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Scientific American Supplement, No. 530, February 27, 1886 by Various

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wooden or metallic rings, whose mass is comparable to their own; and they
are, therefore, as regards elasticity, in an ill ascertained state. Yet a
diaphragm of the usual diameter (from 2 to 4 inches), and very thin (from
0.001 to 0.02 inch), clamped in this way by its edges, is capable of
vibrating when a continuous series of sounds are produced near it, by
means, for example, of a series of organ pipes. But the series of sounds
that it clearly re-enforces, in exhibiting a kind of complex nodal lines,
is plainly _discontinuous_; and how, therefore, would the existence of
such series suffice to explain the production of a _continuous_ scale of
isolated or superposed sounds, the chief property of the telephone?

(4.) The interposition of a plate of any substance whatever between the
diaphragm and the source of the vibratory motions in nowise alters the
telephonic qualities of the diaphragm, and consequently the _nature_ of
the motions that it effects--a fact that would be very astonishing if the
motions were those that corresponded to the peculiar sounds of the
diaphragm. This fact is already known, and I have verified it with mica,
glass, zinc, copper, cork, wood, paper, cotton, a feather, soft wax,
sand, and water, even in taking thicknesses of from 5 to 8 inches of
these substances.

(5.) We can put a diaphragm manifestly out of condition to effect its
peculiar scale of harmonics by placing small, unequal, and irregularly
distributed bodies upon its surface, by cutting it out in the form of a
wheel, and by punching a sufficient number of holes in it to reduce it
half in bulk. None of these modifications removes its telephonic

(6.) We can go still further, and employ diaphragms of scarcely any
stiffness and elasticity without altering their essential telephonic
properties, the reproduction of a continuous series of sounds, accords,
and timbres. Such is the case with a sheet iron diaphragm. It is very
difficult, then, to imagine a fundamental sound and its harmonics.

The conclusion from all this appears to me to be that the mechanism by
virtue of which telephone diaphragms perform their motions is at least
analogous to, if not identical with, that through which solid bodies of
any form whatever (a wall, for example) transmit to all of their surfaces
all the simple or complex successive or simultaneous vibratory motions,
of periods varying in a continuous or discontinuous manner, that are
produced in the air in contact with the other surface. In a word, we have
here a phenomenon of _resonance_. In diaphragms of sufficient thickness
this kind of motion would exist alone. In thin diaphragms the motions
that correspond to their special sounds might become superposed upon the
preceding, and this would be prejudicial rather than useful, since, in
such a case, if there resulted a re-enforcement of the effects produced,
it would be at the expense of the reproduction of the timbre, the
harmonics of the diaphragm being capable of coinciding only through the
merest accident with those of the sounds that were setting in play the
fundamental sound of the diaphragm. This is what experiment clearly

II. Let us now pass to the _magnetic role_ of the telephone diaphragm.
Such _role_ can be clearly enough defined by the following facts:

(1.) The presence of the magnetic field of the telephone in nowise
changes the preceding conclusions.

(2.) Upon farther and farther diminishing the stiffness and elasticity of
the diaphragm, I have succeeded in suppressing it entirely. In fact, it
is only necessary to substitute for it, in any telephone whatever, a few
grains of iron filings, thrown upon the pole of the magnet, covered with
a bit of paper or cardboard, in order to render it possible to reproduce
all sounds, and articulate speech with its characteristic quality,
although, it is true, with very feeble intensity.

(3.) In order to increase the intensity of the effect produced, it
suffices to substitute for the iron diaphragm a thin disk of any sort of
slightly flexible substance, metallic or otherwise, cardboard, for
example, and through the aperture of the usual cover of the instrument to
scatter over it from 11/2 to 3 grains of iron filings. In this way we
obtain an iron filings telephone. By properly increasing the intensity of
the magnetic field, I have been able to form telephones of this kind that
produced in an ordinary receiver as intense effects as those given by
the usual transmitters with stiff disks, and which, too, were reversible.
But for a field of given intensity, there is a weight of iron filings
that produces a maximum of effect.

We thus see that the advantage of the iron diaphragm over filings is
truly reduced to the presentation of a much larger number of magnetic
molecules to the action of the field and to external actions, within the
same volume. It increases the _intensity_ of the telephonic effects,
although for _the production_ of the latter with all their variety,
fineness, and perfection it is nowise indispensable. It suffices, after a
manner, to materialize the lines of force with iron filings, and to act
mechanically upon them, and consequently upon the field itself.

* * * * *



[Footnote: Note presented to the Academy of Sciences, November 16, 1885.]

On a former occasion I described some experiments that had led me to a
theory of the telephone transmitter; a few words will suffice to expose
that of the receiver.

