making of peculiar details, such as are regarded by the
average workman as remarkable “tours de force.” The trade
school usually gives instruction in the common school branches of
education, and especially in drawing, free-hand and mechanical,
carrying them as far as the successful prosecution of the trade
requires. The higher mathematics, and advanced courses in physics
and chemistry, always taught in schools of engineering, are not
taught in the trade school, as a rule; although introduced into
those larger schools of this class in which the aim is to train
managers and proprietors, as well as workmen. This is done in many
European schools.

As is seen above, the course of instruction in mechanical
engineering includes some trade education. The engineer is
dependent upon the machinist, the founder, the patternmaker, and
other workers at the trades, for the proper construction of the
machinery and structures designed by him. He is himself, in so far
as he is an engineer, a designer of constructions, not a
constructor. He often combines, however, the functions of the
engineer, the builder, the manufacturer, and the dealer, in his own
person. No man can carry on, successfully, any business in which he
is not at home in every detail, and in which he cannot instruct
every subordinate, and cannot show every person employed by him
precisely what is wanted, and how the desired result can be best
attained. The engineer must, therefore, learn, as soon and as
thoroughly as possible, enough of the details of every art and
trade, subsidiary to his own department of engineering, to enable
him to direct, with intelligence and confidence, every operation
that contributes to the success of his work. The school of
engineering should therefore be so organized that the young
engineer may be taught the elements of every trade which is likely
to find important application in his professional work. It cannot
be expected that time can be given him to make himself an expert
workman, or to acquire the special knowledge of details and the
thousand and one useful devices which are an important part of the
stock in trade of the skilled workman; but he may very quickly
learn enough to facilitate his own work greatly, and to enable him
to learn still more, with rapidity and ease, during his later
professional life. He must also, usually, learn the essential
elements and principles of each of several trades, and must study
their relations to his work, and the limitations of his methods of
design and construction which they always, to a greater or less
extent, cause by their own practical or economical limitations. He
will find that his designs, his methods of construction, and of
fitting up and erecting, must always be planned with an intelligent
regard to the exigencies of the shop, as well as to the aspect of
the commercial side of every operation. This extension of trade
education for the engineer into several trades, instead of its
restriction to a single trade, as is the case in the regular trade
school, still further limits the range of his instruction in each.
With unusual talent for manipulation, he may acquire considerable
knowledge of all the subsidiary trades in a wonderfully short space
of time, if he is carefully handled by his instructors, who must
evidently be experts, each in his own trade. Even the average man
who goes into such schools, following his natural bent, may do well
in the shop course, under good arrangements as to time and
character of instruction. If a man has not a natural inclination
for the business, and a natural aptitude for it, he will make a
great mistake if he goes into such a school with the hope of doing
creditable work, or of later attaining any desirable position in
the profession.

The course of instruction, at the Stevens Institute of
Technology, includes instruction in the trades to the extent above
indicated. The original plan, as given below, included such a
course of trade education for the engineer; but it was not at once
introduced. The funds available from an endowment fund crippled by
the levying of an enormous “succession tax” by the United States
government and by the cost of needed apparatus and of unanticipated
expenses, in buildings and in organization, were insufficient to
permit the complete organization of this department. A few tools
were gathered together; but skilled mechanics could not be employed
to take up the work of instruction in the several courses. Little
could therefore be done for several years in this direction. In
1875 the writer organized a “mechanical laboratory,” with the
purpose of attaining several very important objects: the
prosecution of scientific research in the various departments of
engineering work; the creation of an organization that should give
students an opportunity to learn the methods of research most
usefully employed in such investigations; the assistance of members
of the profession, and business organizations in the attempt to
solve such questions, involving scientific research, as are
continually arising in the course of business; the employment of
students who had done good work in their college course, when they
so desire, in work of investigation with a view to giving them such
knowledge of this peculiar line of work as should make them capable
of directing such operations elsewhere; and finally, but not least
important of all, to secure, by earning money in commercial work of
this kind, the funds needed to carry on those departments of the
course in engineering that had been, up to that time, less
thoroughly organized than seemed desirable. This “laboratory” was
organized in 1875, the funds needed being obtained by drawing upon
loans offered by friends of the movement and by the “Director.”

It was not until the year 1878, therefore, that it became
possible to attempt the organization of the shop course; and it was
then only by the writer assuming personal responsibility for its
expenses that the plan could be entered upon. As then organized–in
the autumn of 1878–a superintendent of the workshop had general
direction of the trade department of the school. He was instructed
to submit to the writer plans, in detail, for a regular course of
shop instruction, and was given as assistants a skilled mechanic of
unusual experience and ability, whose compensation was paid from
the mechanical laboratory funds, and guaranteed by the writer
personally, and another aid whose services were paid for partly by
the Institute and partly as above. The pay of the superintendent
was similarly assured. This scheme had been barely entered upon
when the illness of the writer compelled him to temporarily give up
his work, and the direction of the new organization fell into other
hands, although the department was carried on, as above, for a year
or more after this event occurred.

The plan did not fall through; the course of instruction was
incorporated into the college course, and its success was finally
assured by the growth of the school and a corresponding growth of
its income, and, especially, by the liberality of President Morton,
who met expenses to the amount of many thousands of dollars by
drawing upon his own bank account. The department was by him
completely organized, with an energetic head, and needed support
was given in funds and by a force of skilled instructors. This
school is now in successful operation. This course now also
includes the systematic instruction of students in experimental
work, and the objects sought by the writer in the creation of a
“mechanical laboratory” are thus more fully attained than they
could have possibly been otherwise. It is to be hoped that, at some
future time, when the splendid bequest of Mr. Stevens may be
supplemented by gifts from other equally philanthropic and
intelligent friends of technical education, among the alumni of the
school and others, this germ of a trade school maybe developed into
a complete institution for instruction in the arts and trades of
engineering, and may thus be rendered vastly more useful by meeting
the great want, in this locality, of a real trade school, as well
as fill the requirements of the establishment of which it forms a
part, by giving such trade education as the engineer needs and can
get time to acquire.

The establishment of advanced courses of special instruction in
the principal branches of mechanical engineering may, if properly
“dovetailed” into the organization, be made a means of somewhat
relieving the pressure that must be expected to be felt in the
attempt to carry out such a course as is outlined below. The
post-graduate or other special departments of instruction, in
which, for example, railroad engineering, marine engineering, and
the engineering of cotton, woolen, or silk manufactures, are to be
taught, may be so organized that some of the lectures of the
general course may be transferred to them, and the instructors in
the latter course thus relieved, while the subjects so taught,
being treated by specialists, may be developed more efficiently and
more economically.

Outlines of these advanced courses, as well as of the courses in
trade instruction comprehended in the full scheme of mechanical
engineering courses laid out by the writer a dozen years ago, and
as since recast, might be here given, but their presentation would
occupy too much space, and they are for the present omitted.

The course of instruction in this branch of engineering, at the
Stevens Institute of Technology, is supplemented by “Inspection
Tours,” which are undertaken by the graduating class toward the
close of the last year, under the guidance of their instructors, in
which expeditions they make the round of the leading shops in the
country, within a radius of several hundred miles, often, and thus
get an idea of what is meant by real business, and obtain some
notion of the extent of the field of work into which they are about
to enter, as well as of the importance of that work and the
standing of their profession among the others of the learned
professions with which that of engineering has now come to be
classed.

At the close of the course of instruction, as originally
proposed, and as now carried out, the student prepares a
“graduating thesis,” in which he is expected to show good evidence
that he has profited well by the opportunities which have been
given him to secure a good professional education. These theses are
papers of, usually, considerable extent, and are written upon
subjects chosen by the student himself, either with or without
consultation with the instructor. The most valuable of these
productions are those which present the results of original
investigations of problems arising in practice or scientific
research in lines bearing upon the work of the engineer. In many
cases, the work thus done has been found to be of very great value,
supplying information greatly needed in certain departments, and
which had previously been entirely wanting, or only partially and
unsatisfactorily given by authorities. Other theses of great value
present a systematic outline of existing knowledge of some subject
which had never before been brought into useful form, or made in
any way accessible to the practitioner. In nearly all cases, the
student is led to make the investigation by the bent of his own
mind, or by the desire to do work that may be of service to him in
the practice of his profession. All theses are expected to be made
complete and satisfactory to the head of department of Engineering
before his signature is appended to the diploma which is finally
issued to the graduating student. These preliminaries being
completed, and the examinations having been reported as in all
respects satisfactory, the degree of Mechanical Engineer is
conferred upon the aspirant, and he is thus formally inducted into
the ranks of the profession.

COURSE OF INSTRUCTION IN MECHANICAL ENGINEERING.

Robert H. Thurston–July, 1871.

I.

MATERIALS USED IN ENGINEERING.–Classification, Origin, and
Preparation (where not given in course of Technical Chemistry),
Uses, Cost.

Strength and Elasticity.–Theory (with experimental
illustrations), reviewed, and tensile, transverse and torsional
resistance determined.

Forms of greatest strength determined. Testing
materials.

Applications.–Foundations, Framing in wood and
metal.

FRICTION.–Discussion from Rational Mechanics, reviewed and
extended.

Lubricants treated with materials above.

Experimental determination of “coefficients of friction.”

II.

TOOLS.–Forms for working wood and metals. Principles involved
in their use.

Principles of pattern making, moulding, smith and machinists’
work so far as they modify design.

Exercises in Workshops in mechanical manipulation.

Estimates of cost (stock and labor).

MACHINERY AND MILL WORK.–Theory of machines. Construction.
Kinematics applied. Stresses, calculated and traced. Work of
machines. Selection of materials for the several parts.
Determination of proportions of details, and of forms
as modified by difficulties of construction.

Regulators, Dynamometers, Pneumatic and Hydraulic machinery.
Determining moduli of machines.

POWER, transmission by gearing, belting, water, compressed air,
etc.

LOADS, transportation.

III.

HISTORY AND PRESENT FORMS OF THE PRIME MOVERS.

Windmills, their theory, construction, and
application.

Water Wheels. Theory, construction, application, testing,
and comparison of principal types.

Air, Gas, and Electric Engines, similarly treated.

STEAM ENGINES.–Classification. [Marine (merchant) Engine
assumed as representative type.] Theory. Construction, including
general design, form and proportion of details.

Boilers similarly considered. Estimates of
cost.

Comparison of principal types of Engines and Boilers.
Management and repairing. Testing and recording performance.

IV.

MOTORS APPLIED to Mills. Estimation of required power and of
cost.

Railroads. Study of Railroad machinery.

Ships. Structure of Iron Ships and rudiments of Naval
architecture and Ship propulsion.

PLANNING Machine shops, Boiler shops, Foundries, and
manufactories of textile fabrics. Estimating cost.

LECTURES BY EXPERTS.

GENERAL SUMMARY of principal facts, and natural laws, upon the
thorough knowledge of which successful practice is based; and
general resume of principles of business which must be
familiar to the practicing engineer.

V.

GRADUATING THESES.

GRADUATION.

Accompanying the above are courses of instruction in higher
mathematics, graphics, physics, chemistry, and the modern languages
and literatures.

IMPROVED DOUBLE BOILER.

The operation of boiling substances under pressure with more or
less dilute sulphuric or sulphurous acid forms a necessary stage of
several important manufactures, such as the production of paper
from wood, the extraction of sugar, etc. A serious difficulty
attending this process arises from the destructive action of the
acid upon the boiler or chamber in which the operation is carried
on, and as this vessel, which is generally of large dimensions, is
exposed to considerable pressures, it is necessarily constructed of
iron or some other sufficiently resisting metal. An ingenious
method of avoiding this difficulty has been devised, we believe in
Germany, and has been put into practice with a certain amount of
success. It consists in lining the iron boiler with a covering of
lead, caused by fusion to unite firmly to the walls of the boiler,
and thus to protect it from the action of the acid. No trouble, it
is stated, is found to arise from the difference in expansion of
the two metals, which, moreover, adhere fairly well; but, on the
other hand, we believe it does actually occur that the repairs to
this lead lining are numerous, tedious, and costly of execution, so
that the system can scarcely be regarded as meeting the
requirements of the manufacturer. It is to secure all the
advantages possessed by a lead-lined vessel, without the drawback
of frequent and expensive repairs, that the digester, of which we
annex illustrations, has been devised by Mr. George Knowles, of
Billiter House, Billiter Street. It consists of a closed iron
cylindrical vessel suitable for boiling under pressure, and
containing a second vessel open at the top, and of such a diameter
as to leave an annular space between it and the walls of the outer
shell. This inner receiver, which may be made of lead, glass,
pottery, or any other suitable material, contains the substance to
be treated and the sulphurous acid or other solution in which it is
to be boiled. The annular space between the two vessels is filled
with water to the same level as the solution in the receiver, and
the latter is provided with suitable pipes or coils, in which steam
is caused to circulate for the purpose of raising the solution of
the desired temperature, and effecting the digesting process. At
the same time any steam generated collects in the upper part of the
boiler, and maintains an equal pressure within the whole apparatus.
Figs. 1 to 3 show the arrangement clearly. Within the boiler, a, is
placed the receiver, b, of pottery, lead, or other material,
leaving an annular space between it and the boiler; this space is
filled with water. The receiver, b, is furnished with a series of
pipes, in which steam or hot water circulates, to heat the charge
to the desired temperature. These pipes may be arranged either in
coils, as shown at d, Fig. 1, or vertically at d, Fig. 3. The
latter are provided with inner return pipes, so that any condensed
water accumulating at the bottom may be forced up the inner pipes
by the steam pressure and escape at the top. The vessel is charged
through the manhole, e, and the hopper, c, provided with a
perforated cover, and is discharged at the bottom by the valve, f,
shown in Figs. 2 and 3. The upper part of the boiler serves as a
steam dome, and the pressure on the liquid in the receiver and on
the water in the annular space is thereby maintained uniform. The
necessary fittings for showing the pressure in the vessel, water
level indicator, safety valve, cocks for testing solutions, etc.,
are of course added to the apparatus, but are not indicated in the
drawing. The arrangement appears to us to possess considerable
merit, and we shall refer to it again on another occasion, after
experiments have been made to test its
efficiency.–Engineering.

IMPROVED DOUBLE BOILER.

THE GARDNER MACHINE GUN.

FIG. 1.–SINGLE BARREL GARDNER MACHINE GUN.

The mechanism by which the various functions of loading, firing,
and extracting are performed is contained in a rectangular gun
metal case, varying in dimensions with the number of barrels in the
arm. In the single barrel gun the size of this case is 14 inches in
length, 5½ inches in depth, and 2½ inches in width.
The top of the box is hinged, so that easy access can be had to the
mechanism, which consists of a lock, the cartridge carrier, and the
devices for actuating them. In the multiple barrel guns, the frames
which, with the transverse bar at the end, hold the barrels in
place, form the sides of the mechanism chamber, in the front end of
which the barrels are screwed. The mechanism is actuated by a cam
shaft worked by a hand crank on one side of the chamber. By this
means the locks are driven backward and forward, the latter motion
forcing the cartridges into place, and the former withdrawing the
empty cartridge case after firing. The extractor hook pivoted to
the lock plunger rises, as the lock advances, over the rim of the
case, but is rigid as the lock is withdrawn, so that the action is
a positive one. The cartridges, which are contained in a suitable
frame attached to the forward part of the breech chamber, pass
through openings in the top plate of the latter, an efficient
distribution being secured by means of a valve having a transverse
motion. Each cartridge as it falls is brought into the axis of the
barrel and the plunger, while the advance motion of the lock forces
them into position. In the five-barrel gun illustrated by Fig. 3
the cartridge feeder contains 100 cartridges, in five Vertical rows
of 20 cartridges each, and these are kept supplied, when firing,
from supplementary holders. Fig. 1 shows the portable rest
manufactured by the Gardner Gun Company. It consists of two wrought
iron tubes, placed at right angles to each other; the front bar can
be easily unlocked, and placed in line with the trail bar, from
which project two arms, each provided with a screw that serves for
the lateral adjustment of the gun. These screws are so arranged as
to allow for an oscillating motion of the gun through any distance
up to 15 deg. The tripod mounting, used for naval as well as land
purposes, is shown in Fig. 2, which illustrates the two barrel gun
complete. The five barrel gun, Fig. 3, is shown mounted on a
similar tripod. The length of this weapon over all is 53.5 inches,
the barrels (Henry system) are 33 inches long, with seven grooves
of a uniform twist of one turn in 22 inches.

Fig. 2.–TWO BARREL GARDNER GUN.

Gardener’s five barrel gun in the course of one of the trials
fired 16,754 rounds with only 24 jams, and in rapid firing reached
a maximum of 330 shots in 30 seconds. The two barrel gun fired
6,929 rounds without any jam; the last 3,000 being in 11 minutes 39
seconds, without any cleaning or oiling.–Engineering.

Fig. 3.–FIVE BARREL GARDNER GUN.

CLIMBING TRICYCLES.

The cycle trade is one which has been developed with great
rapidity within the last ten years, and, like all new industries,
has called forth a considerable amount of ingenuity and skill on
the part of those engaged in it. We cannot help thinking, however,
that much of this ingenuity has been misplaced, and that instead of
striving after new forms involving considerable complication and
weight, it would have been better and more profitable if
manufacturers had moderated their aspirations, and aimed at greater
simplicity of design; for it must be remembered that cyclists are,
as a rule, without the slightest mechanical knowledge, while the
machines themselves are subject to very hard usage and considerable
wear and tear in traveling over the ordinary roads in this country.
We refer, of course, more especially to tricycles, which in one
form or another are fast taking the place of bicycles, and which
promise to assume an important position in every day locomotion.
Hitherto one of the chief objections to the use of the tricycle has
been the great difficulty experienced in climbing hills, a very
slight ascent being sufficient to tax the powers of the rider to
such an extent as to induce if not compel him in most instances to
dismount and wheel his machine along by hand until more favorable
ground is reached. To obviate this inconvenience many makers have
introduced some arrangement of gearing speeds of two powers giving
the necessary variation for traveling up hill and on the level. We
noticed, however, one machine at the exhibition which seemed to
give all that could be desired without any gearing or chains at
all. This was a direct action tricycle shown by the National Cycle
Company, of Coventry, in which the pressure from the foot is made
to bear directly upon the main axle, and so transmitted without
loss to the driving wheels on each side, the position of the rider
being arranged so that just sufficient load is allowed to fall on
the back wheel as to obtain certainty in steerage. The weight of
this machine is much less than when gearing is used, and the
friction is also considerably reduced, trials with the dynamometer
having shown that on a level, smooth road, a pull of 1 lb. readily
moved it, while with a rider in the seat 4 lb. was sufficient. On
this tricycle any ordinary hill can, it is stated, be ascended with
great ease, and as a proof of its power it was exhibited at the
Stanley show climbing over a piece of wood 8 in. high, without any
momentum whatever. We understand that at the works at Coventry a
flight of stairs has been erected, and that no difficulty is
experienced in ascending them on one of these machines.–The
Engineer.