Such theory gave rise during the first years succeeding the invention of
the telephone to a considerable number of investigations, the principal
results of which may be summed up in the two following points:

1. All the parts of a telephone receiver--core, helix, disk, handle,
etc.--vibrate simultaneously (Boudet, Laborde, Breguet, Ader, Du Moncel,
and others). But there is no doubt that by far the most energetic effects
are those of the disk. It has been possible to put the vibrations of the
core and helix beyond a doubt only by employing very energetic
transmitter currents, or very simplified and special arrangements of the
receiver (Ader, Du Moncel, and others).

2. In telephone receivers we may employ disks or diaphragms of any
thickness up to six inches (Bell, Breguet, and others).

From the first point it had already resulted that the diaphragm was no
more indispensable in the receiver than it was in the transmitter, as I
have already shown (_Comptes Rendus_, t. ci., p. 944); and, from the
second point, that there were other effects in a receiver than those that
could result from the transverse vibrations corresponding to the
fundamental sound and to the harmonics of the diaphragm.

So Du Moncel, basing a theory upon these two categories of facts,
asserted that the effects of the telephone receiver were principally due
to the molecular vibrations of the core of the electro-magnet (analogous
to those that had been studied by Page, De la Rive, Wetheim, Reis, and
others), super-excited and re-enforced by the iron diaphragm operating as
an armature.

This theory has certainly truth for a basis; but it is incomplete, in
that the molecular vibrations of the core are but a very feeble accessory
phenomenon, and not a prominent one. At all events, I believe that we
can, in a few words, and very simply, present the theory of the telephone
receiver by going back to the facts that served me as a basis for the
theory of the transmitter, and that result from studies made with
telephones of ordinary forms.

In fact, it is enough to remark that the iron filings telephone
transmitter described in a preceding article (_1. c_.) is reversible and
capable of serving as a receiver--not a very intense one, it is true, but
here it is a question of the _nature_ of the phenomena, and not of their
intensity. It at once results that in receivers, as in transmitters, the
rigidity of the iron diaphragm is in nowise indispensable for telephonic
effects, such as the production of continuous series of successive or
simultaneous sounds and of articulate speech.

The diaphragm serves but to increase the intensity of these effects, as
in the transmitter, by concentrating the lines of force of the field, and
by presenting a greater surface to the air--the necessary vehicle of
sound. When it is thick, the internal motions that it takes on in
consequence of variations in the field, and which are transmitted to the
surrounding air and the ear, are solely those of resonance. When it is
very thin, the peculiar motions resulting from its geometric form and its
structure may become superposed upon the preceding, because it may then
happen that the corresponding sounds remain within the limits of the
pitch wherein the human voice usually moves (from ut_{2} to ut_{5});
but then, also, as the harmonics of the voice in nowise coincide with the
proper sounds of the diaphragm, the intensity of the effects is obtained
at the expense of a good reproduction of the timbre. This is certainly
one of the causes of the nasal timbre of most thin-diaphragmed
telephones. By diminishing their thickness, we lose in quality what we
gain in intensity.

But even in this latter respect there is a maximum for receivers, as I
have already pointed out that there is for iron filings transmitters. For
a magnetic field of given intensity, there is, all things equal, a
diaphragm thickness that gives a maximum telephonic result. Such result,
which is analogous to those that occur in other electro-magnetic
phenomena, may explain the want of success of many tentatives made
somewhat at haphazard, with a view to increasing the intensity of
telephonic effects.

* * * * *


Dr. F. Hueppe, who has paid great attention to this subject, describes
five distinct organisms which he finds to be invariable accompaniments of
lactic fermentation. One of these he isolated on nutrient gelatine in the
form of white, shining, flat, minute beads. This organism has the power
of transforming milk sugar and other saccharoses into lactic acid, with
evolution of carbonic acid gas. It is rarely found in the saliva or
mucilage of the teeth. In these are two micrococci, both of which cause
the production of lactic acid, but which manifest differences in their
development under cultivation. There are also two pigment forming
bacteria, _Micrococcus prodigiosus,_ which produces intensely red spots,
and the yellow micrococcus of osteomyelitis. These five bacteria are so
different and so constant in their properties that they must, in Dr.
Hueppe's opinion, be regarded as distinct species. In addition to them
there is in milk an organism resembling _Mycoderma aceti_, which
transforms milk sugar into gluconic acid.

* * * * *


At last the new "Burgtheater" in Vienna is completed. We say "at last,"
for work was begun on this new theater more than ten years ago. One after
another, monumental architectural works have been erected, which are no
less grand and beautiful than this. They were finished long ago, and
given over to their respective uses--the Parliament buildings, the
"Rathhaus," the University; but Baron Hasenauer, who had charge of the
construction of this building, as well as of many others, could not bring
himself to the quicker _tempo_ of Messrs Hansen, Schmid, and Ferstel. The
citizens of Vienna were naturally impatient to see their beautiful
"Ringstrasse" completed, and only the Hasenauer buildings were needed to
make it perfect.


The building was built according to the plans of Semper and Hasenauer;
for, as in the other great buildings erected by Hasenauer, the new palace
and the museums, Semper's plans served as a foundation. All the modern
improvements in the architecture of theaters have been embodied in the
new theater, for the terrible catastrophe at the Ringtheater taught a
lesson which has not been forgotten, and the greatest care has been taken
to guard against fire.

The new "Burgtheater" stands directly opposite the imposing "Rathhaus"
(senate-house), and is separated from the same by a charming park; to
the right stands the University, and to the left the Houses of
Parliament. In order to be worthy of such company, and not be
overshadowed by these buildings, it was necessary that the theater should
be very grand. The most important requirements have been perfectly
fulfilled; beauty, elegance, appropriateness, and security against fire,
nothing has been neglected.

The principal part of the building stands out strongly, and is flanked on
either side by a pavilion-like wing. The audience room will accommodate
about two thousand people.

The public and the actors alike rejoice in the new Burgtheater, for which
they have waited so long.

* * * * *


It seems strange that book-printing and the book trade in general should
have developed so slowly in the busy city of Leipzig, where a university
was established as early as the beginning of the fifteenth century. The
first honorable mention of the printing of Leipzig was made during the
first decade of the sixteenth century, but it was not until the end of
the seventeenth century that the printing and publishing of books
received a notable impulse, which was given it by Messrs. J.F. Gleditsch
and Thomas Fritsche and Profs. Carpzov and Mericke, who published many
works of great typographical beauty.

From 1682 to 1700 ninety-one papers and periodicals appeared in Leipzig,
of which the _Acta eruditorum_ was the oldest, being the first German
scientific paper. At this time there were seventeen printing
establishments in Leipzig, and the seventy presses in use printed, on an
average, 2,000 bales of paper yearly.

One of the leading bookdealers, Philipp Emanuel Reich, won the
approbation of his fellow citizens by establishing the first Bookdealers'
Association at the time of the Easter Fair in Leipzig, in 1764, and it
was through his efforts that the Book Exchange or Fair was founded, which
has placed Leipzig at the head of the book trade; but several years
passed before this private undertaking become a public association. About
1834 a building was erected specially for a book exchange or bourse, but
this building was soon outgrown, and it was decided to build a new one
which should be adequate to the requirements of the institution.

A competition for designs for the new building was opened, and five
designs were presented, from which the plan of Messrs. Kayser and Von.
Grossheim, of Berlin, was selected. This design, which is shown in the
accompanying cut, taken from the _Illustrirte Zeitung,_ presents a
picturesque grouping of the different parts of the building, the main
building being on one street and the adjoining building on another
street. The roof, which forms a beautiful sky-line, is ornamented with
dormer-windows and little towers, there being a large tower on the main


To the left of the principal hall in the main building, which has three
large ornamental windows, there is a little hall, the central office, and
committee rooms, while the restaurant and the assembly rooms are on the
right. In the smaller building, through which there is a central
corridor, are the order rooms, assorting rooms, editorial sanctum of the
_Borsenblat_ (Bourse journal), and the post office, with telegraph

A low building runs almost the entire length of the main building, to
which it is joined at the right and left by side wings, thus inclosing an
open court. In this low building the exhibition rooms are arranged, and
in the middle is a vestibule through which these exhibition rooms, the
wardrobes, and the great hall can be reached. Over the vestibule is a

The arrangements for lighting, heating, and ventilation are excellent.
Steam heat is used, and the large hall is ventilated by the pulsation

The building, which is of red brick and sandstone, is worthy of holding a
place among the numerous beautiful buildings which have been erected in
Leipzig during the last few years. The cost of the building was limited
to 700,000 M., or about $160,000.

* * * * *

A correspondent has transmitted to the editor of _L'Union Pharmaceutique_
the prospectus of an oyster dealer who, besides dealing in the ordinary
bivalves, advertises specialties in medicinal oysters, such as "huitres
ferrugineuses" and "huitres au goudron." The "huitres ferrugineuses" are
recommended to anaemic persons, and the "huitres au goudron" are said to
replace with advantage all other means of administering tar, while of
both it is alleged that analyses made by "distinguished _savants_" leave
no doubt as to their valuable qualities.