SUBMARINE EXPLORATIONS.

VOYAGE OF THE TALISMAN.

It was but a few years ago that the idea was prevalent that the
seas at great depths were immense solitudes where life exhibited
itself under no form, and where an eternal night reigned. To-day,
thanks to expeditions undertaken for the purpose of exploring the
abysses of the ocean, we know that life manifests itself abundantly
over the bottom, and that at a depth of five and six thousand
meters light is distributed by innumerable phosphorescent animals.
Different nations have endeavored to rival each other in the effort
to effect these important discoveries, and several scientific
missions have been sent to different points of the globe by the
English and American governments. The French likewise have entered
with enthusiasm upon this new line of research, and for four
consecutive years, thanks to the devoted aid of the ministry of the
marine, savants have been enabled to take passage in government
vessels that were especially arranged for making submarine
explorations.

THE FRENCH SCIENTIFIC STEAMER TALISMAN.

The first French exploration, which was an experimental trip,
was made in 1880 by the Travailleur in the Gulf of Gascogne. Its
unhoped for results had so great an importance that the following
year the government decided to continue its researches, and the
Travailleur was again put at the disposal of Mr. Alph. Milne
Edwards and the commission over which he presided. Mr. Edwards
traversed the Gulf of Gascogne, visited the coast of Portugal,
crossed the Strait of Gibraltar, and explored a great portion of
the Mediterranean. In 1882 the same vessel undertook a third
mission to the Atlantic Ocean, and as far as to the Canary Islands.
The Travailleur, however, being a side-wheel advice-boat designed
for doing service at the port of Rochefort, presented none of those
qualities that are requisite for performing voyages that are
necessarily of long duration. The quantity of coal that could be
stored away in her bunkers was consumed in a week, and, after that,
she could not sail far from the points where it was possible for
her to coal up again. So after her return Mr. Edwards made a
request for a ship that was larger, a good sailer, and that was
capable of carrying with it a sufficient supply of fuel for
remaining a long time at sea, and that was adapted to submarine
researches. The Commission indorsed this application, and the
Minister of Instruction received it and transmitted it to Admiral
Jauréguiberry–the Minister of the Marine–who at once gave
orders that the Talisman should be fitted up and put in commission
for the new dredging expedition. This vessel, under command of
Captain Parfait, who the preceding year had occupied the same
position on the Travailleur, left the port of Rochefort on the 1st
of June, 1883, having on board Mr. Milne Edwards and the scientific
commission that had been appointed by the Minister of Public
Instruction. The Talisman explored the coasts of Portugal and
Morocco, visited the Canary and Cape Verd Islands, traversed the
Sea of Sargasso, and, after a stay of some time at the Azores,
returned to France, after exploring on its way the Gulf of Gascogne
(Fig.).

FIG.1.–CHART OF THE TALISMAN’S VOYAGE.

The magnificent collections in natural history that were
collected on this cruise, and during those of preceding years made
by the Travailleur, are, in a few days, to be exhibited at the
Museum of Natural History. We think we shall be doing a service to
the readers of this journal, in giving them some details as to the
organization of the Talisman expedition as well as to the manner in
which the dredgings were performed.

FIG.2.–PLAN OF THE VESSEL.

The vessel, as shown by her plan in Fig. 2, had to undergo
important alterations for the cruise that she was to undertake. Her
deck was almost completely freed from artillery, since this would
have encumbered her too much. Immediately behind the bridge, in the
center of the vessel, there were placed two windlasses, one, A, to
the right, and the other, B, to the left (Fig. 2). These machines,
whose mode of operation will be explained further along, were to
serve for raising and lowering the fishing apparatus. A little
further back there were constructed two cabins, G and HH. The first
of these was designed to serve as a laboratory, and the second was
arranged as quarters for the members of the mission.

The sounding apparatus, the Brothergood engine for actuating it,
and the electric light apparatus were placed upon the bridge. The
operating of the sounding line and of the electric light was
therefore entirely independent of that of the dredges. On the
foremast, at a height of about two meters, there was placed a
crane, F, which was capable of moving according to a horizontal
plane. Its apex, as may be seen from the plan of the boat, was
capable of projecting beyond the sides of the ship, to the left and
right. To this apex was fixed a pulley over which ran the cable
that supported the dredges or bag-nets, which latter were thus
carried over the boat’s sides.

FIG.3.–DIAGRAM OF THE THIBAUDIER SOUNDING
APPARATUS.

The preliminary operation in every submarine exploration
consists in exactly determining the depth of the sea immediately
beneath the vessel. To effect this object different sounding
apparatus have been proposed. As the trials that were made of these
had shown that each of them possessed quite grave defects, Mr.
Thibaudier, an engineer of the navy, installed on board the
Talisman last year a new sounding apparatus which had been
constructed according to directions of his and which have given
results that are marvelous. The apparatus automatically registers
the number of meters of wire that is paid out, and as soon as the
sounding lead touches bottom, it at once stops of itself. This
apparatus is shown in Fig. 4, and a diagram of it is given in Fig.
3, so that its operation may be better understood. The Thibaudier
sounding apparatus consists of a pulley, P (Fig. 3), over which is
wound 10,000 meters of steel wire one millimeter in diameter. From
this pulley, the wire runs over a pulley, B, exactly one meter in
circumference; from thence it runs to a carriage, A, which is
movable along wooden shears, runs up over a fixed pulley, K, and
reaches the sounding lead, S, after traversing a guide, g, where
there is a small sheave upon which it can bear, whatever be the
inclination of the boat. The wheel, B, carries upon its axle an
endless screw that sets in motion two toothed wheels that indicate
the number of revolutions that it is making. One of these marks the
units and the other the hundredths (Fig. 5). This last is graduated
up to 10,000 meters. As every revolution of the wheel, B,
corresponds to one meter, the number indicated by the counter
represents the depth. Upon the axle of the winding pulley there is
a break pulley, p. The brake, f, is maneuvered by a lever, L, at
whose extremity there is a cord, C, which is made fast to the
carriage, A. When, during the motions due to rolling, the tension
of the steel wire that supports the lead diminishes or increases,
the carriage slightly rises or falls, and, during these motions,
acts more or less upon the brake and consequently regulates the
velocity with which the wire unwinds. When the lead touches bottom,
the wire, being suddenly relieved from all weight (which is
sometimes as much as 70 kilos), instantly stops.

FIG. 4.–GERNERAL VIEW OF THE SOUNDING APPARATUS IN
THE “TALISMAN:”

The maneuver of this apparatus may be readily understood. The
apparatus and its weights are arranged in the interior of the
vessel. A man bears upon the lever, L (Fig. 3), and the counter is
set at zero. All being thus arranged, the man lets go of the break,
and the unwinding then proceeds until the lead has touched bottom.
During the operation of sounding, the boat is kept immovable by
means of its engine, so that the wire shall remain as vertical as
possible. The bottom being reached, the unwinding suddenly ceases,
and there is nothing further to do but read the indication given by
the differential counter, this giving the depth.

FIG. 5.–APPARATUS FOR MEASURING THE LENGTH OF THE
WIRE PAID OUT.

Near the winding pulley, there is a small auxiliary engine, M,
which is then geared with the axle of the said pulley, and which
raises the sounding apparatus that has been freed from its weight
by a method that will be described further along.

We have endeavored in Fig. 4 to show the aspect of the bridge at
the moment when a sounding was about being made. From this
engraving (made from a photograph) our readers may obtain a clear
idea of the Thibaudier sounding apparatus, and understand how the
wheel over which the wire runs is set in motion by the Brothergood
engine.–La Nature.

CABLE GRAPNEL.

Some improvements have recently been made by Mr. Alexander Glegg
and the inventor in the well-known Jamieson grapnel used for
raising submerged submarine cables. The chief feature of the
grapnel is that the flukes, being jointed at the socket, bend back
against a spring when they catch a rock, until the grapnel clears
the obstruction, but allow the cable to run home to the crutch
between the fluke and base, as shown in the figures. In the older
form the cable was liable to get jammed, and cut between the fixed
toe or fluke and the longer fluke jointed into it. This is now
avoided by embracing the short fluke within the longer one. The
shank, formerly screwed into the boss, is now pushed through and
kept up against the collar of the boss, by the volute spring, which
at the same time presses back the hinged flukes after being
displaced by a rock. The shank can now freely swivel round, whereas
before it was rigidly fixed. The toes or flukes are now made of
soft cast steel, which can be straightened if bent, and the boss is
made of cast steel or gun-metal.

JAMIESON’S GRAPNEL.

WRETCHED BOILERMAKING.

To the Editor of the Scientific American:

As long as I have been a reader of the SCIENTIFIC AMERICAN I
have been pleased with the manner in which you investigate and
explain the cause of any boiler explosion which comes to your
knowledge; and I have rejoiced when you heaped merited censure upon
the fraudulent boilermaker. In your paper in December last you
copied a short article on “Conscience in Boilermaking,” in which
the writer, after speaking of the tricks of the boilermaker in
using thinner iron for the center sheets than for the others, and
in “upsetting” the edges of the plates to make them appear thicker,
goes on to say: “We call attention to this, because the discovery
of such practice has made serious trouble between the boilermaker
and the steam user. We would not believe that there were men so
blind to the duties and obligations which rest upon them as to
resort to such practice, but the careful inspector finds all such
defects, and in time we come to know whose work is carefully and
honestly done, and whose is open to suspicion. In States and cities
where inspection laws are in force that give the methods and rules
by which the safe working pressure of a boiler is calculated, there
is no alternative except to follow the rules; and if certain
requirements regarding construction are a part of the law, there is
no authority or right to depart from it, and yet there are
boilermakers who try to force their boilers into such localities
when their work is not up to the requirements of the law.”

Now, if some boilermakers are so dishonest as to try and impose
upon the locomotive engineer, who they know will carefully examine
every part of his boiler, and who is able to detect any flaw, it is
not to be expected that the farmer will escape. Nor does he. The
great number of explosions of boilers used in thrashing and in
other farm work proves that there are boilermakers who “force their
boilers into such localities when their work is not up to the
requirements of the law.” And the boilermaker, if he be dishonest,
is doubly tempted if the broad width of a continent intervenes
between him and the farmer for whom his work is intended, and if in
the place where the boiler is to be used there are no inspection
laws in force. The farmer who lives many miles from a city, and who
has no means of testing any boiler he may purchase, is wholly at
the mercy of the boilermaker, and must run it until it explodes or
time proves it to have been honestly made. Then, again, there are
boilermakers who, although making boilers of good iron and of the
proper thickness, finish them off so badly that the farmer is put
to great inconvenience and expense to put them in working order.
Two years ago I purchased a straw-burning engine and boiler made by
an Eastern firm. Before it had run ten days the boiler began to
leak at the saddle-bolt holes. The engineer tightened the nuts as
far as possible, but could not stop the leaks, which at last became
so bad that we had to stop work and take the engine to the shop.
Upon taking off the saddle and taking out the bolts it was
discovered that they were too small for the holes in the boiler,
and that they had been wrapped with candle wick and white lead to
make them fill the holes, and that a light washer had been put on
each bolt between the head and the inside of the boiler. This
washer kept the lead in its place, and prevented the boiler from
showing a leak when first fired up. The water pipes in the fire-box
soon gave out and became utterly useless. Upon inquiring of the
patentee of this straw-burning device, who was supposed to have put
it in my boiler, he stated that he had had nothing to do with it,
but that it was put in by the firm selling these engines, and “as
cheaply as possible.” Before I got this boiler and engine in fair
running order I had spent hundreds of dollars and had to do
entirely away with the water grates.

Last summer, needing another tharshing engine, I was induced to
buy one of the same make as my old one, but with a different
straw-burning device. The firm who sold it to me agreed that it
should have none of the faults of the old one. Well, I got it, and,
upon hauling it out to my ranch, and getting up steam, I found it
to be much worse than the first one I had bought. The boiler leaked
at nearly every hole where a tap had been screwed into it. It took
an engineer, a boilermaker, a blacksmith, and a fireman several
days to get it in shape so that we could use it at all; and after
we did start up, the boilermaker had to be sent for several times
to stop new leaks that were continually showing themselves.

I send you by this mail for your inspection one of the saddle
bolts and one of the bolts taken out of the piston, and also the
certificates of the engineer, boilermaker, and machinist who
repaired the boiler. In justice to my fellow-farmers I ought to
publish these certificates and the names of these boilermakers to
the world, but, for the present at least, I refrain from so doing.
These boilermakers will see this article and they will know, if the
public does not, for whom it is intended. If it has the effect of
making them exercise more care in the construction and fitting up
of their engines and boilers, I have not written in vain.

D. FREEMAN.

Los Angeles, Cal., March 7,1884.

[The two bolts and the certificates above referred to accompany
the letter of Mr. Freeman. We can only wonder how it was that,
after having been treated as he relates in the first instance, he
should have had any further business with parties who would send
out such boilers, for the testimony of the engineer and workmen
make the case even stronger than Mr. Freeman has put it.–ED.]

A THREADED SET COLLAR.

There are cases where a long screw must be rotated with a
traversing nut or other threaded piece traveling on its thread a
limited and variable distance. At one time the threaded nut or
piece may be required to go almost the entire length of the screw,
and at another time a much shorter traverse would be required. In
many instances the use of side check nuts is inconvenient, and in
some it is impossible. One way of utilizing the nut as a set collar
is to drill through its side for a set screw, place it on its
screw, pour a little melted Babbitt metal, or drop a short, cold
plug of it into the hole, tap the hole, and the tap will force the
Babbitt into the threads.

Insert the set screw, and when it acts on the Babbitt metal it
will force it with great friction on to the thread without injuring
the thread; and when the set screw tension is released, the nut
turns freely. A similar and perhaps a better result may be obtained
by slotting the hole through the nut as though for the reception of
a key. Secure a key (preferably of the same material as the nut) by
slight upsetting at its ends, and then thread the nut, key, and
all. Place a set screw through the nut over the threaded key, and
the job is complete.

PNEUMATIC MALTING.

The lethargy in the malting trade, and in all matters relating
to malting processes, induced by two centuries of restrictive
legislation, is being gradually shaken off by the malting industry
under the new law. For many years nearly all improvements in
malting processes originated abroad, as numberless Acts of
Parliament fettered every process and the use of every implement
requisite in a malt-house in this country. The entire removal of
these legislative restrictions gives an opportunity for improved
processes, which promises to open up a considerable field for
engineering work, and to develop a very backward art by the
application of scientific principles. The present time is,
therefore, one of more material change than malting has ever
experienced.

PNEUMATIC MALTING AT TROYES. Fig. 1.

Of the numerous improvements effected in the past few years,
those made by M. Galland in France, and more recently by M.
Saladin, are by far the most prominent. M. Galland originated what
is known as the pneumatic system eight or nine years ago. This
system is carried out at the Maxéville brewery, near
Nancy.

PNEUMATIC MALTING AT TROYES. Fig. 2.

Since that time further improvements have been made by M.
Galland; but more recently great advances have been made in the
system by M. Saladin. He has developed the practice of the leading
principle, and in conjunction with Mr. H. Stopes, of London, has
added improved kilns and various mechanical apparatus for
performing the work previously done by hand. He has also devised a
very ingenious machine for cooling the moist air by which the
process is carried on.

FIG. 4.–ECHANGEUR AND TURNING MACHINE.

At the recent Brewery Exhibition, some of the machinery used in
these new maltings was shown in action by Messrs. H. Stopes &
Co., together with drawings of a malting constructed at Troyes for
M. Bonnette under M. Saladin’s instructions. This malting is the
third constructed for the same firm, the others being at Nancy.
That at Troyes we now illustrate. We will not occupy space by a
general description of the pneumatic system, one great feature in
which is the continuous manufacture of malt throughout the year
instead of only from five to eight months of the year, as it will
be gathered from the following description of the Troyes
malting:

FIG. 5.–ECHANGEUR, AXIAL SECTION.

In our engravings, Figs. 1, 2, and 3, the letter A indicates the
germinating cases; B, Saladin’s patent turning screws; C A, air
channels; D, passages; E R, main driving shafts; e, pulleys; F,
metal recesses to fit turning screws; G, elevators; H, trap doors;
I, air channels; J, openings to growing floor for air; K S, engines
and fan room; L N, fans, supply and exhaust; T, boiler; U, chimney;
f, well. The capacity of the malting is 130 qr. malt every day.
This is equivalent to an English house of 520 qr. steep. The whole
space occupied is the area necessary for kilns, malt and barley
stores, engine and boiler house, and fans. No additional area is
required for germinating floors, as ten germinating cases, A, are
placed in the basement below the kilns and stores. The building is
of brick, with the internal walls below the ground line resting
upon cast iron columns and rolled joists. The germinating cases, A
A, are of iron; the bottoms are double. One of perforated plate is
placed 6 inches above the bottom. These plates admit of draining
the corn if the germinating case is used as a steeping cistern
also. Their chief object is, however to admit of ready circulation
of the air by the means presently to be described. Large channels,
A a, serve as drains for moisture and to convey the air to or from
the growing corn. Between each case is a passage, D, enabling the
maltster to have free access to the corn at all points.

FIG. 6.–ECHANGEUR TRANSVERSE SECTION.

With the exception of the driving shaft, E, all the machinery is
in duplicate, so that the possibility is remote of any breakdown
that would seriously affect the working of the house. This is
necessary, as should the fans, L N, be stopped for twenty-four
hours the corn germinating at a depth exceeding 30 inches would
heat and impair its vitality. The boilers, T, and engines, S, are
of the common type of 20 horse power nominal. The fans, L N, are
the Farcot patent, illustrated a short time since in our pages. The
lower floors of the kilns are provided with the Schlemmer patent
mechanical turners. The turners, Fig. 4, in the germinating cases
are Saladin’s patent.

FIG. 7.–ECHANGEUR, SECTIONAL PLAN.

The germination of the grain is effected by means of cool moist
air provided by the fan described and the cooler and
moistener–Figs. 5, 6, and 7, herewith–known as an
echangeur. As the germinating grain has a depth of from 30
inches to 40 inches some pressure is required, and mechanical means
are necessary for efficient and economical turning. The
echangeur is a very ingenious application of the well
understood rapidity of evaporation of any liquid when spread out in
very thin layers over large surfaces and exposed to a current of
air. It consists of a cylinder, or series of cylinders, of
increasing diameter, placed one within another. Each consists of
finely perforated sheet iron. They are placed in a trough of water,
just sufficiently immersed to insure complete wetting. When rotated
at a slow speed, the surfaces of all the cylinders are kept just
wetted. A volume of air is either driven or drawn through, as may
be required for any particular purpose. In the model malting, as
shown at Fig. 4, taken from that shown at the Brewery Exhibition,
the air was driven through the echangeur and thence through
the germinating barley. Here or as employed in the malting
illustrated, the air in its passage comes first into contact with
the moistened cylinders, and if hot and dry it becomes moist and
cool, for the constant evaporation upon the cylinders has a very
considerable refrigerating effect.