* * * * *


Notwithstanding the unprecedented progress of the coal-tar dyestuff
industry during the past few decades, the time-honored indigo, logwood,
fustic, etc., have been only partly displaced by the coal-tar products in
wool dyeing. The cause is that, though the dyer handled many aniline
dyestuffs which dyed as fast against light as logwood or fustic, the dye
proved unsatisfactory for fulling goods, because it bled in the treatment
with soap and soda, and often more or less changed its tone. We intend to
render a service to our readers by calling their special attention to
some products of the coal-tar industry which are free from these defects
of aniline dyestuffs, and for which it is claimed that they far surpass
logwood, fustic, cudbear, etc., as to fastness against light, and
excellently stand fulling. We allude to the alizarine dyestuffs, which
have long since been introduced and are largely employed in cotton dyeing
and printing.

Alizarine, which has been extensively discussed in various articles in
our journal, is the coloring matter contained in the madder root. In
1869, two German chemists, Graebe and Liebermann, succeeded in
artificially producing this dyestuff from anthracene, a component of
coal-tar. The artificial dyestuff being perfectly pure and free from
those contaminations which render the use of madder difficult, it soon
was preferred to the latter, which it has at present nearly completely

The discovery of alizarine red was soon followed by those of alizarine
orange, galleine, coeruleine, and, in 1878, of alizarine blue.

The slow adoption of these dyestuffs in the wool-dyeing industry is
principally attributable to the deep-rooted distrust of wool dyers
against any innovation. This resistance, however, is speedily
disappearing, as every manufacturer and dyer trying the new dyestuffs
invariably finds that they are in no respect inferior to his fastest dyes
produced with indigo and madder, but are simpler to apply and more
advantageous for wool.

The alizarine colors are dyed after an old method which is known to every
wool dyer. The wool is first boiled for 11/2 hours with chromate of potash
and tartar, then dyed upon a fresh bath by 21/2 to 3 hours' boiling. All
alizarine colors (such as those of the Badische Anilin und Soda Fabrik,
of Ludwigshafen and Stuttgart; Wm. Pickhardt & Kuttroff, New York,
Boston, and Philadelphia, viz.):

Alizarine orange W, for brown orange,
Alizarine red WR, for yellow touch ponceau or scarlet,
Alizarine red WB, for blue touch yellow or scarlet,
Alizarine blue WX and SW, for bright blue,
Alizarine blue WR SRW, for dark reddish blue,
Coeruleine W and SW, for green, and
Galleine W, for dahlia,

are dyed after the same method, which offers the great advantage that all
these colors can be dyed upon one bath, and that by their mixture
numerous fast colors can be produced. On the ground of numerous careful
experiments, the writer recommends the following method, which gives well
developed and well fixed colors, viz.:

For 100 kil.--The scoured and washed wool is mordanted by boiling for 11/2
hours in a bath containing 3 kil. chromate of potash and 21/2 kil. tartar,
and lightly rinsed; when it can immediately be dyed. For 1,000 lit.
water, 1 lit. acetic acid of about 7 deg. Be. is added to the bath. If the
water is very hard, double the quantity of acetic acid, which is
indispensable, is added. Then the required quantity of dyestuff is added,
well stirred, the wool entered, and the temperature raised to boiling,
which is continued for 21/2 to 3 hours, that is, until a sample taken does
no longer surrender any color to a hot solution of soap. Loose wool and
worsted slubbing can be entered at 60 deg. C. (140 deg. F.). In dyeing yarn and
piece-goods, however, it is advisable to enter the bath cold, work for
about 1/4 hour in the cold, and then slowly to raise the temperature in
about one hour to the boiling point. With this precaution, level and
thoroughly dyed goods are always obtained. If the wool is entered in a
hot bath, or if it is rapidly brought to a boil, the dyestuff is too
rapidly fixed by the mordant and is liable to run up unevenly, and, with
piece-goods, more superficially. For the same reason the goods must
always be well wetted out before entering the bath.

We add some special recipes for the various colors, the mordant for all
of them being of 3 per cent. chromate of potash and 21/2 per cent. tartar
for 100 by weight of dry wool.

1. _Orange, Brown Touch_.
20 kil. wool, mordant with 600 grm. chromate of potash and 500 grm.
tartar, dye with 3 kil. alizarine orange W.

2. _Ponceau, Yellow Touch_.

20 kil. wool, mordant as for No. 1, dye with 2 kil. alizarine red WR 20
per cent.

3. _Ponceau, Blue Touch_.

20 kil. wool, mordant like No. 1, dye with 2 kil. alizarine red WB 20 per

4. _Dahlia_.

20 kil. wool, mordant like No. 1, dye with 5 kil. galleine W.

5. _Green_.

20 kil. wool, mordant like No. 1, dye with 6 kil. coeruleine W.

_For Piece-goods._

20 kil cloth, mordant the same, dye with 1 kil. 200 grm. coeruleine SW.

6. _Blue, Bright_.

20 kil. wool, mordant the same, dye with 6 kil. alizarine blue WX.

_For Piece-goods._

20 kil. cloth, mordant the same, dye with 1 kil. 200 grm. alizarine blue

7. _Blue, Dark and Red Touch_.

20 kil. wool, mordant like No. 1, dye with 6 kil. alizarine blue WR.

_For Piece-goods._

20 kil. cloth, mordant the same, dye with 1 kil. 200 grm. alizarine blue

Particular stress is to be laid upon the great fastness of the alizarine
dyes against light and fulling. Besides, these dyestuffs contain nothing
whatever injurious to the wool fiber. Sanders, which very much tenders
the wool, as every dyer knows, can in all cases be replaced by alizarine
red and alizarine orange, making an end to the spinners' frequent
complaints about too much waste.

Alizarine blue in particular seems to be destined to replace indigo in
the majority of its applications, having at least the same power of
resisting light and acids, and relieving the dyer of the troublesome,
protracted rinsings required for indigo dyed goods. Every piece-dyer
knows that the medium and dark indigo blue goods still rub off, even
after eight hours' rinsing; but alizarine blue pieces are perfectly dyed
through and clean after one hour of rinsing. Another advantage of
alizarine blue and the other alizarine dyestuffs is that they unite with
all wood colors, as well as with indigo carmine and all aniline
dyestuffs. A fine and cheap dark blue, for instance, is obtained by
mordanting the wool as above stated and dyeing (20 kil.) in the second
bath with 6 kil. alizarine WX and 2 kil. logwood chips; the wood is added
to the bath together with the alizarine blue WX, and the best method is
to put it into a bag which is hung in the bath.--_D. Woll.-Gew.; Tex.

* * * * *

Papier mache has come of late to be largely used in the manufacture of
theatrical properties, and nearly all the magnificent vases, the handsome
plaques, the graceful statues, and the superb gold and silver plate seen
to-day on the stage are made of that material.

* * * * *


The streets of "Old London" at the recent Inventions Exhibition at South
Kensington were paved with a material in imitation of old, worn bowlder
stones and red, herring-boned brickwork, all in one piece from one side
of the street to the other. The composition is made by Wilkes' Metallic
Flooring Company, out of a mixture consisting chiefly of iron slag and
Portland cement, a compound possessing properties which won the only gold
medal given for paving at that Exhibition. At the present time the
colonnade in Pall Mall, near Her Majesty's Theater, is being laid with
this paving, which is also being extensively used in London and the
provinces for roads, tramways, and flooring; the composition is likewise
sometimes cast into artistic forms for the ornamentation of buildings, or
into slabs for roofing, facing, and other purposes. The subway from the
Exhibition to the District Railway is laid with the same material.

The works of the Wilkes Metallic Flooring Company are in the goods yard
of the Midland Railway Company at West Kensington. The Portland cement,
before it is accepted at the works, is tested by means of an Aidie's
machine. The general strain the set cement is required to bear is 750 lb.
to the square inch. All samples which will not bear a strain of 500 lb.
are rejected. The various iron slags are carefully selected, and rejected
when too soft, and at the works a small percentage of black slag, rich in
iron, is mixed in with them. The lumps of slag are first crushed in a
Mason & Co.'s stone breaker, and then sifted through 1/8 in., 1/4 in.,
and 1/16 in. wire meshes into these three sizes for mixing. Next the
granulated substance is thoroughly well washed with water to remove
soluble matter and impalpable dust, and afterward placed where it is
protected from the access of dust and dirt. The washing waters carry off
some sulphides, as well as mechanical impurities. The Portland cement is
not used just as it, comes from the works, but is exposed to the air in a
drying room for about fourteen days, and turned over two or three times
during that period. The slag is also turned over three times dry and
three times wet, and mixed with the Portland cement by means of water
containing 5 per cent. of "Reekie" cement to make the whole mass set
quickly. The mixture is then turned over twice and put into moulds; each
mould is first half filled, and the mixture then hammered down with iron
beaters. The rest of the composition is then poured in, beaten down, and
the whole mould violently jolted by machinery to shake down the mixture
and to get rid of air holes. While it is still wet the casting is taken
out of the mould, its edges are cleaned, and after the lapse of one day
it is placed in a bath, of silicate of soda. Should the casting be
allowed to get dry before it is placed in this bath, no good results
would be obtained; it is left in the bath for seven days. When delicate
stone carvings have to be copied, the moulds are of a compound of
gelatine, from the flexible nature of which material designs much
undercut can be reproduced. For the foregoing particulars we are indebted
to Mr. William Millar, the working manager at West Kensington. Sometimes
the composition is cast in large, heavy slabs, moulded on the top to
resemble the surface of roads of granite blocks. A feature of the
invention is the rapidity with which the composition sets. For instance,
the manager states that a roadway was finished at the Inventions
Exhibition at seven o'clock one night, and at six o'clock next morning
four or five tons of paper in vans passed over it into the building,
without doing any harm to the new road. In laying down roads, much of the
preparation of the material is done on the spot, and the composition
after being put down unsilicated in a large layer has the required design
stamped upon its wet surface by means of wooden or gutta-percha moulds.
As regards the durability of the composition, Mr. T. Grover, one of the
directors, says that the company guarantees its paving work for ten
years, and that the paving, the whole of the ornamental tracings, and
some of the other work at Upton Church, Forest Gate, Essex, were executed
by means of Wilkes' metallic cement three years ago, and will now bear
examination as to its resistance to the action of weather. Some of this
paving has been down in Oxford Street, London, for more than six years.
Mr. A.R. Robinson, C.E., London agent of the company, states that the
North Metropolitan Tramway Company has about 25,000 yards of it in use at
the present time, and that the paving is largely used by the War Office
for cavalry stables. The latter is a good test, for paving for stables
must be non-slippery and have good power of resisting chemical action.