This was well known to the Egyptians over four thousand years
ago, and the porous bottle–gergeleh–of Esnch has been made
until the present day, to keep the drinking water cool and fresh.
The echangeur is like a gigantic gergeleh, and by increasing
the size and number of the cylinders, and causing the water in the
moistening trough to circulate, any volume of air can be wetted to
the saturation limit corresponding to its temperature. It will be
seen that this apparatus gives the maltster complete control of the
humidity and heat as well as volume of the air driven through
germinating corn.

Fig. 8.

The turning apparatus is shown by Fig. 4, and consists, as will
be seen, of a cylindrical frame provided with rollers which run on
rails at the edge of the germinating cases. It is carried to and
fro from either end of the case by compensating rope gearing which
at the same time gives motion to the gearing actuating the turning
screws. These screws do not quite touch the bottom of the
germinating case, but are provided with a pair of small brushes, as
shown in the annexed engraving, Fig. 8, which just skim it. The
apparatus shown has but three of these screws, but the cases are
generally made wide enough for six. The kilns are double, each
possessing two floors, and worked upon the Stopes’ system. The
construction of the furnaces is of the ordinary French pattern. The
arrangement of the house permits of great regularity in working.
Every day 130 qrs. of barley is screened, sorted, cleaned, and
passed into a steeping cistern. When sufficiently steeped it runs
through piping into the germinating case, which, in the natural
order of working, is empty. Here it forms the couch. When it is
desirable to open couch a small amount of air is forced through the
grain by opening the trap door connected with the main air channel.
This furnishes the growing corn with oxygen, removes the carbonic
acid gas, and regulates temperatures of the mass of grain. Later
the Saladin turner is put in motion about every eight to twelve
hours. The screws in rotating upon their axes are slowly propelled
horizontally. They thus effectually turn the grain and leave it
perfectly smooth. This turning prevents matting of the roots, the
regulation of temperature and exposure to air being effected by
means of the cold air from the echangeur. When the grain is
sufficiently grown it is elevated to the kilns. For forty hours it
remains upon the top floor. It is then dropped upon the bottom
floor, a further charge of green corn following upon the top floor.
The benefit is mutual. The bottom floor is maintained at an even
temperature, being virtually plunged in an air bath; free radiation
of heat is prevented; the top surface of the malt is necessarily
nearly as warm as that next the wires, which in its turn is subject
to lower heats than would be necessary if free radiation from the
surface was allowed. The top floor is by the intervention of the
layer of malt between it and the fire prevented it from coming into
direct contact with heat of a dangerous and damaging degree. The
same heat which is used to dry one floor, and in an ordinary kiln
passes at once into the air as waste, is the best possible
description of heat, namely, very slightly moistened heated air, to
remove the moisture from the second layer of malt at a low
temperature. It is of vital importance to retain this green malt at
a low heat so long as any percentage of moisture exceeding, say, 15
per cent, is retained by the corn.

The regulation of temperature is shown by the diagrams, Figs. 9
and 10:

Fig. 9.

Fig. 10.

The distribution of the heated air in the kiln is rarely as
uniform as is supposed, the temperature of the malt on drying floor
being very different at different parts. In illustration of this,
the following may be taken from a statement by Mr. Stopes of the
results of an examination of the temperatures at different parts of
a drying floor in a kiln in Norfolk: “A malting steeping 105 qr.
every four days has a kiln 75 feet by 36 feet; an average drying
area of under 26 feet per qr. The consequent depth of green malt
when loaded is over 10 inches. The total area of air inlets is less
than 27 feet super. The air outlet exceeds 117 feet, a ratio of 13
to 3. The capacity of head room equals 44,550 feet cube. The area
of each tile is 144 inches, with 546 holes, giving an effective air
area of some 32 inches. The ratio of non-effective metallic surface
to air space is thus 9 to 2.” The Casella anemometer gave no
indications at several points, and fluctuating up and down draughts
were observable at many others, especially at two corners and along
the center. “The strongest upward draught pulsated with the gusts
of wind and ranged from 30 feet to 54 feet per minute, a down
draught of equal intensity occurring at intervals at the same spot,
notwithstanding the fact that the air was rushing in at the inlets
below the floor at the high velocity of 785 feet per minute. The
temperatures of the drying malt and superimposed air consequent
upon the conditions thus indicated were naturally as follows: At B,
the place supposed to be hottest: Heat of malt touching tiles, 216
deg.; heat of malt 1 inch above tiles, 167 deg.; heat of malt 3
inches above tiles 154 deg.; heat of malt 4 inches above tiles, 152
deg.; heat of malt 5 inches above tiles, 142 deg.; heat of malt on
surface, 112 deg. At A, the place supposed to be coldest: Heat of
malt next tiles, 174 deg.; heat of malt 2 inches above tiles, 143
deg.; heat of malt 4 inches above tiles, 135 deg.; heat of malt on
surface, 104 deg.; the heat of the air 3 feet above tiles, 84 deg.;
the heat of the air 5 feet above tiles, 82 deg. Fig. 9 shows the
temperature at twenty-six points close to the tiles, taken with
twelve registered and accurate thermometers in the space of fifteen
minutes.” These and other similar tests have led to the conclusion
that the best malt drying cannot be done on a single floor.

Fig. 10 is a similar diagram showing the temperatures on a
drying floor of kiln at Poole, Dorset, altered to Stopes’ system of
drying. The temperature at different depths of the drying grain was
as follows: Malt at surface of tiles, 142 deg.; malt at 1 inch
above tiles, 142 deg.; malt at 2 inches above tiles, 142 deg.; malt
at 4 inches above tiles, 141 deg.; malt on surface, 140 deg.

The advantages of the Saladin system over that hitherto working
in Britain are numerous, and are thus enumerated by Messrs. Stopes
& Co. who are agents for M. Saladin: The area occupied by the
building does not equal one-third of that otherwise required. The
actual growing-floor space is only about one-seventh, and the
number of workmen is ruled necessarily by the size of the house,
but on an average is reduced two-thirds; but the employment of much
more power is necessary, and the power is used at more frequent
intervals. The use of plant and premises is continuous, the
processes of malting being equally well performed during the summer
months. The further advantage of this is that brewers secure entire
uniformity in age of malt. By the English system the stocks of
finished malt necessarily fluctuate largely. All grain is subjected
to the same conditions of surrounding air, exposure, and
temperature. The volume of air supplied to the germinating corn is
entirely under control, as are also its temperature and humidity.
When germination is arrested and the green malt is drying, the
double kilns insure control of the temperatures of the corn in the
kilns. The infrequency of turning the germinating grain benefits
the growth of the roots and the development of the plumule, besides
saving much labor. No grains are crushed or damaged by the feet or
shovels of workmen. The air supplied to the corn can be
inexpensively freed from disease germs and impurities. The capital
needed for malting can be reduced by the diminished cost of
installation, and the reduced stocks of malt on hand. The quality
of the malt made is considerably improved. The percentages of
acidity are much reduced. The stability of the beer is increased,
and a greater percentage of the extractive matter of the barley is
obtainable by the brewer.–The Engineer.

NON-SPARKING KEY.

Profs. Ayrton and Perry lately described and exhibited before
the Physical Society their new ammeters and voltmeters, also a
non-sparking key. The well known ammeters and voltmeters of the
authors used for electric light work are now constructed so as to
dispense with a constant, and give the readings in amperes and
volts without calculation. This is effected by constructing the
instruments so that there is a falling off in the controlling
magnetic field, and a considerable increase in the deflecting
magnetic field. The deflections are thus made proportional to the
current or E.M.F. measured. The ingenious device of a core or soft
iron pole-piece, adjustable between the poles of the horseshoe
magnet, is used for this purpose. By means of an ammeter and
voltmeter used conjointly, the resistance of part of the circuit,
say a lamp or heated wire, can be got by Ohm’s law. Profs. Ayrton
and Perry’s non-sparking key is designed to prevent sparking with
large currents. It acts by introducing a series of resistance coils
determined experimentally one after the other in circuit, thereby
cutting off the spark.

NEW INSTRUMENTS FOR MEASURING ELECTRIC CURRENTS AND
ELECTRO-MOTIVE FORCE.

By Messrs. R. E. CROMPTON and GISBERT KAPP.

[Footnote: Paper read before the Society of Telegraph Engineers,
14th February, 1884.]

In consequence of the rapid development of that part of
electrical science which may be termed “heavy electrical
engineering,” reliable measuring instruments specially suitable for
the large currents employed in lighting and transmission of energy
have become an absolute necessity. As usual, demand has stimulated
supply, and many ingenious and useful instruments have been
invented, the manufacture of which forms at the present day an
important industry. Mr. Shoolbred, in a paper which he recently
read before this Society, gave a full and interesting account of
the labors of our predecessors in this field. To-day we add to the
list then given a class of instruments invented by us, examples of
which are now before you on the table. We have preferred to call
them current and potential indicators in preference to meters,
considering that the latter term, or rather termination, ought to
be applied rather to integrating instruments, which the necessities
of electric lighting, we believe, will soon bring into extensive
use. The principal aim in the design of these indicators has been
to obtain instruments which will not alter their calibration in
consequence of external disturbing forces. If this object can be
attained, then it will be possible to divide the scale of each
instrument directly into amperes or volts, as the cause may be, and
thus avoid the use of a coefficient of calibration by which the
deflection has to be multiplied. This is an important consideration
when it is remembered that in many cases these instruments have to
be used by unskilled workmen, to whom a multiplication involving
the use of demical fractions is a tedious and in some cases even an
impossible task.

FIG. 1. FIG. 2.

All measurements are comparative. We measure weights or forces
by comparison with some generally known and accepted unit standard
weights, lengths, areas, and volumes, by comparison with a unit
length, resistance by a standard ohm, and so forth. In the same way
currents could be measured by comparison with a standard current:
but this would be a troublesome process, not only on account of the
apparatus necessary, but also because it would be a matter of some
difficulty to have a standard current always ready for use. In
general, measurement by direct comparison with a standard unit is
discarded for the more indirect method of measuring not the current
itself, but its chemical, mechanical, or magnetic effect. The
chemical method is very accurate if a proper density of current
through the surface of the electrodes be used,[1] but since it
requires a considerable time, and, above all, an absolutely
constant current, its use is almost entirely restricted to
laboratory work and to the calibration of other instruments. For
practical ready use, instruments employing the mechanical or
magnetic effect of the current are alone suitable. We weigh, so to
speak, the current against the force of a magnet, of a spring, or
of gravity. The measurement will be exact if the thing against
which we weigh or counterbalance the current itself retains its
original standard value. Where permanent magnets or springs are
used as a balancing force, this condition of constancy in our
weights and measures is not always fully maintained, and to make
matters worse, there is no visible sign by which a change, should
it have occurred, can be readily detected. A spring may have been
overstrained or a steel magnet may have become weakened without
showing the least alteration in outward appearance. To overcome
this difficulty, the obvious remedy is not to use springs or steel
magnets at all, but to substitute for these some other force which
should be either absolutely constant, such as the force of gravity,
or at least should, vary only within narrow limits, and this in
accordance with a definite law. This latter condition can be
fulfilled by the employment of electro-magnets.

[Footnote 1: According to recent experiments made by Dr.
Hammerl, the density of current in a copper voltameter should be
half an ampere per square inch of surface.]

FIG 3.

To imitate with an electro magnet as nearly as possible a
permanent magnet, so that the former can be used to replace the
latter, it is necessary that the magnetism in the iron core should
remain constant. This could, of course, be done by exciting the
electro magnet with a constant current from a separate source. (In
a recent note to the Paris Academy of Science, M.E. Ducretet
described a galvanometer with steel magnet, which is surrounded by
an exciting coil. When recalibration appears necessary, a known
standard current from large Daniell cells is sent through this coil
during a certain time, and thus the magnet is brought back to its
original degree of saturation. M. Ducretet also mentions the use of
a soft iron bar instead of a steel magnet, in which case the
current from the Daniell cells must be kept on during the time an
observation is taken.) But such a system would appear to be too
complicated for ready use. Moreover, some sort of indicator would
be required by which we could make sure that the exciting current
has the normal strength.

FIG 4.

The plan we adopt is to excite the electro magnet by the whole
or a part of the current which is to be measured. Since this
current varies, the power exciting the core of the electro magnet
must also vary; and since we require the core to have as nearly as
possible a permanent magnetic force, we are brought face to face
with the question, whether an electro magnet can be constructed
that has a constant moment under varying exciting currents. This
question has been answered by the well known experiments of Jacobi,
Dub, Mueller, Weber, and others. To get an absolutely constant
magnetic moment, is not possible, but between certain limits we can
get a very near approximation to constancy.

The relation between exciting power and magnetic moment is very
complicated, depending not only on the dimensions and shape of the
core and the manner of winding, but also on the chemical
constitution of the iron of the core. It is not possible, or at
least it has hitherto not been found possible, to embody all these
various elements into an exact mathematical formula, which would
give the magnetic moment as a function of the exciting current; but
the above mentioned experiments have shown that within certain
limits, and in the neighborhood of the point of saturation, the
relation between the two is that of an arc to its geometrical
tangent. It will be seen that for large angles the arc increases
much slower than the tangent; that is, for strongly excited cores,
a very large increase of the exciting current will produce only a
slight increase of magnetic moment. If Mueller’s formula were
correct for all currents, absolute saturation could only be reached
with an infinite current. Whether this be the case or not, it is
certain that the greater the exciting current the less will a
variation in it affect the magnetic moment of the core. To imitate
as nearly as possible permanent steel magnets, it is therefore
necessary to use electro magnets, the cores of which are easily
saturated. The core should be thin and long and of the horseshoe
type; the amount of wire wound round it should be large in
comparison with the size of the core.

Here is a magnet partly wound which was used in one of our
earliest experiments, but which was a failure on account of having
far too much mass in the core in comparison with the amount of
copper wire wound round it. Since then we have greatly diminished
the iron and increased the copper. The cores of the instruments on
the table are composed of two or three No. 18 b.w.g. charcoal iron
wires, and are wound with one layer of 0’120 inch wire in the case
of the current indicators, and eighteen layers of 0.0139 inch wire
in the case of the potential indicator. If from the diagram, Fig.
1, we plot a curve the abscissae of which represent exciting
current, and the ordinates magnetic moment of the soft iron core,
we find that a considerable portion of the curve is almost a
straight and only slightly inclined line. If it, were a horizontal
straight line the core would be absolutely saturated, but such as
it is, it answers the purpose sufficiently well, for with a
variation of exciting current from 10 to 100 amperes the magnetic
moment varies but slightly. If a small soft iron or magnetic steel
needle, n s, be suspended between the poles, S N, of an
electro magnet of such proportions as described above, and the
current, after exciting the electro magnet, e e, be lead
round the coils, DD, it will be found that for all currents between
10 and 100 amperes the needle, n s, shows a definite
deflection for each current. Here we have a galvanometer with
permanent calibration. In this case the deflection of the needle
will not strictly follow the law of tangents, because the directing
power of the electro magnet is not absolutely constant; but
whatever the exact ratio between deflection and current may be, it
must always remain the same, and to each angle of deflection
corresponds one definite strength of current.

The force with which the electro magnet tends to keep the needle
in its zero position, that is, in line with the poles, S N, is due
partly to the magnetism of the core, which is nearly constant, and
partly to the magnetic influence of the coils, ee,
themselves, which is, of course, simply proportional to the
current. The total magnetic force acting on the needle is,
therefore, represented by the sum of these two forces, and
consequently not nearly so constant as might be desired in order to
get a good imitation of a tangent galvanometer with a permanent
magnet. In the diagram, Fig. 2, the curve, O A B, represents the
magnetic moment of the iron core, the straight line, ODE, that of
the exciting coils per se, and the dotted line, O F M, the sum of
the two, obtained by adding for every current, O C, the respective
ordinates, CD and C A.

The rise of this curve shows that the force which tends to bring
the needle back to its zero position increases with the current,
though at a slower ratio than the deflecting force of the current.
It follows from this that for large currents the increment in the
angle of deflection is comparatively small, and the divisions on
the scale whereon the current is to be read off would come too near
together to allow accurate readings to be taken. In other words,
the range of accurate reading in an instrument so constructed would
only be limited. But it is very easy to eliminate the magnetic
effect of the coils of the electro magnet on the needle, by
introducing an opposite magnetic effect, so that only that part of
the force remains which belongs to the soft iron core proper. One
way of doing this is by surrounding the needle with a coil, the
plane of which is at right angles to the line, S N, and coupling
this coil in series with the deflecting coil, D D. If the
proportions of this transverse coil and the direction of the
current through it be properly chosen, its magnetic effect can be
made to exactly counterbalance that of the exciting coils, e
e, without perceptibly weakening the magnetism of the iron
core. But instead of employing two coils, one parallel and the
other transversely to the zero position of the needle, we can
obtain the same result in a more simple manner with one coil only,
if this be placed at such an angle that its magnetic effect can be
substituted for the combined effects of the two coils. In other
words, we set the deflecting coil, D D, at a certain angle to the
zero position of the needle.

A similar arrangement, though not precisely for the same
purpose, has already been suggested and tried by Messrs. Deprez,
Carpentier, Ayrton, and Perry, in galvanometers with permanent
steel magnets. If the coil, D D, be so placed, the deflecting force
which now acts obliquely can be considered as the resultant of two
forces, one acting at right angles to the line, S N, as in an
ordinary galvanometer, and the other parallel to this line, but in
a sense opposed to the action of the electro magnet and its
exciting coils. If the angle of obliquity be so chosen that this
latter component exactly equals the magnetic effect of the exciting
coils per se, an equality which holds good for all currents,
then we shall have an almost perfect imitation of a tangent
galvanometer with permanent magnets. But we can go a step further
than this; we can overbalance the exciting coils by setting the
deflecting coil at a greater angle than necessary for the mere
elimination of the former, and thus attain that an increase of
current results in a slight weakening of the field in which the
needle swings, thus allowing the increment of the angle of
deflection to be comparatively large even for large currents. In
this way it is possible to obtain a more evenly divided scale than
in the case when the deflection follows the law of tangents, as in
an ordinary tangent galvanometer. This principle of overbalancing
the exciting coils is shown on diagram, Fig. 2. The straight line,
O G, represents the magnetic effect on the needle of that component
of the deflecting force which is parallel, but in sense opposed to
S N; as mentioned above, the magnetic effect of the exciting coils
is represented by the straight line, O E. The combined effect of
these two forces on the needle is represented by the line, O K, the
ordinates of which must be deducted from those of the curve, O A B,
in order to obtain the total directing force due to each current.
This is shown by the curve, O P Q, shown in a thick full line. This
curve shows how the directing force or strength of field in which
the needle swings decreases with an increasing current. That this
does actually take place can easily be proved by experiment.