In the Wm. Millar and Christian Fair Nichols patent for "Improvements in
the means of accelerating the setting and hardening of cements," they
take advantage of the hydraulicity of certain of the salts of magnesia,
by which the cements set hard and quickly while wet. For accelerating the
setting of cements they use carbonate of soda, alum, and carbonate of
ammonia; for indurating or increasing the hardening properties of cements
they use chloride of calcium, oxide of magnesia, and chloride of magnesia
or bittern water; for obtaining an intense hardness they use oxychloride
of magnesia. The inventors do not bind themselves to any fixed
proportions, but give the following as the best within their knowledge.
For colored concretes for casts or other purposes they use Carbonate of
soda, 8.41; carbonate of ammonia, 1.12; chloride of magnesia, 0.28;
borax, 0.56; water, 89.63; total, 100.00. For gray concrete for any
purpose they use: Alum, 8.46; caustic soda, 0.28; whitening or chalk,
0.56; borax, 0.56; water, 90.14; total, 100.00. For floors or slabs _in
situ_ they add to cement, well mixed and incorporated with any required
proportion of agglomerate for a base, liquid composition of the following
proportions: Oxide of magnesia, 0.29; chloride of magnesia, 0.29;
carbonate of soda or alum, 4.74; water, 94.68; total, 100.00. Articles
manufactured by the invention are afterward wetted with chloride of
calcium and placed in a bath containing a solution of silicate of soda or
chloride of calcium. The strength of the chloride of calcium is equal to
about 20 deg. specific gravity.

C.A. Wilkes and William Millar's improved "metallic compound for
flooring, paving, and other purposes," has for its object to provide a
paving compound which is not slippery or liable to soften in hot weather,
which sets rapidly, and is durable. To three parts of blast furnace slag
are added one part of hydraulic cement and enough water to give the
proper consistency. To each gallon of water used is added one part of
bittern water--the dregs from the manufacture of sea salt--or one part
of brine, or about 5 per cent. of carbonate of soda, and 21/2 per cent. of
carbonate of ammonia. In the compound they sometimes use potash in the
proportion of about 5 per cent. of the carbonate of ammonia and carbonate
of soda, and when potash is used with bittern water or brine, the
proportion of the latter is correspondingly reduced. The compound is of a
blue gray color; but when a more striking color is desired, red or yellow
oxide of iron may be added. When more speedy induration is necessary,
they add about 1 oz. of copperas to every gallon of compound used. The
claim is the admixture of bittern water, carbonate of soda, and carbonate
of ammonia with the washed slag and cement.

Another improvement, by C.A. Wilkes, relates, in laying _in situ_ any
metallic or other materials for street roadways, to completing the
convenience thereof by roughening or grooving the surfaces. The concrete
is laid in a plastic condition upon a bed of hard core, broken stone, or
preferably rough concrete. For footpaths the material may be laid in
convenient sections, say 4 ft. to 8 ft. square and 2 in. to 4 in. thick;
and in order to allow for the expansion of the material during the
setting of the sections or subsequent variations in temperature, he packs
the joints between the sections with a layer of felting cloth or other
compressible material, thus forming expansion joints. Sometimes he
slightly roughens the surface of the material, to give better foothold to
pedestrians. Sometimes the grooving is made in imitation of ordinary
granite paving sets. In tramway pavement there are grooves to give a grip
to the horses' feet, and a slight camber between the rails. He states
that a great advantage in laying a pavement by the method is that, when
any repairs are necessary, a piece of the exact size can be manufactured
at the works, and stamped to the same pattern as the adjoining pavement,
then placed at once in position on the removal of the worn portion, thus
saving the time necessary for the setting of the concrete on the
spot.--_The Engineer_.