Fig. 4 shows two curves; the one drawn in a full line is
obtained by plotting the deflection in degrees of the needle of a
potential indicator as abscissae, and the corresponding
electromotive forces measured simultaneously on a standard
instrument as ordinates; the dotted line shows what this curve
would be with an ordinary tangent galvanometer.

The needle of the potential indicator is mounted at the lower
end of a steel axle, to the upper end of which is fastened a light
aluminum pointer, whereby the deflection of the needle can be read
off on a scale divided directly into volts. The scale is placed
within a circular dial plate with glass cover, giving sufficient
room for the pointer to swing all round, and the needle is placed
within a central tube fitting it closely, which acts as a damper
and so makes the instrument almost dead beat. Tube and dial are in
one casting. The electro magnet is of horseshoe form fastened to a
central tubular stand, which also serves to support the two
deflecting coils, one on either side of it. The tube within which
the magnetic needle swings is inserted into the stand, which is
bored out to the external diameter of the tube. The electro magnet
and deflecting coils are wound with from 50 to 100 ohms of fine
insulated copper wire, and an additional resistance coil of from
450 to 900 ohms of German silver is added, which can, however, be
short circuited by depressing a key when the instrument has to be
used for reading low electromotive forces. In this case the
indication of the pointer must be divided by ten. If a current be
sent through the instrument the wrong way, the needle turns through
an angle of 180°, and thus brings the pointer to the side of
the dial opposite to where the scale is. In this position no
reading can be taken, and to facilitate the sending of the current
in the right direction a commutator is added, and the same is so
coupled up that when the pointer stands over the scale the handle
on the commutator points to the positive terminal screw. There is a
limit of electromotive force below which the indicator fails to
give reliable readings. For instance, an instrument wound with 100
ohms of copper wire and 900 ohms of German silver can be used for
electromotive forces varying between 300 and 3 volts, but would not
be reliable for measuring less than 3 volts.

For very exact measurements the instrument should be placed
north and south, in the same position in which it was calibrated.
Two different patterns of current indicators are on the table; one
with double needles suspended on a point in the way compass magnets
are suspended, the other with one lozenge shaped needle mounted on
an axle and pivoted on jewels, in every way similar to the needle
of the potential indicator first described.

For measurements of currents from 10 amperes upward, there is no
need to employ a complete coil as the deflecting agent; one
half-coil or one strip passing close under the needle gives
sufficient deflecting force, and thus the construction of the
instrument is rendered extremely simple. The current, after
entering at one of the flat electrodes, splits in two parts, each
part passing round the winding of an electro magnet of horseshoe
form, the similar poles of both magnets pointing toward each other
and toward the needle. After traversing the winding, the current
unites again, and passes through a metal strip close under the
needle, and finally out of the instrument by the other electrode,
which lies close under that at which the current entered, but is
insulated from it by a sheet of fiber. The metal strip is set at an
angle, to balance or overbalance, as may be preferred, the magnetic
influence of the exciting coils. The effect of this overbalancing
is shown in Fig. 5, where the full curve represents the current as
a function of the deflection–obtained by comparison with a
standard instrument–and the dotted curve shows what that relation
between deflection and current would be if the law of tangents held
good for these instruments. It will be seen that, about the middle
of the scale, the dotted line coincides nearly with the full line,
while at the extreme end of the scale the dotted line is higher.
From this follows, that if we compare our indicator from which this
curve was taken with any form of tangent instrument showing an
equal angle of deflection at the medium reading, it will be seen
that the needle of our indicator will be deflected to a greater
angle at high readings than that of the tangent galvanometer.
Consequently, the divisions on the scale will be widest apart in
our instruments, which greatly facilitates high readings.

SECONDARY BATTERIES.

The Consolidated Electric Light Company has now completed the
secondary battery which has for some time engaged the attention of
its officers, and their regular manufacture and use for electric
lighting stations have been fairly entered upon. Among other places
to which the batteries have been sent and put into work is
Colchester, where the company has for some time had an installation
at work, chiefly employing incandescent lamps. The battery consists
of lead electrodes, anode and cathode being of the same character.
They are constructed of narrow ribbons of lead, each element being
made from long lengths of the ribbon about or nearly 0.20 in.
width, rolled together into a flat cake like rolls of narrow
webbing, as illustrated by the annexed diagram, Fig. 1, the greater
part of the ribbon being very thin and flat; but intermediate
thicker ribbons are also employed, as in Fig. 2, this thicker
ribbon being corrugated as shown, and affording passage room for
the circulation of the electrolyte. From four to eight coils of the
plain ribbons are between every pair of corrugated ribbons. They
are wound up together tightly, and pressed into the nearly
rectangular form shown. The bar for suspending the coil plates so
made in the cells is soldered to the coil. The object of this
construction is of course to obtain large lead surface, and of
course a much larger surface is so obtained than could be
practically obtained from plain lead plates in the same compass. A
battery thus made may be seen at the offices of the company, 110
Cannon Street.

FIG. 1. FIG. 2.

A very ingenious device for cutting the battery out of circuit
when charged as much as is thought desirable is used by the
company. In a cell is an element which has a determined lower
capacity than those in the rest of the battery. Over this element
is placed a gas-tight chamber in which is a diaphgram, this
diaphragm being of very flexible material placed in the cover of
the box of cells. When charging has proceeded as long as is
desirable, or proceeds too fast, hydrogen is evolved, and this
collecting in the chamber referred to acts upon the diaphragm, and
by means of a rod connected thereto, switches the current, which is
supplied to an electro-magnet and by which circuit is made through
the medium of mercury contacts. The object, of this is to save the
battery from destruction by over-charging or charging by too large
a current.–The Engineer.

ACETYLENE FROM IODOFORM.

P. CAZENEUVE publishes in the Comptes Rendus a new method
for the preparation of acetylene, which consists in mixing iodoform
intimately with moist and finely divided silver. An abundant
evolution of acetylene takes place without heating. The reaction is
represented by the following formula: 2CHI₃ + 6Ag =
C₂H₂ + 6 AgI. The decomposition of the
iodoform is hastened if the silver is mixed with finely divided
copper, such as can be obtained by precipitating it from its
sulphate by means of zinc.

Cazeneuve also observed that most metals which have any affinity
for iodine will decompose iodoform in the presence of water,
forming acetylene and an iodide of the metal. By the use of zinc he
obtained a liquid having a pleasant ethereal odor, and a gas
mixture that contained besides acetylene an iodine compound which
burned with a purple-edged, fawn-colored flame.

WHEN DOES AN ELECTRICAL SHOCK BECOME FATAL?

In this age of electricity and electric wires carrying currents
of various intensity, the question of danger arising from contact
with them has caused considerable discussion. An examination into
the facts as they exist may therefore enlighten some who are at
present in the dark.

To begin with, we often hear the question asked–why is it that
certain wires carrying very large currents give very little shock,
whereas others, with very small currents, may prove fatal to those
coming in contact with them? The answer to this is–that the shock
a person experiences does not depend upon the current flowing in
the wires, but upon the current diverted from them and
flowing through the body.

The muscular contraction due to a galvanic current, which was
first observed in the frog, gives a good illustration of the fact
that it requires only a very minute current to flow through the
muscles in order to contract them. Thus the simple contact of
pieces of zinc and copper with the nerves generated current
sufficient to excite the muscles–a current which would require a
delicate galvanometer for its detection. What is true of the
muscles of the frog holds good also for the human muscles; they too
are very susceptible to the passage of a current.

In order to determine the current which proves fatal we need
only to apply the formula which expresses Ohm’s law, viz., C=E/R,
or the current (ampere) equals the electromotive force (volt)
divided by the resistance (ohm).

According to the committee of Parliament investigation, the
electromotive force dangerous to life is about 300 volts; this then
is the quantity, E, in the formula. There remains now only to
determine the resistance in ohms which the body offers to the
passage of the current. In order to obtain this, a series of
measurements under different conditions were made. On account of
the nature of the experiment a high resistance Thomson reflecting
galvanometer was used, with the following results.

When the hands had been wiped perfectly dry, the resistance of
the body was about 30,000 ohms; with the hands perspiring
ordinarily it fell to 10,000 ohms; whereas when they were dripping
wet it was as low as 7,000 ohms. Our readers can judge this
resistance best when we state that the Atlantic cable offers a
resistance of 8,000 ohms.

Taking an ordinary condition of the body, with the hands
perspiring as usual, we would have the resistance equal to 10,000
ohms. Applying the two known quantities in the formula, we get:

This means, therefore, that when the electromotive force or
potential is great enough to send a current of 1/33 ampere through
the body, fatal results will ensue. This current is so minute that
it would deposit only about 6 grains of copper in one
hour, a grain being 1/7,000 of a pound.

Let us now compare these figures with some actual cases, taking
as an example a system of incandescent lighting. In these systems
the difference of potential between any two points of the circuit
outside of the lamps does not exceed 150 volts. Taking this figure,
therefore, it will be seen that under no circumstances can the
shock received from touching these wires become dangerous–not even
by touching the terminals of the dynamo itself; because in neither
case can a current be driven through the body, sufficient to cause
an excessive contraction of the muscles.

In a system of arc lighting, however, we have to deal with
entirely different conditions; for, while in the incandescent
system the adding of a lamp, which diminishes the resistance,
requires no increase of electromotive force, the contrary is the
case in the arc light system. Here every additional lamp added to
the circuit means an increase in resistance, and consequent
increase in electromotive force or potential. Taking for example a
well known system of arc lighting, we find that the lamps require
individually an electromotive force of 40 volts with a current of
10 amperes. In other words, the difference in potential at the two
terminals of every such lamp is 40 volts. Consequently, if the
circuit were touched in two places, including between them only one
lamp, no injurious effects would ensue. If we touch the circuit so
as to include two lamps between us, the effect would be greater,
since the potential between those two points is 2 x 40 volts. We
might continue in this manner touching the circuit until we had
included about 7 or 8 lamps, when the shock would become fatal,
since the point would be reached at which the difference of
potential is great enough to send a dangerous current through the
body.

Up to this point we have assumed that, while touching two points
in the wire, the rest of the circuit is perfectly insulated, so
that no current can leak, in other words, that the circuit is
nowhere “grounded.” If this is not the case we may, under suitable
conditions, receive a shock by touching only one point of
the wire. This becomes clear by considering the current to leak
from another spot of different potential, to pass through the
ground and into the body; thus, on touching the wire the body
virtually makes a connection between the two points of the circuit.
In clear dry weather such leaks are insignificant; but in damp and
rainy weather, and with poor insulation, they may rise to such a
point at which it would be dangerous to touch the circuit even with
one hand, the leaks being sometimes so great as to cause the lamps
to burn in a fitful, desultory manner, and to go out entirely.

There is still another factor which enters into the discussion
of the danger of electric light wires. This must be looked for in
the fact that the physiological effects are greatest at the moment
of the opening or the closing of the circuit; or in a closed
circuit they are the more marked when the flow of current stops and
starts, or diminishes and increases. In dynamo electric machines
the current is not absolutely continuous or uniform, since the
coils on the armature being separated a distance cause a slight
break or diminution of the current between each. This break is so
short that it does not interfere with the practical work for
lighting; in some constructions, nevertheless, the distances apart
is so great that, while not interfering with light, its effects
upon the muscles are greatly increased over those of other
constructions which give a more uniform current.

All these statements might lead to the conclusion that arc light
wires are dangerous under any circumstances; but this is not the
case. The first and only requisite is, that they be perfectly
insulated. When thus protected accidents from them are impossible,
and all mishaps that have occurred through them can be traced
directly to the lack of insulation. Nevertheless, we would warn our
readers against experimenting upon arc wires by actual trial,
because unforeseen conditions might lead to disagreeable
results.

ROBERT CAUER’S STATUE OF LORELEI.

The statue of Lorelei, the mythical siren of the Rhine,
represented in the annexed cut, which is taken from the
Illustrirte Zeitung, was modeled by Robert Cauer, of
Kreuglach on the Rhine. He was born at Dresden in 1831, and is the
son of the well-known sculptor Emil Cauer, and a brother of the
sculptor Karl Cauer.

LORELEI STATUE BY ROBERT CAUER.

REDUCING AND ENLARGING PLASTER CASTS.

Ordinary casts taken in plaster vary somewhat, owing to the
shrinkage of the plaster; but it has hitherto not been possible to
regulate this so as to produce any desired change and yet preserve
the proportions. Hoeger, of Gmuend, has, however, recently devised
an ingenious method for making copies in any material, either
reduced or enlarged, without distortion.

The original is first surrounded with a case or frame of sheet
metal or other suitable material, and a negative cast is taken with
some elastic material, if there are undercuts; the inventor uses
agar-agar. The usual negative or mould having been obtained as
usual, he prepares a gelatine mass resembling the hektograph mass,
by soaking the gelatine first, then melting it and adding enough of
any inorganic powdered substance to give it some stability. This is
poured into the mould, which is previously moistened with glycerine
to prevent adhesion. When cold, the gelatine cast is taken from the
mould, and is, of course, the same size as the original. If the
copy is to be reduced, this gelatine cast is put in strong alcohol
and left entirely covered with it. It then begins to shrink and
contract with the greatest uniformity. When the desired reduction
has taken place, the cast is removed from its bath. From this
reduced copy a cast is taken as usual. As there is a limit to the
shrinkage of the gelatine cast, when a considerable reduction is
desired the operation is repeated by making a plaster mould from
the reduced copy, and from this a second gelatine cast is taken and
likewise immersed in alcohol and shrunk. It is claimed that even
when repeated there is no sacrifice of the sharpness of the
original.

When the copy is to be enlarged instead of reduced, the gelatine
cast is put in a cold water bath, instead of alcohol. After it has
swollen as much as it will, the plaster mould is made as before.
For enlarging, the mould could also be made of some slightly
soluble mass, and then by filling it with water the cavity would
grow larger, but it would not give so sharp a copy.

STRIPPING THE FILM FROM GELATINE NEGATIVES.

We have frequent inquiries as to the best means of removing a
gelatino-bromide negative from its glass support so that it can be
used either as a direct or reversed negative, and it does not
appear to be very generally known that about two years ago Mr.
Plener described a method which answers well under all
circumstances, whether a substratum has been used or not.

If a negative is immersed in extremely dilute hydrofluoric acid
contained in an ebonite dish, say half a teaspoonful to half a pint
of water, the film very soon becomes loosened, and floats off the
glass, this circumstance being due to the solvent action which the
acid exercises upon the surface of the plate as soon as it has
penetrated the film. If the floating film be now caught upon a
plate which has been slightly waxed, and it is allowed to dry on
this plate, it will become quite flat and free from wrinkles. To
wax the plate, it should be held before the fire until it is
moderately hot, after which it is rubbed over with a lump of wax,
and the excess is polished off with a piece of flannel. When the
film is dry, it will leave the waxed glass immediately, if one
corner is lifted by means of a penknife. The film will become
somewhat enlarged during the above-described operation; but, by
taking suitable precautions, this enlargement may be avoided. It is
also convenient to prepare the hydrofluoric acid extemporaneously
by the action of sulphuric acid on fluoride of sodium; and, in many
cases, it is advisable to thicken up the film by an additional
layer of gelatine.

The following directions embody these points. The negative,
which must be unvarnished, is leveled, and covered with a layer of
warm gelatine solution (one in eight) about as thick as a sixpence.
This done, and the gelatine set, the plate is immersed in alcohol
for a few minutes in order to remove the greater part of the water
from the gelatinous stratum. The next step is to allow the plate to
remain for five or six minutes in a cold mixture of one part of
sulphuric acid with twelve parts of water, and in the mean time two
parts of sodium fluoride are dissolved in one hundred parts of
water, an ebonite tray being used. A volume of the dilute sulphuric
acid equal to about one-fourth of the fluoride solution is next
added from the first dish, and the plate is then transferred to the
second dish, when the film soon becomes liberated. When this is the
case, it is placed once more in the dilute sulphuric acid. After a
few seconds it is rinsed in water, and laid on a sheet of waxed
glass, complete contact being established by means of a squeegee,
and the edges are clamped down by means of strips of wood held in
position by American clips or string. All excess of sulphuric acid
may now be removed by soaking the plate in methylated alcohol,
after which it is dried. It is as well to add a few drops of
ammonia to the last quantity of alcohol used.

The plate bearing the film negative is now placed in a warm
locality, under which circumstances a few hours will suffice for
the complete drying of the pellicular negative, after which it may
be detached with the greatest ease by lifting the edges with the
point of a penknife.–Photo. News.

NEW ANALOGY BETWEEN SOLIDS, LIQUIDS, AND GASES,

By W. SPRING.

The author asks in the first place, What is the cause of the
different specific gravities of one and the same metal according as
it has been cast, rolled, drawn into wire, or hammered? Does the
difference observed prove a real condensation of the matter under
the action of pressure, or is it merely due to the expulsion by
pressure of gases which have been occluded when the ingot was cast?
According to well-known researches, metals such as platinum, gold,
silver, and copper, which have been proved to occlude gases on
fusion, and to let them escape, incompletely, on
solidification, are precisely those which are most increased in
their specific gravity by pressure. The author has submitted to
pressures of about 20,000 atmospheres metals which possess this
property, either not at all, or to a very trifling extent, and he
finds that though a first pressure produces a slight permanent
increase of density, its repetition makes little difference. Their
density is found to have reached a maximum. Hence the density of
solids, like that of liquids, is only really modified by
temperature. Pressure effects no permanent condensation of solid
bodies, except they are capable of assuming an allotropic condition
of greater density. The author’s former researches tend to show
that solid matter, in suitable conditions of temperature, takes the
state corresponding to the volume which it is compelled to occupy.
Hence there is an analogy between the allotropic states of certain
solids and the different states of aggregation of matter. Possibly
the different forms of matter may be due to a single
cause–polymerization. The limit of elasticity of a solid body is
the critical moment when the matter begins to flow under the action
of the pressure to which it is submitted, just as, e.g., ice at or
below 0° may be liquefied by strong pressure. A brittle body is
simply one which does not possess the property of flowing under the
action of pressure.

HYDROGEN AMALGAM.

Hydrogen, although a gas, is recognized by chemists as a metal,
and when combined with any solid metal–as in the case known to
electricians as the polarization of a negative element,–the
compound may correctly be termed an alloy; while any compound of
hydrogen with the fluid metal mercury may with equal correctness be
termed an amalgam of hydrogen, or “hydrogen amalgam.” The efforts
of many chemists and mining engineers have for many years been
devoted to a search for some effective and economical means for
preventing the “sickening” of mercury and its consequent “flouring”
and loss. Some sixteen or more years ago, Professor Crookes,
F.R.S., discovered and, after a series of experiments, patented the
use of an amalgam of the metal sodium for this purpose. He made the
amalgam in a concentrated form, and it was added in various
proportions to the mercury used for gold amalgamation. Water
becoming present, it will readily be understood that the sodium, in
being converted into the hydrate (KHO) of that metal, caused a
rapid evolution of hydrogen. The hydrogen thus evolved was the
excess over a certain proportion which enters into combination with
the mercury. While the mercury retained the charge of hydrogen, the
“quickness” of the fluid metal was preserved; but upon the loss of
the hydrogen the “quickness” ceased, and the mercury was acted upon
by the injurious components contained in the ore.