* * * * *


In the spring of 1883 a Mr. J.B. Thompson, of New Cross, London, patented
a new process of bleaching, the main feature of which consisted in the
use of carbonic acid gas in a closed vessel to decompose the chloride of
lime. The "chemicking" and "souring" operations he performed at one and
the same time. The reactions which took place in his bleaching keir were
stated by the inventor as follows:

1. Ca ) + CO_{2} = CaCO_{3} + Cl_{2}.

2. OH_{2} + Cl_{2} = (ClH)_{2} + O.

3. CaCO_{3} + (ClH)_{2} = CaCl_{2} + CO_{2} + H_{2}O.

That is, in 1 chloride of lime and carbonic acid react upon each other,
producing chalk and nascent chlorine; in 2 the nascent chlorine reacts
upon the water of the solution and decomposes it, producing hydrochloric
acid and nascent oxygen, which bleaches; in 3 the hydrochloric acid just
formed reacts upon chalk formed in 1, and produces calcium chloride and
one equivalent of water, and at the same time frees the carbonic acid to
be used again in the process of decomposing the chloride of lime.

When the process was first brought to the notice of the Lancashire
bleachers, it met with an amount of opposition. Some bleaching chemists
declared the process was not patentable, as fully half a century ago
carbonic acid was known to decompose chloride of lime. The patentee's
answer was emphatic, that carbonic acid gas had never been applied in
bleaching before. After some delay one of the largest English cotton
bleachers, Messrs. Ainsworth, Son & Co., Halliwell, Bolton, threw open
their works for a fair test of the Thompson process on a commercial

The result of trial was so satisfactory that a company was formed to work
the patent. Soon after this the well-known authorities on the oxidation
of cellulose, Messrs. Cross & Bevan and Mr. Mather, the principal partner
in the engineering firm of Mather & Platt, of Salford, Lancashire, joined
the company. For the last twelve months these gentlemen have devoted
considerable attention to improving the original contrivance of Thompson,
and a few weeks since they handed over to Messrs. Ainsworth the machinery
and instructions for what they considered the most complete and best
process of bleaching that has ever been introduced.

Recently a "demonstration" of the "Mather-Thompson" process of bleaching
took place at Halliwell, and to which were invited numerous chemists and
practical bleachers. Having been favored with an invitation, I propose to
lay before your readers a concise report of the proceedings.

It is usual in this country to give a short preliminary boil to the cloth
before it is brought in contact with the alkali, the object being to well
scour the cloth from the loose impurities present in the raw fiber and
also the added sizing materials. In the new process the waste or spent
alkaline liquors of the succeeding process are employed, with the result
that the bleaching proper is much facilitated. The economy effected by
this change is considerable, but in the next operation, that of
saponification, the new process differs even more widely from those
generally in use. In England, "market" or "white" bleaching requires a
number of operations. There is first the alkaline treatment divided into
the two stages or processes of lime stewing and bowking in soda-ash,
which only imperfectly breaks down the motes. There is consequently a
second round given to the goods, consisting of a bowk in soda-ash,
followed by the second and usually final chemicking. There is, therefore,
much handling of the cloth, with the consequent increase of time and
therefore expense.

Now, in the saponification process, the Mather-Thompson Company claim to
have achieved a complete triumph. They use a "steamer keir," the
invention of Mr. Mather. This keir is so constructed that it will allow
of two wire wagons being run in and the door securely fastened. At the
top of the keir is fixed a mechanical appliance for steaming the cloth.
The steamer keir process consists essentially in:

1. The application of the alkali in solution and in its most effective
form, viz., as caustic alkali, to each portion of fiber in such quantity
as to produce the complete result upon that portion.

2. The immediate and sustained action of heat in the most effective form
of steam.

Before the cloth is run into the steamer keir on the wire wagons, it is
saturated with about twice its weight of a dilute solution of caustic
soda (2 deg. to 4 deg. Twaddell = 0.5 to 1% Na_{2}O) at a boiling-temperature,
when in the steamer keir it is exposed to an atmosphere of steam at four
pounds pressure for five hours. This part of the process is entirely new.
The advantage of using caustic soda alone in the one operation, such as I
describe, has been long recognized, but hitherto no one has been able to
effect this improvement. It will be observed that the Mather-Thompson
process does away entirely with the use of lime and soda-ash in at least
two boilings and the accessory souring operation. In the space of the
five hours necessary for the steamer keir process the goods are
thoroughly bottomed and all the motes removed, no matter what be the
texture or weight of the cloth. After the cloth is washed in hot water it
is removed from the steamer keir, then follows a rinse in cold water, and
the goods are ready for the bleaching process.