Since the introduction of the sodium amalgam, many attempts have
been made, more especially in America, to overcome the tendency of
mercury to “sicken” and lose its “quickness.” The greater number of
these efforts have been made by the use of electricity as the
active agent in attaining this end; but such efforts have been
generally of a crude and unscientific character. Latterly Mr.
Barker, of the Electro-amalgamator Company, Limited, has introduced
a system–already detailed in these pages–by which the mercury is
“quickened.” In his method the running water passing over the
tables, or other apparatus of a similar character, is used as the
electrolyte. In this arrangement, the mercury being the cathode,
plates or wires of copper constituting anodes are brought into
contact with the water passing over the mercury in each “riffle.”
Both the cathode and the anodes are, of course, maintained in
contact with the poles of a suitable source of electrical supply.
The current then passes from the copper anode through the running
water to the mercury cathode, and so on to the negative pole of the
electro-motor. As a consequence of this arrangement, hydrogen is
evolved from the water, and has the effect of reducing any oxide or
other detrimental compound of the metal; in other words, it
“quickens” and prevents “sickening” of the fluid metal, and
consequent “flouring” and loss. While the hydrogen is evolved at
the cathode, oxygen enters into combination with the copper
constituting the anodes. This to some extent impairs the
conductivity of the circuit.

The latest process, however, is that of Mr. Bernard C. Molloy,
M.P., which we have already characterized as highly scientific and
effective, the production of a suitable amalgam being obtained
under the most economical and simple conditions. This process has
the advantage of producing not only a hydrogen amalgam, but also at
will an amalgam of hydrogen combined with any metal
electro-positive to this latter. Thus hydrogen potassium or
hydrogen sodium can be obtained, as will be seen by the following
description.

Mr. Molloy’s effort appears to have been, in the first place,
directed to a system which could be adapted to any existing
apparatus, and in certain cases where water was scarce, to avoid
altogether the use of that, in some districts, rare commodity. For
the purpose of explanation we select an ordinary amalgamating table
fitted with mercury riffles. The surface of the table is in no way
interfered with or disturbed. The bed of the riffle, however, is
constructed of some porous material, such as leather, non-resinous
wood, or cement, which serves as the diaphragm upon which the
mercury rests, and separates the fluid metal from the electrolyte
beneath. Running the full length of the table is a thin layer of
sand, supported and pressing against the diaphragm, and lying in
this sand is the anode, formed preferably of lead. A peroxide of
that metal is formed by the action of the currents, and may be
readily reduced for use over and over again after working for from
one to three months. The peroxide of lead, as is well known, is a
conductor of electricity, and this fact constitutes an important
advantage in the working of the process. The thin layer of sand is
saturated with an electrolyte, such as dilute sulphuric acid
(H₂SO₄ + 20H₂O) to give a simple
hydrogen amalgam; (Na₂SO₄ + xH₂O)
to give a hydrogen sodium amalgam; or (K₂SO₄
+ xH₂O) to give a hydrogen potassium amalgam. Numerous
other electrolytes constituted by acids, alkalies, and salts can be
used to form an amalgam permanently maintained in a condition of
“quickness” and freed from all liability to “sicken,” whatever the
components of the ore may be. The mercury is connected with the
negative pole of the voltaic battery or other electro-motor, and
the lead made with the positive pole of the same source. When the
current passes there is formed according to the nature of the
electrolyte, a hydrogen amalgam, or an amalgam of hydrogen with a
metal electro-positive to hydrogen. The electrolyte, which, it will
be understood, is distinct and apart from the body of water passing
over the table, will last almost indefinitely, there being no
consumption of any of its constituents, excepting hydrogen and
oxygen from the water of solution. The quantity of acid or saline
material contained in the electrolyte is so very small that there
can be no difficulty in finding a supply in any district. The
question of the supply of electricity is one which in many mining
districts involves considerations of practical importance, since a
large supply would necessitate water or steam power. It has been
found that two cells having an electromotive force of about two
volts each will in this process suffice; if preferred, however, a
very small dynamo machine can be used. In connection with the
electro-motive force it is requisite to use, it may be observed
that an amalgam of sodium containing only a small quantity of this
metal would, when constituting a positive element in conjunction
with a lead negative and on an aqueous electrolyte, give an
opposing electro-motive force of less than three volts. Such an
amalgam could therefore be obtained under an electro-motive force
of about four volts. The electrical resistance in the circuit
constituted by the apparatus being very small, no electrical power
is wasted. When water constitutes the electrolyte, as in Barker’s
system, then the electro-motive force required to obtain a given
current would be very much greater than that above specified. The
conditions assured under this process appear to be all that can be
required, while the amalgams obtained are those most calculated to
preserve the “quickness” and prevent the “sickening” of the
mercury.

Mr. Molloy has designed a special form of amalgamating machine
to be used in conjunction with the above process, and with or
without the aid of water. By the employment of this machine, each
particle of the ore is slowly rolled in the quickened mercury for
from fifteen to thirty or more seconds.

When the extent of the gold and silver mining industries is
considered, and when it is borne in mind that a considerable
percentage of the precious metal present in the ore is, in the
ordinary process of extraction, lost through defective
amalgamation–due to insufficient contact with the mercury or to a
total absence of contact, as in the case of float gold–it is
obvious that the introduction of any system obviating such loss is
a matter of very great importance to those who are interested in
the above mentioned industries. We expect shortly to hear of the
practical introduction on a large scale of Mr. Molloy’s process,
and we look forward with interest to the results which may be
obtained from it.–The Engineer.

TREATMENT OF ORES BY ELECTROLYSIS.

By M. KILIANI.

The author lays down general principles for electrolytic
metallurgy. Ores must be distinguished as good and bad conductors;
the former may serve directly as anodes, and are easily oxidized by
the electro-negative radicals formed at their contact, and dissolve
readily in the electrolyte. The bad conductors have to be placed in
contact with a conducting anode, formed of an inoxidizable
substance, such as platinum, manganese peroxide, or coke. In
laboratory experiments a good conducting ore is electrolyzed by
suspension from a platinum wire in connection with the source of
electricity, and is then immersed in the bath. On an industrial
scale the ore, coarsely broken up, is placed in one of the
compartments of a trough divided by a diaphragm.

On the fragments of the ore which extend up outside of the
electrolytic bath is laid a plate of copper connected with the
positive wire. Care must be taken that this plate does not plunge
into the bath, otherwise the current would not traverse the ore at
all. The cathode is preferably formed of the same metal which is to
be obtained. The bath should not contain organic acids. In practice
the common mineral acids are employed, or their salts, selecting by
preference a salt of the metal which is to be isolated. It is
convenient to pass the current through the greatest possible number
of small decomposition troughs, taking care that the resistance in
each is not too great. With a current of one and the same intensity
we obtain in n troughs n times as much metal as in a single one. To
keep down the resistance of the circuit we employ poles of a large
surface, i.e., plenty of ore and baths which are as good conductors
as possible.

The state in which the metal is deposited at the negative pole
depends on the secondary actions undergone by the electrolyte, and
especially of the escape of gas. This is a function of the
density, of the current, i.e., the proportion of its
intensity to the surface of the cathode. If the density is too
great there is an escape of hydrogen, and the metal is deposited in
a spongy condition. If the density of the current falls below a
certain minimum, an oxide is deposited in place of metal. The
electrolytic treatment of ores often renders it possible to
separate the different metals which may be present. These are
deposited in succession, and are sharply separated if the
electromotive power is not too great.

1. Zinc.–The zinciferous compounds–calamine, blende,
and zinc ash–are all poor conductors. They are first dissolved,
and the salts obtained are electrolyzed, employing anodes of coke.
Blende should be roasted before it is dissolved. The electrolytic
bath should be as concentrated as possible to avoid sponginess of
the metal and an escape of hydrogen. In a saturated solution the
formation of hydrogen decreases as the density of the current
augments.

2. Lead.–Galena is a good conductor, and may be directly
electrolyzed. The best bath is a solution of lead nitrate. The
arborescent crystallizations extend rapidly, and must be broken
from time to time to prevent the formation of a metallic connection
between the anode and the cathode. The sulphur of the galena falls
to the bottom of the bath, and may be separated from the gangue by
solution in carbon disulphide.

3. Copper.–Native copper sulphide, though a good
conductor, cannot be directly electrolyzed en account of the
presence of iron sulphide, whence iron would be deposited along
with the copper. The copper pyrites are roasted, dissolved in
dilute sulphuric acid, and the liquid thus obtained is submitted to
electrolysis.

A PEOPLE WITHOUT CONSUMPTION, AND SOME ACCOUNT OF THEIR
COUNTRY–THE CUMBERLAND TABLELAND.

By E. M. WIGHT, M.D., Chattanooga, Tenn., Late Professor of
Diseases of the Chest and State Medicine, Medical Department
University of Tennessee; Late Member of the Tennessee State Board
of Health, and ex-President of the Tennessee State Medical
Society.

During the ten years that I have practiced medicine in the
neighborhood of the Cumberland Tablelands, I have often heard it
said that the people on the mountains never had consumption.
Occasionally a traveling newspaper correspondent from the North
found his way down through the Cumberlands, and wrote back filled
with admiration for their grandeur, their climate, their
healthfulness, and almost invariably stated that consumption was
never known upon these mountains, excepting brought there by some
person foreign to the soil, who, if he came soon enough, usually
recovered. Similar information came to me in such a variety of ways
and number of instances, that I determined some four years ago,
when the attempt to get a State Board of Health organized was first
discussed by a few medical men of our State, that I would make an
investigation of this matter. These observations have extended over
that whole time, and have been made with great care and as much
accuracy as possible, and to my own astonishment and delight, I
have become convinced that pulmonary consumption does not exist
among the people native and resident to the Tablelands of the
Cumberland Mountains.

In the performance of the work which has enabled me to arrive at
this conclusion, I have had the generous assistance of more than
twenty physicians, who have been many years in practice in the
vicinity of these mountains. Their knowledge of the diseases which
had occurred there extended over a, period of more than forty
years. Some of these physicians have reported the knowledge of the
occurrence of deaths from consumption on the Tablelands, but when
carefully inquired into they have invariably found that the person
dying was not a native of the mountains, but, a sojourner in search
of health. In answer to the question: “How many cases of pulmonary
consumption have you known to occur on Walden’s Ridge, among the
people native to the mountains?” eleven physicians say, “Not one.”
All of these have been engaged in practice there more than three
years, four of them more than ten years, one of them more than
twenty, and one of them more than forty years. All the physicians
of whom inquiries have been made are now residents, or have been,
of the valleys contiguous to Walden’s Ridge, and know the mountain
people well. Four other physicians in answer to the same question
say, that they have known from one to four cases, numbering eleven
in all, but had not ascertained whether five of them were born and
raised on the mountains or not. The names and place of death of all
these cases were given, and I have traced their history and found
that but three of them were “natives,” or had lived there more than
five years, and that one of these was 57 years of age when she
died, and had suffered from cancer for three years before her
death. The two others died within six months after returning home
from long service in the army, where both contracted their
disease.

All these investigations have been made with more particular
reference to that part of the Cumberlands known as Walden’s Ridge
than to the mountains as a whole. This ridge is of equal elevation
and of very similar character to the main Cumberland range in the
southern part of Tennessee, northwest Georgia, and northwest
Alabama, and what is true of this particular part of the great
Cumberland table is, in the main, true of the remainder.

Sequatchee Valley lies between Walden’s Ridge and what is
commonly known in that neighborhood as the Cumberland Mountains,
and separates it from the main range for a distance of about one
hundred miles, from the Tennessee River below Chattanooga to Grassy
Cove, well up toward the center line of the State. Grassy Cove is a
small basin valley, which was described to me there as a “sag in
the mountains,” just above the Sequatchee Valley proper. It is here
that the Sequatchee River rises, and flowing under the belt of
hills which unites the ridge and the main range, for two miles or
more, rises again at the head of Sequatchee Valley. Above Grassy
Cove the mountains unite and hold their union firmly on their way
north as far as our State reaches.

Topographically considered as a whole, the Cumberland range has
its southern terminus in Alabama, and its northern in Pennsylvania.
It is almost wholly composed of coal-bearing rocks, resting on
Devonian strata, which are visible in many places in the
valleys.

But a small portion of the Cumberland lies above a plane of
2,000 feet. Walden’s Ridge and Lookout Mountain vary in height from
2,000 to 2,500 feet.

North of Grassy Cove, after the ridges are united, the variation
from 2,000 feet is but little throughout the remainder of the
State, and the general character of the table changes but little.
The great and important difference is in the climate, the winters
being much more severe in these mountains in the northern part of
the State than in the southern, and the summers much more liable to
sudden changes of weather. Scott, Fentress, and Morgan counties
comprise this portion of the table, and these have not been
included in my examination, excepting as to general features.

In all our southern country, and I may say in our whole country,
there is no other large extent of elevated territory which offers
mankind a pleasant living place, a comfortable climate–none too
cold or too hot–and productive lands. We have east of the upper
waters of the great Tennessee River, in our State, and in North
Carolina and Georgia, the great Blue Ridge range of mountains,
known as the Unaka, or Smoky, Chilhowee, Great and Little Frog,
Nantahala, etc., all belonging to the same family of hills. This
chain has the same general course as the Cumberlands. It is a much
bolder range of mountains, but it is vastly less inhabitable,
productive, or convenient of access. The winters there are severely
cold, and the nights in summer are too cold and damp for health and
comfort, as I know by personal experience of two summers on
Nantahala River. But the trout fishing is beyond comparison, and
that is one inducement of great value for a stout consumptive
who is a good fellow. These mountains are much more broken
up into branches, peaks, and spurs than the Cumberlands. They
afford no table terrritory of any extent. There are some excellent
places there for hot summer visits–Ashville, Warm Springs,
Franklin, and others.

The Cumberland Mountains, as a whole, are flat, in broad level
spaces, broken only by the “divides,” or “gulfs,” as they are
called by the inhabitants, where the streams flow out into the
valleys.

Walden’s Ridge, of which we come now to speak particularly, is
the best located of any part of the Cumberlands as a place for
living. From the separation of this ridge from the main range of
Grassy Cove to its southern terminus at the Tennessee River, it
maintains a remarkably uniform character in every particular. From
it access to commerce is easy, having the Tennessee River and the
new (now building) Cincinnati Southern Railroad skirting its entire
length on the east. It rises very abruptly from both the Tennessee
and Sequatchee Valleys, being from 1,200 to 1,500 feet higher than
the valleys on each side. Looking from below, on the Tennessee
Valley side, the whole extent of the ridge appears securely walled
in at the top by a continuous perpendicular wall of sandstone, from
100 to 200 feet high; and from the Sequatchee side the appearance
is very similar, excepting that the wall is not so continuous, and
of less height.

The top of the ridge is one level stretch of plain, broken only
by the “gulfs” before mentioned and an occasional prominent
sandstone wall or bowlder. The width on top is, I should judge, 6
or 7 miles. The soil is of uniform character, light, sandy, and
less productive for the ordinary crops of the Tennessee farmer than
the soil of the lowlands. The grape, apple, and potato grow to
perfection, better than in the valleys, and are all never failing
crops; so with rye and buckwheat. Corn grows well, very well in
selected spots, and where the land is made rich by cultivation. The
grasses are rich and luxuriant, even in the wild forests, and when
cultivated, the appearance is that of the rich farms of the Ohio or
Connecticut Rivers, only here they are green and growing the
greater part of the year; so much so that sheep, and in the mild
winters the young cattle, live by the wild grasses of the forests
the whole year. The great stock raisers of the Sequatchee and
Tennessee Valleys make this the summer pasture for their cattle,
and drive them to their own farms and barns or to market in winter.
The whole Cumberland table, with the exception of that small part
which is under cultivation, is one great free, open pasture for all
the cattle of the valleys. Thousands of cattle graze there whose
owners never pay a dollar for pasturage or own an acre of the
range, though, as a rule, most of the well-to-do stock farmers in
the valleys own more or less mountain lands. These lands have,
until quite recently, been begging purchasers at from 12½ to
25 cents per acre in large tracts of 10,000 acres and upward, and
perhaps the same could be said of the present time, leaving out
choice tracts and easily accessible places, which are held at from
50 cents to $2 per acre, wooded virgin lands.

The forest growth of Walden’s Ridge is almost entirely oak and
chestnut. Hickory, perhaps, comes next in frequency, and pine
after. There is but little undergrowth, and where the forests have
never been molested there are but few small trees. This is due to
the annual fires which occur every autumn, or some time in winter,
almost without exception, and overrun the whole ridge. It does not
rage like a prairie fire. Its progress is usually slow, the
material consumed being only the dry forest leaves and grasses. The
one thing essential to its progress is these dry leaves, hence it
cannot march into the clearings. Nearly all the small shrubs are
killed by these fires, otherwise they are harmless, and are greatly
valued by the stock men for the help they render in the growth of
the wild grasses. The free circulation of air through these great
unbroken forests is certainly much facilitated by these fires,
since they destroy every year what would soon become impediments.
The destruction of this undergrowth leaves the woods open, and the
lands are mainly so level that a carriage may be driven for miles,
regardless of roads, through the forests in every direction.

The shrubs about the fields and places where the forests have
been interrupted by civilization and other causes are blackberry,
huckleberry, raspberry, sumac, and their usual neighbors, with the
azalia, laurel, and rhododendron on the slopes and in the shade of
the cliffs.

The kinds of wild grasses, I regret to say, I have not noted,
and the same of the rich and varied display of wild flowers.

The whole ridge is well supplied with clean, soft running water,
even in the driest of the season. There are no marshes, swamps, or
bogs, no still water–not even a “puddle” for long–for the soil is
of such a character, that surface water quickly filters away into
the sands and mingles with the streams in the gulfs. Springs of
mineral water are abundant everywhere. Probably there is not a
square mile of Walden’s Ridge which does not furnish chalybeate
water abundantly. Sulphur springs with Epsom salts in combination
are nearly as common.

The entire extent of Walden’s Ridge is underlaid with veins of
coal, and iron ore is plentiful, especially in the foot hills. The
coal and iron are successfully mined in many places on the eastern
slope; on the western they are nearly untouched for the want of
transportation. I find that the impression prevails that the
minerals of the Cumberlands are largely controlled by land agents
and speculators. This is only true as applied to a very small part
of the whole, not more than 1 per cent. The mineral ownership
remains with the lands almost entirely.

The prevailing winds on Walden’s Ridge are from the southwest;
northers and northeasters are of rare occurrence. One old lady who
had resided there for forty years, in answer to my query upon this
subject, said: “Nine days out of ten, the year round, I can smell
Alabama in the air.” This was the usual testimony of the residents.
Winds of great velocity never occur there. In summer there is
always an evening breeze, commencing at 4 to 6 o’clock, and
continuing until after sunrise the next morning. In times of rain,
clouds hang low over the ridge occasionally, but they never have
fogs there.

The range of the thermometer is less on the Tablelands than in
the adjacent valleys. I have had access to the carefully taken
observations of the Lookout Mountain Educational Institute, such
published accounts as have been made by Professor Safford, State
Geologist, Mr. Killebrew, the thorough and painstaking private
record of Captain John P. Long, of Chattanooga, and many more of
less length of time. From all these I deduce the fact that the
summer days are seven or eight degrees cooler on the mountains than
in the Tennessee Valley at Chattanooga, and five or six degrees
cooler than in the Sequatchee Valley, as far up as Dunlay and
Pikeville. The nights on the table are cooler than in the lower
lands by several more degrees than the days; how much I have thus
far not been able to state. The late fall months, the winter, and
early spring are not so much colder than the valleys as the summer
months, the difference between the average temperature of the
mountains and valleys being at that time four or five degrees less
than in the summer. There is no record of so hot a day ever having
occurred on the Cumberladd Mountains as to cause mercury to run so
high as 95° F., or so cold a day as to cause it to run so low
as 10° below zero.

In the average winter the ground rarely freezes to a greater
depth than 2 or 3 inches, and it remains frozen but a few days at a
time. Ice has been known to form 8 inches thick, but in ordinary
winters, 3 or 4 is the maximum. Snow falls every winter, more or
less, and sometimes remains for a week. Old people have a
remembrance of a foot of snow which lasted for a week.

Walden’s Ridge has a total population of a little more than
4,000, scattered over 600 square miles of surface. The number of
dwellings is about 800. Ninety per cent. of these are log houses;
70 per cent. of them are without glass windows; light being
furnished through the doorways, always open in the daytime, the
shuttered window openings, and the open spaces between the logs of
the walls. Less than 2 per cent. of these houses have plastered
walls or ceilings, and less than 5 per cent. have ceiled walls or
ceilings. About 20 per cent. of them are fairly well chinked with
clay between the logs, the remainder being but indifferently built
in that particular. Fully 90 per cent. of these abodes admit of
free access of air at all times of day and night, through the
floors beneath as well as the walls and roof above. It is the
custom of the people to guard against the coldest of days and
nights by hanging bed clothes against the walls, and many good
housewives have a supply of tidy drapery which they keep alone for
this purpose.

Wood, always at hand, is the only fuel in use. The whole heating
apparatus consists in one large open fireplace, built of stone,
communicating with a large chimney outside the house at one end,
and frequently scarcely as high as the one story building which
supports it. This chimney is constructed in such a manner as to be
a great ventilator of the whole room, quite sufficient, it would be
thought, if there were no other means of ventilation. It is usually
made of stone at the base, and that part above the fire is of
sticks laid upon one another, cobhouse fashion, and plastered over
inside and between with similar clay as that with which the house
walls are chinked.

Very few of these houses are more than one story high. They are
all covered with long split oak shingles–the people there call
them “boards”–rifted from the trunks of selected trees. There is
no sheathing on the roof beneath these shingles. They are nailed
down upon the flat hewn poles running across the rafters, at
convenient distances. Looking up through the many openings in the
roof in one of these house, one would think that this would be but
poor protection against rain, but they rarely leak.

Not one family in fifty is provided with a cooking stove. They
bake their bread in flat iron kettles, with iron covers, covered
with hot coals and ashes. These they call ovens. The meat is fried,
with only the exception of when accompanied by “turnip greens.”

The question, “What is the principal food of the people who live
on these mountains?” has been asked by me several hundred times.
The almost invariable answer has been, “Corn bread, bacon, and
coffee.” Occasionally biscuits and game have been mentioned in the
answers. All food is eaten hot. Coffee is usually an accompaniment
of all three meals, and is drunk without cream and often without
sugar. Some families eat beef and mutton for one or two of the
colder months in the year on rare occasions, though beef is
commonly considered “onfit to go upon,” as I was told upon several
occasions, and mutton sustains less reputation. Chickens are used
for food while they are young and tender enough to fry, on
occasions of quarterly meetings, visits of “kinfolks” or the
“preachers” and the traveling doctors. Fat young lambs are plenty
in many settlements from March to October, and can be had at fifty
cents each, but I could not learn that one was ever eaten.

A large majority of the adult population use tobacco in some
shape–the men by chewing or smoking, the women by smoking or
dipping snuff. They never have dyspepsia, nor do they ever get
flesh, after they pass out of childhood, though nearly all the
children are ruddy in appearance, and well rounded with fat.

One physical type prevails among the people in middle life, and
carries along into old age but little change; and old age is common
there. Nearly every house has its old man or old woman, or both.
Everybody, father and mother, and frequently grandfather and
grandmother, is still on hand, looking as brisk and moving about as
lively as the newer generations. After they pass their forty years,
they never seem to grow any older for the next twenty or thirty,
and the grandfathers and grandmothers can scarcely be selected, by
comparison, from their own children and grandchildren. The men are
taller than the average, and the women, relatively, taller than the
men. They are all thin featured, bright eyed, long haired, sharp
looking people, with every appearance of strength and power of
endurance.

I think the men who live on Walden’s Ridge can safely challenge
the world as walkers–aborigines and all; and unless the challenge
should be accepted by their own women folks, I feel quite sure they
would “win the boots.” They go everywhere on foot, and never seem
to tire.

Nearly all the people of the Tablelands are employed in the
pursuits of agriculture. Very few of them seem to be hard workers.
The men are all great lovers of the forest sports, much given to
the good, reliable, old fashioned long rifles. The women and
children are much employed in out door occupations, and live a
great portion of their time in the open air. The clothing of all
classes is scanty. The use of woolen fabrics for underwear has not
yet been introduced, and coarse cotton domestic is the universal
shirting, and cotton jeans, or cotton and wool mixed, constitute
the staple for outer wearing apparel. The men wear shoes throughout
the year much more commonly than boots. They never wear gloves,
mittens, scarfs, or overcoats, and they scorn umbrellas. Probably
this whole 4,000 people do not possess two dozen umbrellas or twice
as many overcoats. The women go about home with bare feet a great
part of the summer. They never wear corsets or other lacing.

I have learned by careful inquiry that very few of the people of
the Ridge have ever had the diseases of childhood. Scarlet fever I
could hear of in but two places, and I suppose that not one person
in fifty has had it. Whooping cough and measles have occurred but
rarely, and the large majority have not yet experienced the
realities of either. Very few people there have ever been
vaccinated, nor has smallpox ever prevailed. Typhoid, typhus, and
intermittent fevers are unknown. In the great rage of typhoid fever
which took place ten or twelve years ago in the Tennessee and
Sequatchee Valleys, not a single case occurred on the Mountains, as
I have been informed by physicians who were engaged in practice in
the neighborhood at the time. Diphtheria has never found a victim
there; so of croup. Nobody has nasal catarrh there, and a cough or
a cold is exceedingly rare.

I have said that these observations refer more particularly to
Walden’s Ridge than to the Cumberland Tablelands in our State as a
whole. This ridge was chosen by me for this examination, mainly for
the reason of its convenience, but partly owing to its being more
generally settled than any other equal portion of the table which
lies in Tennessee. Lookout Mountain is not as well located; it is
on the wrong side of the Tennessee River, and but a few acres of it
belong in this State. Sand Mountain is altogether out of the State,
but it is perhaps nearer like Walden’s Ridge in its physical
features than Lookout. That part of the Cumberlands west of
Sequatchee Valley is Walden’s Ridge in duplicate, excepting that it
is further west, and nearer the Middle Tennessee basin. There are
some small towns, villages of miners, and summer resorts there,
which interferes with that evenness of the distribution of
population which Walden’s Ridge has, rendering it more liable to
visitations of epidemic and contagious diseases. The tablelands
north of the center line of the State, above Grassy Cove, are very
similar to Walden’s Ridge, as far up as Kentucky, with the
exception before mentioned–that of climate–it being from one to
ten degrees colder in winter.

This whole Cumberland Table is no small country. It comprises
territory enough to make a good sized State. At present, it is
almost one great wilderness, in many particulars as unknown as the
Black Hills. It is coming into the world now, and will be well
known in a few years. The great city of Cincinnati has determined
to build a railroad through the very center of this great table in
the north part of the State, connecting with Chattanooga in the
southern part. This road is nearly bored through, and in another
year or two the Cumberland Tablelands in Tennessee will be much
heard of at home and abroad.

It seems to me this country has merits. It is located in the
latitude of mild climate; not so far south as to be scorched by the
hot summer sun, or visited by the great life destroying epidemics;
not so far north as to meet the severe and lengthened winters.

Climate, we know, is a fixture; it has a government; it has
rules; the weather may change, but climate does not; it is a
permanent out-door affair, and what is true of to-day was true
centuries ago, and will be true forever, in the measure of any
practical scope, at least. The people of the world are beginning to
know that the greatest destroyer of human life has its remedy in
climate.

Mr. Lombard, in his famous exhibit in relation to the prevalence
of consumption among the people of different occupations,
circumstances of life, and place of dwelling, gives the lowest
number of deaths from this cause to those who live in the open air.
He found the people who lived most in the open air, as would be
readily conjectured, in the mild latitudes, not in the countries of
hot sands or cold snows.

[The above article, in regard to which we have noticed frequent
allusions in many of our exchanges, all erroneously attributing it
to Dr. Wright, of Tennessee, and for which we have received
repeated requests quite recently, was read by the lamented Dr. E.M.
Wight at the 43d annual meeting of the Tennessee State Medical
Society, held at Nashville, April 4, 5, and 6, 1876. Its
distinguished and talented author will long be remembered as one of
the most active, earnest, and zealous members of the State Society.
At this meeting he also read a very admirable paper on “The
Microscopic Appearance of the Blood in Syphilis,” and prepared the
report of the Committee on State Board of Health, to which report
may be ascribed the honor of securing the necessary legislation
organizing the Board. A true, upright, honest man, an earnest,
devoted and zealous physician, universally esteemed and beloved by
all who knew him; himself the subject of tuberculosis, dying in the
prime of a brilliant manhood. He had but few equals in the glorious
profession he honored and loved so well.

From a careful reading of his paper, we find that he describes a
large area of territory, free, absolutely free, from subsoil
moisture, a climate mild and equable, a soil capable of producing
nearly everything necessary for the comfortable maintenance of
human life, surroundings that tempt, nay, compel the greatest
possible amount of open air life. His description is exceedingly
accurate of a plain, primitive, simple-minded people with but few
wants, many of the virtues and few of the vices of humanity. With
their surroundings, soil, climate, residence, and mode of living,
need we be surprised that “there is a people,” or a land “free from
consumption”?–ED.]–Southern Practitioner.

THE TREATMENT OF HABITUAL CONSTIPATION.

Dr. F.P. Atkinson thus writes in the Practitioner,
January, 1884: I suppose there is no derangement of the system we
are more frequently called upon to treat than habitual
constipation; and though all kinds of medicines are suggested for
its relief, they rarely produce more than temporary benefit–and it
is difficult to see how the result can well be otherwise, while the
root of the evil remains untouched. Now by far the more numerous
subjects of this disorder are women; and as they do not seem to
know that regularity is essential to the performance of every one
of nature’s operations, they appoint no stated times for trying to
get the bowels relieved, but trust to receiving intimation when the
rectal accumulation and distension can be borne no longer. This
method of action may and does answer fairly well for a time; but
nature gradually gets upset, the sensation of the lower bowel
becomes blunted, and at last it ceases to respond to the ordinary
stimulus. Then aperients are regularly resorted to, and although
these act fairly well for a time, they gradually have to be
increased in strength and frequency. Now, as regards the treatment,
the first thing to be accomplished is of course to get the rectum
well relieved; the next, to get the actions to take place at fixed
times; and lastly, it is necessary to get more tone imparted to the
muscular tissue of the bowels, so that the regularity of action may
be helped and also maintained. In order, then, to get the bowels
relieved in the first instance, it is well to give five grains of
both compound colocynth and compound rhubarb pill at bed-time (this
rarely requires to be repeated), then to take a tumblerful of cold
water the next morning on waking, and repeat it regularly at the
same time each day. Should the bowels remain sluggish for some
time, the same quantity of water may be taken daily before each
meal. Supposing no action takes place on rising or shortly after, a
small injection of warm water may be resorted to. After each
movement of the bowels, a small hand-ball syringeful of cold
water should be thrown into the rectum and retained. A soup
plateful of coarse oatmeal porridge (made with water and taken
according to the Scotch method, viz., by filling half the spoon
with the hot porridge and the other with cold milk) each night at
bed-time, or even every night and morning for a time, is often a
very great help. But above all things, it is necessary for the
patient to try and get relief at a certain fixed time
regularly every day. If these directions are strictly carried out
in their entirety, the evil, even if it has been of long standing,
will generally be corrected, and the patient will improve in health
and appearance. Of course where the constipation results from
exhaustion of the nervous system (such, for instance, as is brought
about by self-abuse), the special cause has to be taken into
consideration, and such treatment adopted as is suited to the
particular necessities of the case.

THE PYRAMIDS OF MEROE.

About fifty miles from the mouth of the Atbara, and, of course,
on the eastern bank of the Nile, stand the pyramids of Meroe. They
consist of three groups, and there are, in all, about eighty
pyramids. The presumption is that they represent the old sepulchers
of the kings of Meroe. Candance, Queen of the Ethiopians, mentioned
in Acts, chap. viii., v. 27, is supposed to have belonged to Meroe,
that being the name also of the capital, which is understood to
have been somewhere not far distant from the sepulchers. These
pyramids of Meroe possess one marked feature, distinguishing them
from the pyramids of Egypt proper–that is, they have an external
doorway or porch. As there is no entrance to the pyramid at these
porticoes, it is quite possible that they were temples for worship
or making offerings to the dead. By comparing them with the
pyramids of Ghizeh, it will be seen that they are also taller in
proportion to their base. Another important point in these porches
or temples is the existence of the arch; and that, too, an arch in
principle, with a keystone.–Illustrated London News.

THE PYRAMIDS OF MEROE, ON THE NILE.

THE PROLIFICNESS OF THE OYSTER.

In an article by Prof. Karl Mobius on “The Oyster and Oyster
Culture,” reproduced in the recently issued report of the U. S.
Commissioner of Fish and Fisheries, the author says:

A mature egg-bearing oyster lays about one million of eggs, so
that during the breeding season there are upon our oyster beds at
least 2,200,000,000,000 young oysters, which surely would suffice
to transform the entire extent of the sea-flats into an unbroken
oyster bed; for if such a number of young oysters should be
distributed over a surface 74 kilometers long by 22 broad, 1,351
oysters would be allotted to every square meter. But this sum of
2,200,000,000,000 young oysters is undoubtedly less than that in
reality hatched out, for not only do those full-grown oysters which
are over six years of age spawn, but they begin to propagate during
their second or third year, although it is true that the young ones
have fewer eggs than those which are fully developed. At a very
moderate estimation, the total number of three to six year old
oysters which lie upon our beds will produce three hundred billions
of eggs. This number added to that produced by the five millions of
full grown oysters would give for every square meter of surface not
merely 1,351 young oysters, but at least 1,535. In order to
determine how many eggs oysters produce, they must be examined
during their spawning season. This begins upon the
Schleswig-Holstein beds in the middle of June, and lasts until the
end of August or beginning of September. The spawning oyster does
not allow its ripe eggs to fall into the water, as do many other
mollusks, but retains them in the so-called beard, the mantle, and
gill-plates until they become little swimming animals. The eggs are
white, and cover the mantle and gill-plates as a semi-fluid,
cream-like mass. As soon as they leave the generative organs the
development of the germ begins. The entire yolk-mass of the egg
divides into cells, and these cells form a hollow, sphere-like
body, in which an intestinal canal arises by the invagination of
one side. Very soon the beginnings of the shell appear along the
right and left sides of the back of the embryo, and not long
afterward a ciliated pad, the velum, is formed along the under
side. This velum can be thrust out from between the valves of the
shell at the will of the young animal, and used by the motion of
its cilia as an organ for driving food to the mouth, or in swimming
as a rudder. During these transformations the original cream-white
color of the germ changes into pale gray, and finally into a deep
bluish-gray color. At this time they have a long oval outline, and
are from 0.15 to 0.18 of a millimeter in breadth. Over 300,000 can
find room upon a square centimeter of surface. If an oyster in
which the embryos are in this condition is opened, there will be
found upon its beard a slimy coating thickly loaded with
grayish-blue granules. These granules are the embryo oysters, if a
drop of the granular slime be placed in a dish with pure sea water,
the young animals will soon separate from the mass, and spread
swimming through the entire water. When the embryos are at this
stage their number may be estimated in the following manner: The
whole mass of embryos is carefully scraped from the beard of the
mother oyster by means of a small hair brush. The whole mass is
then weighed, and afterward a small portion of the mass. This small
portion is then diluted with water or spirits of wine, and the
embryos portioned out into a number of small glass dishes, so that
they can be placed under the microscope and counted. Thus, knowing
the weight of the small portion and the number of embryos in it by
count, we can estimate the total number of embryos from the weight
of the entire mass, which is also known. In this manner I estimated
the number of embryos in each of five full grown Schleswig-Holstein
oysters caught in August, 1869, and found that the average number
was 1,012,956.

Notwithstanding this great fecundity, but an extremely small
proportion of the young oysters produced during the course of the
summer arrive at maturity, 421 only out of 500,000,000 escaping
destruction. The immolation of a vast number of young germs is the
means by which nature secures to a few germs the certainty of
arriving at maturity. In order to render the ideas of
germ-fecundity and productiveness more easily understood, Prof.
Mobius makes the following comparison between the oyster and
man:

According to Wappaus, for every 1,000 men there are 347 births.
According to Bockh, out of every 1,000 men born 554 arrive at
maturity, that is, live to be twenty years or more of age; thus, on
an average, 347 children are produced from 554 mature men, or 626
children from 1,000 mature men. Since 1,000 full-grown oysters
produce 440,000,000 of germs, then the germ fecundity of the oyster
is to the germ fecundity of man as 440,000,000 to 6.26, or as
7,028,754 to 1. On the other hand, the number which arrive at
maturity is 579,002 times as great with mankind as with the oyster;
for of 1,000 human embryos brought into the world 554 arrive at
maturity, or of 440,000,000 newly born 243,760,000 would live to
grow up, while of 440,000,000 young oysters only 421 ever become
capable of propagating their species. The proportion is then 421 to
243,760,000, or as 1 to 579,002. I am fully persuaded that these
figures represent the number of oysters which arrive at maturity
more favorably than is really the case, since from every thousand
of full grown oysters it is certain that, on an average, more than
440,000,000 young are produced.

RED SKY.

The beautiful red sky which has been so frequent of late,
morning as well as evening, has excited much comment. The comment,
however, has consisted more of description, statement of fact,
theory, and wonder as to cause, rather than as to satisfactory
explanation.

Facts in the case which would reveal the secret of this
beautiful display of nature are not complete and numerous enough at
present to establish the cause of this phenomenon on a sure basis;
yet enough facts, it would seem, have been obtained to satisfy the
strong mind capable of bridging over a wide expanse.

Facts in an argument are like piers to a bridge-the more we have
of them, c. p., the more substantial the structure. When the facts
are legion, the structure becomes a causeway, and there is
no need of argument.

Argument is a bridge–the fewer the facts, the more the
necessity for the bridge; the less the facts, the more argument
necessary to connect the few we have, and the more skill is
required to make substantial connecting links between the few solid
piers (facts) that exist.

One of the queer things in connection with this is, the public
have looked chiefly, if not wholly, to the astronomers for an
explanation of this phenomenon, when it is not their special
province to explain matters in this department of nature.

The explanation belongs to the department of meteorology, and
not to astronomy. But the fact of having looked to the astronomers
shows how little the world knows of meteorology and how few
meteorologists there are able, ready, and willing to rise and
explain in face of the opposition of the public, who seem to think
that the explanation must necessarily belong to astronomy.
Astronomy proper deals with the position of the earth in space and
its relation to the other heavenly bodies, whether suns, fixed
stars, planets, satellites, comets, or other bodies in the vast
space about us. Meteorology deals with the atmosphere of the globe,
in all its forms. Astronomy could be studied in the early ages; its
grand facts were not wholly dependent upon the advanced condition
of the mechanic arts; it could be studied even without the aid of
telescopes, though telescopes have added much to its advancement.
Meteorology, on the contrary, depended on the advancement of the
arts and sciences; they must first be perfected ere we could know
much about this branch of science. To one unfamiliar with the
advancement and perfection of meteorology within the past ten
years, this statement may seem strange, yet it is an undisputable
fact that, prior to the establishment of the daily weather reports,
the knowledge on this subject amounted to very little, and was not
even worthy of being designated a science. Prior to the advent of
the weather map the world was in absolute ignorance of the laws
governing the atmosphere. Sure, we had had large volumes on the
laws of storms, but the later revelations leave them shelved high
and dry on the shores and as useless as a wreck in a similar
condition; with the daily weather map before us we have no need to
even open these huge volumes; they are completely circumvented, and
only negative in value–to show how little was known of the subject
without the full and complete facts daily collected and spread
before us on the map published by the Weather Bureau.

In order to understand the color of our sky, we must understand
the subject which is so immediately connected with it and its
creation.

The earth is a sphere in space; generally speaking, it is
composed of land and water. These are two factors; the heat that it
derives from the sun forms a third factor; the three–land, water,
and heat–are essential to life, at least the higher conditions of
life which culminate in man. The old physical geography taught us
this much, but it was not able to go further and tell us why it was
cold or warm independent of the seasons; it could not explain why
it was at times as warm, and even warmer, half-way to the pole than
at the equator; why it was at times very warm in the extreme
northeast while very cold in the Southern States; cold in the
northwest when it was warm in the northeast, and warm in the
northwest when cold all along the upper Atlantic seaboard; it could
not forewarn us of storms. These and a host of other facts, which
the weather map makes as plain as astronomy demonstrates that
Jupiter is a planet, the new revelation, through the
instrumentality of the perfected telegraph system, makes
exceedingly plain to us if we will but seek the easily obtained
information.

The principal revelations of the weather map are the facts in
regard to the areas of high and low barometer, and the influence
they exert upon the climate of the globe.

These conditions–high and low barometer–move on general lines
from the west towards the east, or towards the rising sun, and
around the world in irregular belts. The centers of low barometer
are various distances apart, from a thousand to two thousand and
even more miles apart–call the average about two thousand
miles.

The clouds are formed from the moisture present by the action of
the sun’s heat. The direction of the wind is from the area of high
barometer to that of low. The nearer the winds approach the center
of “low” (low barometer), the more they partake of the lines of the
volute curve, or curve of the sea shell or water in a whirlpool.
High barometer is the atmospheric hill; low barometer is the
atmospheric valley. But time at present will not permit more than
these general statements; a close study of the weather map for a
season will reveal the beautiful minor details.

To the reader it may seem a long way round, yet in order to
fully understand the nature of the atmosphere which surrounds our
globe we must pay due attention to these newly discovered physical
laws.

The red sky which was so noticeable, in the fall of 1883, the
astronomers have told us was due to “meteoric dust” which was
produced by the volcanic eruption on the island of Java, August 27,
1883.

This “meteoric dust” they say combined with the atmosphere,
followed it around the earth, and caused the beautiful redness of
the sky at morning and evening. For one, I do not believe dust of
any description in the atmosphere would produce such an effect.

There is nothing luminous, transparent, or delicate about dust.
Dust would not remain in the atmosphere for months, it would settle
in a very short time, and if thick enough in the atmosphere to
obstruct the light of the sun it would be visible, discernible, to
the eye, and manifest on the face of nature. Years ago, before the
age of the weather map, we might have thought that the atmosphere
followed the surface of the earth like the water on a grindstone,
but it does not. As already seen, the wind is from the area of high
barometer to that of low, and there are many of these “low
centers.”

From the best calculation we can make at present, there would be
at least some six centers on an average between the center of the
United States and the island of Java. In addition to this there
would also be a number of belts of “low” centers, which would
complicate the thing threefold at least. At all these different
centers the winds would be blowing from all points of the compass
at the same time. Such winds would not be apt to bring the
“meteoric dust” from Java to the United States, either in an
easterly or westerly direction. But, it is said, “dust” has been
gathered.

How high from the surface of the ground has this dust
been gathered–at what elevation?

There is undoubtedly a little dust in the air most of the time,
but I do not think that it extends very high. Where it would be the
highest and most perceptible would be on the arid plans of Africa
and Asia, when the simoom is passing, or in the track of a
tornado. But from the multiplicity of these storm centers and the
varied winds they would produce even this dust could not travel
from Java to America.

Again, all clouds, no matter how high or how low, are affected
by the low centers, as the movement of clouds prove, and travel
from the “high” to the “low,” from and to all points of the
compass. High authority gives the heights of the clouds as follows:
lower clouds, 16,000 feet; upper clouds, 23,000 feet.

As all clouds, from the highest to the lowest, are affected by
the centers as above referred to, it follows that if this “meteoric
dust” follows the earth around, as it would have to do in order to
make good this theory, it would have to travel suspended in the
atmosphere above the upper clouds, or at a height of more than
23,000 feet, or at an elevation of over four miles!

Now, is it reasonable to believe that dust, however fine, will
remain in the atmosphere at that elevation for over six months?

As a side argument it is suggested that the smoke of the burning
woods, or few years ago in Michigan, caused as peculiar condition
of the atmosphere. This extensive fire was on a day when the area
of low barometer was on a high line of latitude and passing to the
eastward. This naturally took the smoke, which is far lighter than
dust, along with it. It mingled with the muggy condition of an
extensive “low,” and produced a yellowness of the atmosphere. This
however was of only a few hours’ duration, and was only visible in
favorable localities.

Here again we see the advantage of the weather maps; but for
this map we would never have been able to have satisfactorily
explained the peculiar phenomenon produced by the great Michigan
fire.

If the delicate redness of the sky is not caused by dust, what
is it caused by?

But for the weather map, I think we should still be in the dark
in regard to it.

In the first place, this redness is nothing new, only the
conditions are more favorable sometimes than at others. It has
always existed and always will exist, independent of earthquakes,
volcanoes, etc. Nature is ever changing; the movements of the
atmosphere more resemble the kaleidoscope than any thing else.

The summer and fall of 1883, the movements of “high” (high
barometer) over the United States were quite central and extensive,
causing this peculiar phenomenon over a wide extent of
territory.

We have no information of the condition of the barometer over
the other part of the world; we speak move particularly of the
United States; yet if certain conditions produce certain effects
here, it is quite safe to say that the same effects are produced by
the same cause elsewhere.

As now well established by the map, the surface wind is from the
area of high barometer to that of low–from the atmospheric hill to
the atmospheric valley.

The tendency of this is to free “high” of all clouds and
moisture; but then it is impossible to free “high” entirely of
moisture; a little will remain, and it is just this little, which
is highly rarefied, that produces the result. We look around us and
above, we see little or no evidence of evaporation, yet it is the
while going on. When the sun is immediately below the horizon,
where it will shine horizontally through the mass of light,
suspended moisture, the delicate presence of vapor heretofore
unnoticed is revealed. The action of the sun’s rays is the same as
when illuminating a well formed cloud–it is an embodiment of the
same principle, but the material is much more expanded. The
particles of suspended moisture are very fine, few and far between,
therefore the effect of the light upon it is more diffused and
transparent. It is much like looking through a piece of window
glass flatwise and endwise; flatwise we do not perceive any color;
endwise, from seeing through a greater mass, the glass has a very
perceptible green color.

We see the same idea also in the rising and setting sun and
moon. On a clear, cloudless night, when nothing seems to interfere
with the brightness of the stars, we cannot, by looking upward,
perceive any moisture present in the atmosphere; but if we cast our
eyes to the horizon, whereby we see through the mass of atmosphere
endwise, as it were, and note the appearance of the stars there, or
the rising or setting moon, we will see that the atmosphere there
gives a redness to the rising body, which it does not have when it
has ascended to mid-heaven. On a clear night, which is caused by
the presence of the area of high barometer, the moon when in
mid-heaven is of a clear, silver-white, and it is the same moon
that at the horizon was a deep red. The color of the moon has not
changed; it is simply the medium through which it is seen that
produces the difference in color.

Occasionally, on a clear, bright (“high”) night, when the moon
is full, prior to rising, when just below the horizon, it will so
illuminate this lower strata of atmosphere as to appear like a
great fire; the moon rises red, but its deep color gradually fades
as it rises, and when well up in the heavens we perceive that this
deep coloring was an illusion and merely the influence of its
surroundings. I never, though, knew of any one to attempt to
account for this by “meteoric dust;” and yet it is an embodiment of
the same principle. Place the sun where the moon is, and from its
far superior abundance of light we have a much grander display.

Under no other conditions or relations of the sun and earth is
it possible to have this phenomenon of the delicate red sky but
when a positive area of high barometer is passing and extends over
us. In order to produce this effect we must have the clear
atmosphere of high barometer, when there is a minimum of moisture
present. The action of the sun’s rays upon this extensive area of
slightly moist rarefied air is unconfined by clouds, and reaches
far and wide, and produces a delicacy of color which from no other
source or condition can be realized.

ISAAC P. NOYES.

Washington, D. C., 1884.

A THEORY OF COMETARY PHENOMENA.

To the, Editor of the Scientific American:

The following subject, substantially, was written more than a
year ago with a view to its publication. It was not, however, until
January of the present year that I sent a brief communication to
the Brooklyn Eagle, which was published Feb. 3, giving my
views in relation to cometary phenomena. With this I might remain
satisfied, were it not that the interesting paper by G. D. Hiscox,
published in the SCIENTIFIC AMERICAN SUPPLEMENT, Feb. 16, impressed
me with the idea that the theory I advanced might assist in
explaining others, if brought to the notice of those interested
through the columns of your valuable journal.

The theory that I advance to account for the several phenomena
relating to comets’ tails is, that comets are non-luminous,
transparent bodies; that they transmit the light of the sun; that
the transmitted light reflected by the particles of matter in space
constitutes the tails of comets. “Like causes produce like
effects.” By contraries, then, like effects must be produced by
similar causes; for, if an effect produced by a cause which is
known is similar to an effect produced by a cause which is not
known, the cause which is known must be similar to the cause which
is not known. This is true or not.

I submit the following experiments to substantiate the theory
advanced.

Partially fill a vial or a tumbler with water, hold it by the
rim, and move it around a lighted candle placed upon a table. A
shadow surrounding the transmitted light will be cast upon the
table. As the tumbler approaches the light, the shadow follows the
tumbler, and when receding the tumbler follows the shadow; and as
the tumbler is moved around the light, the shadow will swing round
from one side to the other. If the tumbler be held so that a puff
of smoke can be blown into the transmitted rays, the particles of
smoke will reflect the transmitted light, and will illustrate my
idea of what constitutes a comet’s tail. A dark band may be
observed in this stream of light, as also in the light cast upon
the table.

In these experiments, we see the effects produced by a cause
which is known; the effects are similar to those observed in the
tails of comets, the cause of which we do not know; but is it not
reasonable to assume that the cause is similar?

Assuming now that comets are transparent, can any other
phenomena peculiar to comets be accounted for upon this hypothesis?
Next to the tail itself, the curve is the most noticeable feature,
and if we consider the extraordinary length of these appendages,
the astounding velocity at which comets move in their orbits, and
the time that would elapse before a ray of light, emitted from the
nucleus, would reach the end of the tail, perhaps the curve–which,
if I am not deceived in my observations, always dips toward its
orbit–can be accounted for. If a comet moved in a direct line
toward the center of the sun, there would be no curve to the tail.
But taking Donati’s comet of 1858 as an example, the tail of which
was said to be about 200,000,000 miles long, a ray of light
traveling at the rate of 192,000 miles per second would be about
twenty minutes in going from the nucleus to the end of the
tail.

But during that time the comet would move in its orbit, say,
50,000 miles, and as light moves in a straight line, and other rays
are constantly emerging from the nucleus as it moves along in its
course, the result is that the tail has a curved appearance.

I have no data at hand regarding this comet, but what I have
said will serve to illustrate my ideas. Again, referring to this
comet, I remember to have read the statement of an astronomer that,
after passing round the sun, a new tail was formed opposite the
original one. Now, it seems to me that that is just what would
happen, for in moving round the sun the comet would travel say
3,000,000 miles; the greater portion of the tail then, would extend
millions of miles upon one side of the sun, while from the nucleus
upon the opposite side of the sun a new tail would appear to be
formed.

Upon this hypothesis, the extraordinary length of their tails
and the fact that stars are visible through the densest portion of
them is explained; as also the fact that they so rapidly disappear
from view when moving from the sun, the light received by them from
the sun being in proportion to their distance from it, and but
little of that reflected.

JOHN M. HUGHES.

Brooklyn, N. Y.

[FOR THE SCIENTIFIC AMERICAN.]

ON COMETS.

When we see a comet approaching the sun with its tail following
in the orbit of the nucleus, we have no great difficulty in
believing the common theory that a comet consists of nucleus
attracted toward the sun, while the tail is repelled; and that we
see the whole of it. But as it approaches the sun, difficulties
arise that make us doubt whether the theory be true.

Let us suppose a comet with a tail 50,000,000 miles in length,
and that it will require two days to pass round the sun. Now the
tail, being always in a line drawn through the center of the sun
and center of the nucleus, will, when it reaches the long axis of
the elliptical orbit, stand perpendicularly to the orbit of the
nucleus. That is, the extremity of the tail farthest from the sun,
in addition to its onward motion, has acquired a lateral motion
that has lifted it 50,000,000 miles in the first day of its
perihelion. The velocity of the extremity has been vastly
accelerated over that of the nucleus, and it has moreover a sheer
lift above the orbit of the nucleus. Now this lift is in opposition
to gravity; neither is it in consequence of any previous momentum,
for its velocity is accelerated and its previous momentum would be
a hindrance; nor is the lift in consequence of any repelling force
from the sun, for such force would be diminished in proportion to
the square of the distance, and the far end would be acted on less
than the nucleus end of the tail, whereas the velocity of the
former is increased a hundred fold over that of the latter. A polar
force in the comet would merely draw the comet into the sun. We
therefore find no force adequate for such a lift, but on the
contrary all the forces are opposed to it.

But if the first day of the perihelion overwhelms us with
difficulty, the second day will prove disastrous to the common
theory. For the extremity of the tail farthest from the sun will be
required to pass with lateral motion from its perpendicular
100,000,000 miles, so that it may be in advance of the nucleus and
again rest on its orbit. This orbit is an impassable line, and
therefore instantly arrests the prodigious lateral velocity of the
tail. That impassable orbital line is to it as solid and inflexible
as a wall of adamant. The motion so instantly arrested would be
disastrous to any tail, whether composed of gas, meteorites, or
electricity, whatever that may be.

Having shown that the common theory of comets is filled with
insuperable difficulties, I will again call attention to a theory
proposed about eighteen months ago in the SCIENTIFIC AMERICAN.

According to this theory, a comet consists of a nucleus and an
atmosphere, for the most part invisible, surrounding it on all
sides to an extent at least equal to the length of the tail. The
rays of the sun in passing through or near the nucleus are so
modified as to become visible in their further progress through the
cometic atmosphere, while all the rest remain invisible. What we
call the tail is merely a radius of the cometic atmosphere made
visible, and as the comet moves through space, only different
portions of the atmosphere come in sight, in obedience to the
ordinary laws of light. There is no difficulty in accounting for
the rise and fall of the tail at perihelion, nor for the tail
preceding the nucleus afterward.

The spherical theory accounts easily for the different forms of
tail seen in different comets. The sword shaped tails, at variance
with the common theory, can be accounted for by supposing a slight
difference in density or material in the cometic atmosphere, which
will deflect the light as seen. The comet of 1823, which cannot be
explained on the common theory, is very easily explained on the
spherical. That comet showed two tails, apparently of equal length,
which moved opposite to each other, and perpendicularly to the
orbit of the nucleus, and showing no signs of repulsive force from
the sun. On the spherical theory it is only necessary to suppose
such an arrangement of the nucleus as would reflect the rays of the
sun laterally; a slight modification of the nucleus would give not
only two but any number of tails pointing in different
directions.

It may be objected to the spherical theory that a tail
50,000,000 miles long would call for a sphere 100,000,000 miles in
diameter, and that would be too vast for our solar system. But it
is claimed for this sphere that it consists of the same material as
the so-called tail, and that it has the same capability of moving
among planets without manifest disturbance to either.

The sphere at the perihelion would envelop the sun, and as a
noticeable reduction is sometimes found in its so-called tail, the
cometic atmosphere may impart to the sun at that time whatever is
necessary to its use.

That there is something in common between the sun’s corona and
cometary matter was shown by the last solar eclipse observed in
South Pacific Ocean, where the spectrum of sun’s corona was found
to be the same as that of a comet’s tail. Are we to attribute in
any degree the different appearances of the sun’s corona to the
presence or absence of a comet at its perihelion? At the eclipse of
the sun seen in Upper Egypt two or three years ago, a comet was
seen close to the sun, but I have seen no account of the appearance
of the corona at that time.

FURMAN LEAMING, M.D.

Romney, Tippecanoe Co. Indiana.

FORMS OF IVY.

It is scarcely possible for us to bee too emphatic in our
praises of the most distinct forms of ivy, since but few other
hardy climbing plants ever give to us a tithe of their freshness
and variety. A good long stretch of wall covered with a selection
of the best green-leaved kind is always interesting, and never more
so than during the winter months, especially if at intervals the
golden Japanese jasmine is planted among them or a few plants of
pyracantha or of Simmon’s cotoneaster for the sake of their coral
fruitage. The large-leaved golden ivy is also very effective here
and there along a sunny wall, especially if contrasted with the
small-leaved kind–atropurpurea–which has dark purple or bronzy
foliage at this season. Of the large-leaved kinds, one of the most
distinct is canariensis, or large-leaved Irish ivy, and Raegner’s
variety, with leathery, heart-shaped foliage, is also handsome. The
birdsfoot ivy (pedata) is curious, as it clings to the stones like
delicate leaf embroidery, and for shining green leafage but few
equal to the one called lucida. The two other kinds sketched are
hastata and digitata, both free growing and distinct sorts.

VARIOUS FORMS OF IVY.
Heart-leaved Ivy (Hedera Raegenerana).
Glossy Ivy (H. lucida).
Arrow-leaved Ivy (H. hastata).

Ivy Leaves.–Common ivy is tolerably plentiful nearly
everywhere, but it is not common to find a good distinct series of
its many varieties even in the best gardens. Of all the different
forms of ivy, I think the large-leaved golden one of the best;
certainly the best of the variegated kinds. Raegner’s variety is
also very bold, its great glossy, heart-shaped leaves most
effective. Algeriensis is another fine-leaved kind, the form
dentata producing foliage even still larger when well grown. For
making low evergreen edgings on the turf, for carpeting banks, the
covering of bare walls and the old tree stumps, we have no other
evergreen shrub so fresh and variable, or so easily cultivated as
are these forms of the ivy green. Perhaps one reason why the finer
kinds of ivy are comparatively uncommon is the fact that a strong
prejudice exists against ivy in many minds. It is an erroneous
notion that ivy injures buildings against the walls of which it is
planted; it never injures a good wall, nor a sound house, but on
the contrary, hides and softens the stony bareness of the one and
adds beauty and freshness to the other.–The Garden.

VARIOUS FORMS OF IVY.
Finger-leaved Ivy (H. Itata).
Irish Ivy (H. canariensis).
Rira’s foot Ivy (H. pedata).

PROPAGATING ROSES.

In an article on this subject an English horticultural journal
describes the method pursued by a London florist. After stating
that out of a case containing 310 cuttings only five failed to
root, the article proceeds: The case or box is made of common rough
deal boards. It is five feet six inches long and one foot in depth.
Within half an inch of the top a groove is cut inside the box, into
which the glass is slid, after the manner of a sliding box lid. In
the end of the third week in July the box was placed in the kitchen
garden under the shadow of a high north wall; it was then about
half filled with good turfy loam, to which had been added a little
leaf mould and a good sprinkling of sharp sand. The soil was then
pressed down very firmly (the box being nearly half full when
pressed), and then thoroughly well soaked with rain water, and
allowed to stay uncovered until the next day. The next day good
stout cuttings were taken of all the roses, both tea and hybrid
perpetual, which it was desired to add to the stock. They were then
inserted closely and firmly in the soil, just over the bottom leaf,
the glasses were slipped on and puttied down; the grooves in which
the glass slid, and even the joints in the glass, being filled with
putty, so as to exclude the air. The whole thing completed, nothing
more remained to be done but to leave the box in its cool, shady
nook for five or six weeks, when the growing points of the free
starting kinds gave notice that the glasses might be removed, a bit
at a time, with safety. Nothing could be more simple, or demand
less skill, and the operation may be carried out successfully by an
amateur at any time during the season, when good firm cuttings can
be got, and when six weeks’ tolerably fine weather may be counted
on. The success of the whole thing depends on having the glasses
fixed so that they may not be removed until the cuttings are
rooted, and in placing the boxes in a shady place. So treated,
carnations and many of our shrubs and herbaceous perennials may be
propagated by unskilled persons with certainty, and without much
trouble.

A FEW OF THE BEST INULAS.

Of the fifty-six species of Inula described in scientific works,
probably not more than thirty are at present in cultivation in this
country, and those are chiefly confined to botanic gardens,
notwithstanding the fact that many of them are useful garden
plants. They are principally distributed throughout Southern
Europe, although we find them extending to Siberia and the
Himalayas; indeed, it is to the Himalayas we are indebted for the
kinds that are most ornamental. Some of the low-growing species are
extremely useful for the rockery, such as I. montana (the Mountain
Inula), a fine dwarf plant with woolly lanceolate leaves and dense
heads of orange-colored flowers, resembling in habit and general
appearance some of the creeping Hieraciums. It is a handsome and
desirable plant for the decoration of old walls and similar places,
where it can be a little sheltered from rain and drip. Another very
useful species for this purpose is I. rhizocephaloides, found
plentifully in the Himalayas. It is one of the prettiest Alpine
composites we have. It seldom attains more than from one inch to
two inches in height, forming a dense rosette of short, hairy, oval
leaves, in the center of which the bright purple involucres, in the
form of a ball, are extremely interesting. It is easily cultivated,
requiring, however, a rather snug nook, where it will not be
allowed to become too dry. It is best propagated from seed. Then
there is the woolly Inula (I. candida), a pretty plant with small
oval leaves, covered with a thick, silky down, and much in the way
of the white-leaved I. limonifolia, both of which are very
effective when grown in masses, which should always be low down
near the front of a rockery, or as an edging for a mixed border.
The glandular-leaved Inula (I. glandulosa), of which a good
representation is here given, is a beautiful hardy perennial. It is
a native of Georgia and the Caucasian Alps, near the Caspian Sea.
It is a rather robust-growing species, with large, bright,
orange-yellow flowers, varying from three to five inches in
diameter, the narrow and very straggly ray florets contrasting
nicely with the rather prominent disk. The leaves, although quite
entire, seem notched, owing to large black glands which form on
their margins. They are lanceolate, and clasp the stem. The plant
is very variable, both as regards robustness and size of flowers,
and this may in a measure account for the confusion existing
between it and I. Oculus-Christi.

The soil most suitable for the full development of I. glandulosa
is a strong, clayey, retentive loam; it does not thrive well in the
light shallow soils in the neighborhood of London, except in shady
positions. I. Hookeri is a free-flowering perennial, with pointed
lanceolate leaves, of a delicate texture, bright green, and very
finely toothed. The flowers, which are sweet-scented, are not so
large as those of I. glandulosa, and are produced singly, the ray
florets being, however, much more numerous, rarely numbering less
than thirty. It is found in abundance in rocky places in Sikkim,
where it replaces the nearly allied I. grandiflora, a dwarfer
species, with much shorter, shining leaves; both are very desirable
plants either for rockery or flower border work. The Elecampane (I.
Helenium) is an imposing, robust-growing species, having large,
broad leaves a foot or more in length. It grows from four feet to
five feet in height, and its thick, shaggy branches are crowned
with large yellow flowers. For isolating in woods this plant, is
very useful, and with the exception of Telekia cordifolia, it would
be hard to find a rival to it. It is, I believe, pretty extensively
used for planting in shrubberies, but unless they are thin and open
it is seldom seen to advantage. It is found wild or naturalized in
some parts of England. It flowers in June and July, and even into
August when the season has been favorable.

INULA GLANDULOSA (flowers deep yellow.)

For naturalizing in woods the following will be found useful,
viz., I. salicina, I. Oculus-Christi, I. squarrosa, I.
britannica, and many more, the true beauty of which can only be
realized in this way. With the exception of I. rhizocepbaloides,
they are all propagated by division with the greatest ease, or by
seed, which is best sown as soon as it is ripe.–D.K., The
Garden.

FRUIT GROWING.

By P.H. FOSTER.

In the first place, if you contemplate appropriating a portion
of your land for the raising of fruits, you should have the orchard
so situated that no large animals can run at large on the grounds.
Prepare your soil in the most thorough manner; underdrain, if
necessary, to carry off surplus water; dig deep, large holes; fill
in the bottom with debris; in the very bottom put a few leaves,
clam and oyster shells, etc., then sods; above and below the roots
put a good garden or field soil; do not give the trees fresh manure
at the time of setting, but the following fall manure highly with
any kind on top of the ground; dig it in the following spring; keep
the soil frequently worked during the summer, and, if convenient,
mulch with hay, straw, or leaves.

Now you are on the road to progress, provided you have made no
mistake in the selection of your trees. The purposes for which you
intend your fruit is highly important. You should well consider at
the outset if for family or market use. This is a business which
requires a long look ahead, for it is said, “He who plants pears
looks ahead for his heirs.”

Caution should be used in procuring your stock; little should be
planted that is not fairly tested on the Island, purchased of
parties who can be fully relied upon to give you what you want. Do
not buy your stock of parties who carry labels in their pockets to
make to order what you want out of the same bundle of trees.

Now, having your trees set out in a proper manner, of such
varieties as you desire, the next important step is to bring the
trees into usefulness. My plan is to use bone–fine bone–very
freely about every three years. Another important matter is that of
trimming. “Fire purifies,” and the knife regulates the grand
balance or equilibrium between roots and tops. In most cases the
top outgrows the roots, the consequence of which is an ultimate
weakness of the tree. It is thrown into excessive fruiting,
disease, and premature decay. To avoid this result, use the knife
when required. Thin out the inside branches when small, and if the
tree does not make a satisfactory growth, cut back half way to the
ground.

We will suppose that you have got your trees growing nicely, and
they have begun to bear fruit. There are other important steps to
be taken, which will be of little cost to you. Provide a wind-break
for the orchard. Evergreens answer the purpose, being a protection
against the wind. Having this matter attended to, there are other
enemies with which we must contend. I refer to the apple and peach
tree borers. The former will live in the tree for three years, if
unmolested; the latter, one year only. They are very easily
destroyed by looking over the trees and taking them out with a
knife; or maybe prevented from touching the trees by wrapping a
piece of felt paper, 8 inches wide, around the tree near the
ground, the bottom being covered with dirt and the top tied tightly
above. The pear is not generally disturbed by these insects–only
the apple, peach, and quince. We have another insect very
destructive to the plum, peach, cherry, and apple–the
curcutio, or plum weavel. This season for the first time in
twenty years we have gathered a small crop of that very desirable
plum, the Purple Favorite. We simply threw air-slaked lime over the
trees nearly every morning for from four to six weeks, from the
time the tree was out of bloom. Peach trees should be treated in
the same manner. Another method of fighting this insect is to
spread a sheet under the tree, and with a blow jar off the little
Turk and secure him on the sheet. But I consider the lime procedure
the less trouble and more effective. The tent caterpillar, which is
easily seen, should be destroyed at once. We have yet another
insect to contend with which infests the apple and pear, commonly
called the Coddling Moth, and the larva, the apple-worm
(Garpocapsa pomonella). The loss by the ravaaes of this
insect alone to the fruit growers of the United States fan hardly
be estimated, as in many cases the whole crop is rendered
worthless. Such a vast destruction of two of the most valuable
fruits the world produces should stimulate scientists in this age
of progress to discover an effectual remedy against such a gigantic
evil.

I have never yet discovered nor tried an effectual remedy
against this insect. The nearest I have approached his
extermination is in the following manner: After it has entered the
fruit and accomplished its damage, the time arrives when it has to
leave the fruit and hide itself in a quiet, secure position to
undergo the transition from the larva to the pupa state, which
requires, in the early part of the season, eight or ten days; after
this time the miller is hatched and is again ready to besiege the
fruit with its sting. The insect, being two-brooded in this climate
at least, if not disturbed, has an aggregating force to do mischief
the second time. The progeny for the succeeding year have alone to
depend on the security of this second generation of larvæ. As
they may often be found in bark of apple trees during winter, my
plan of destruction is, about the first of July to take woolen rags
long enough to wrap around the trees, and say four inches wide.
Each week I look over the trees, and destroy the worms secreted
under the rags and wherever I find them until the fruit is off the
trees. I have all the green fruit, of every kind, carefully picked
up as soon as it falls, thereby destroying many of the curculio as
well as the apple-worms.

One word upon the grape–the insect part of the question. The
Phylloxera vastatrix, or grape-vine louse, is already at
work on Long Island. It is found very difficult to raise many of
our fine, new grapes with us in consequence of the depredations of
this very minute insect, it being almost too small to be seen by
the naked eye. There has lately been discovered a remedy which is
entirely chemical and as yet but little disseminated. Very soon, no
doubt, a discovery will be made that will stay the progress of this
destructive enemy.

We should plant aplenty of cherry and small fruit trees to yield
feed for birds. In return they will assist us in our efforts to
preserve a bountiful supply of this health producing element.

COARSE FOOD FOR PIGS.

A recent subscriber wants advice how to feed pigs of 25 to 35
pounds weight, that are to be kept over winter and fitted for sale
at about six months old–whether coarse food will not help them as
much in winter as in summer. How roots and pumpkins will answer in
lieu of grass, and what can be fed when this green food is gone? He
has had poor success in growing young pigs on corn alone. He has a
reasonably warm pen for winter.

The question of food is constantly recurring, and this is one of
the best evidences of the advancement of the country in the
feeder’s art. When people are making no inquiry as to improved
methods in any direction, no progress can be made. There has been
more progress made in the philosophy of feeding during the last
thirty years than in the century and a half previous.

In pig feeding in the dairy districts, young pigs generally grow
up in a very healthy condition, owing to the refuse milk of the
dairy, which furnishes the principal food of young pigs. Skim-milk
contains all the elements for growing the muscles and bones of
young pigs. This gave them a good, rangy frame, and, when desired,
could be fed into 400 or 500 pounds weight. But the fault attending
this feeding was, that it was too scanty to produce such rapid
growth as is desired. It took too long to develop them for the best
profit. It had not then been discovered by the farmer that it costs
less to put the first hundred pounds on the pig than the second,
and less for the second than the third, etc.; that it was much
cheaper to produce 200 pounds of pork in six months than in nine
and twelve months. When it became evident that profit required more
rapid feeding, then they began to ply them continually with the
most concentrated food–corn meal or clear corn. If this was fed in
summer, on pasture, no harm was observed, for the grass gave bulk
in the stomach, and the pigs were were healthy and made good
progress. But if the young pigs were fed in pen in winter upon corn
meal or clear corn, the result was quite different; this
concentrated food produced feverish symptoms, and the pigs would
lose their appetite for a few days, drinking only water, which,
after a while, would relieve the stomach, and the pigs would eat
vigorously again. Now, had they been fed a few quarts of turnips,
carrots, beets, or pumpkins, to give bulk to the stomach, and
separate the concentrated food, no harm would have come. This gives
the gastric juice a free circulation through the contents of the
stomach, the food is properly digested and applied to the needs of
the body instead of causing fever by remaining in the
stomach.–Live Stock Journal.

METE KINGI.

Our engraving is a portrait of a familiar character in New
Zealand, chief Mete Kingi, who recently died at the age of one
hundred years. He was a fine specimen of the Maori race, the native
New Zealanders, a branch of the Malayo-Polynesian family. The New
Zealanders surpassed all other people in the art of tattooing, to
which their chiefs gave especial attention. Mete Kingi, as our
picture shows, was no exception. Tattooing on the face they termed
moko. The men tattoo their faces, hips, and thighs; the
women their upper lips; for this purpose charcoal made from kauri
gum is chiefly used. It has the blue color when pricked into the
skin, growing lighter in shade in the course of years. The subject
of our illustration embraced Christianity, and was much respected.
Our engraving is from the Illustrated Australian News.

THE LATE MAORI CHIEF METE KINGI.

LAKE TAHOE.

Some very interesting information by Prof. John Le Conte, is
given in the Overland Monthly, being the result of some
physical observations made by the author at Lake Tahoe, in 1873.
Lake Tahoe, also called Lake Bigler, is situated at an altitude of
6,247 feet in the Sierra Nevada Mountains, partly in California,
partly in Nevada. The lake has a length of 22 and a width of 12
miles. As regards its origin, the author regards it as a “plication
hollow,” or a trough produced by the formation of two mountain
ridges, afterward modified by glacial agency. The depth of the lake
is remarkable; the observations taken at ten stations along the
length of the lake gave the following depths in feet: 900, 1,385,
1,495, 1,500, 1,506, 1,540, 1,504, 1,600, 1,640, 1645. This depth
exceeds that of the Swiss lakes proper–Lake Geneva, for example,
has a maximum depth of 1,096 feet–but is considerably less than
that of Lakes Maggiore and Como, on the Italian side of the Alps. A
series of observations of the temperature of the water were taken
between the 11th and 18th of August. The average corrected results
are as follows:

The temperature, therefore, diminishes with increasing depth to
about 700 or 800 feet, and below this remains sensibly the same
down to 1,506 feet; or in other words, a constant temperature of
4° C. prevails at all depths below about. 820 feet. This is in
accordance with the theory, the temperature named being that of the
maximum density of water, and it confirms the recent observations
of Prof. Forel in Switzerland; he found, for example, that a
constant temperature of 4° C. was reached in Lake Zurich at a
depth of nearly 400 feet, the lake being then covered with 4 inches
of ice. The explanation of the observed fact that Lake Tahoe does
not entirely freeze over even in severe winters is found in the
extreme depth; and the fact that the bodies of drowned persons do
not rise to the surface after the lapse of the usual time is
explained by the low temperature prevailing near the bottom, which
does not allow the necessary decomposition to go forward so as to
produce the ordinary result.

The water of Lake Tahoe is remarkable both for its transparency
and beauty of color. A series of observations made at the close of
August or beginning of September showed that a horizontally
adjusted dinner plate of about 9½ inches diameter was
visible at noon at a depth of 108 feet. The maximum depth of the
limit of visibility as found by Prof. Forel, in Lake Geneva, was 56
feet. He showed, moreover, that this limit is much greater in.
winter than in summer, as explained in part by the greater absence
of suspended matter and in part by the fact that increase of
temperature increases the absorbing power of water for light. The
maximum depth of visibility in the Atlantic Ocean, as found by
Count de Pourtales, was 162 feet, and Prof. Le Conte states his
belief that winter observations in Lake Tahoe would place the limit
at even a greater depth than this. The author gives a detailed and
interesting discussion in regard to the blue color of lake waters,
reviewing in full the results of previous writers on the subject,
and concludes that while pure water unquestionably absorbs a larger
part of the red end of the spectrum, and hence appears blue by
transmitted light, the color seen by diffuse reflection is mainly
due to the selective reflection from the fine particles suspended
in it.

The last subject discussed by the author is that of the
rhythmical variations of level, or “seiches,” of deep lakes; he
applies the usual formula to Lake Tahoe, and calculates from it the
length of a complete longitudinal and of a transverse “seiche;”
these are found to be eighteen or nineteen minutes in the first
case and thirteen minutes in the second.

A catalogue, containing brief notices of many important
scientific papers heretofore published in the SUPPLEMENT, may be
had gratis at this office.

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