In passing to the bleaching and whitening process, it may be necessary to
say that thus far the original Thompson process has been entirely
altered. Now we come to that part of the bleaching operation where the
essential feature in Thompson's patent is utilized. The patentee has
apparently thoroughly grasped the fact that carbonic acid has great
affinity for lime and that it liberates, in its gaseous condition, the
hypochlorous acid, which bleaches. The most perfect contact is realized
between the _nascent_ hypochlorous acid resulting from its action and the
fiber constituent in the exposure of the cloth treated with the bleaching
solution to the action of the gas. The order of treatment is as follows:

(1) Saturation with weak chemic (1 deg. Tw.), squeeze,
and passage to gas chamber.
(2) Wash (running).
(3) Soda scald.
(4) Wash.
(5) Repetition of 1, but with weaker chemic (1/2 deg. Tw.).
(6) Wash.
(7) Scouring.

The whole of the above operations are carried out on a continuous plan,
the machinery being the invention of Mr. Mather. The cloth travels along
at the rate of sixty or eighty yards a minute, and comes out a splendid
white bleach. The company consider, however, that it is necessary in the
case of some cloth to give a second treatment with chemic and gas, each
of thirty seconds duration, with an intermediate scald in a boiling very
dilute alkaline solution. Mr. Thompson originally claimed that the use of
carbonic acid gas rendered the employment of a mineral acid for souring
unnecessary. It is considered now to be advisable to employ it, and the
souring is included, as will be observed, in the continuous operation.

The new process for treating cloth differs materially from that
originally proposed by Mr. Thompson. His plan was to use an air-tight
keir in conjunction with a gas-holder. It is obvious that the
"continuous" process would not answer for yarns; Thompson's keir is,
therefore, employed for these and all heavy piece-goods.

Thus far I have given a concise outline of the Mather-Thompson process of
bleaching, which, it cannot be denied, differs materially from any system
hitherto recommended to the trade. Beyond doubt the goods are as
perfectly bleached by this process as by any now in use. The question
arises, What pecuniary advantage does it offer? Mr. Manby, the manager of
Messrs. Ainsworth, has informed me that he has bleached as much as ten
miles of cloth by the new process, and is, therefore, entitled to be
heard on the subject of cost. In regard to the consumption of chemicals,
he estimates the saving to amount to (in money value) one-fourth; steam
(coal), one-half; labor, one-half; water, four-fifths; time, two-thirds.

It might be well to contrast the process formerly employed by Messrs.
Ainsworth with that they have recently adopted:


Alkali. Bleach Acid Machine
(chemic). Washes.
/ Saturate.
(1) <
\ Steam.
/ (2) Continuous
| (chemic)
| machine
| (or keir if
(2) < for yarns,
| etc.).
| (2a) Machine or
\ pit sour.
(3) Wash up for


Alkali. Bleach. Acid Machine

(1) Lime stew. (1) Wash.
(2) Sour. (2) "
(3) Gray bowk (3) "
(soda ash).
(4)I Chemic. (4) "
(5) Sour. (5) "
(6) White bowk. (6) "
(7)II Chemic. (7) "
(8) Sour. (8) "

It will be understood that 2 and 2a are merged into a single process by
using the "continuous" machine. Of course, it will be understood that the
cloth has in each case to be cleansed from size and loose impurities. The
"Mather-Thompson" Company claim that their system takes twelve hours in
the case of "market" or "white" bleaching. They reckon eight hours for
the steaming process and four for bleaching and washing. This has to be
compared with the old system, which generally takes forty hours, made up
as follows: 8 treatments with reagents and the necessary washings, the
former taking four hours and the latter one hour each.

The "Mather-Thompson" system has created considerable commotion in
English bleaching circles. It is generally considered that the bleachers
throughout the whole country will be compelled to adopt it, so great is
the saving in time and cost. In commencing a bleachery, the cost of
plant by this system is, I understand, less than by the old
processes.--_Textile Colorist_.

* * * * *


By Prof. C.W. MacCord, Sc.D.


We are free to express the opinion at the outset, that for various
reasons the draughtsman is likely to gain very little advantage by the
use of mechanical devices for describing mathematical curves by
continuous motion. Such instruments are as a rule not only complicated
and expensive, but cumbersome and difficult of adjustment. It may be
suggested, _per contra_, that these objections do not apply to the
familiar combination of two pins and a string, for tracing the
"gardener's ellipse." But we question the propriety of classing a string
among strictly mechanical devices; it has its uses, to be sure, but in
respect to perfect flexibility and inextensibility it cannot be relied on
when rigid accuracy is required in drawing any of the conic sections.

[Illustration: FIG. 1.]

Nevertheless, the construction of such apparatus affords a study which to
some is fascinating, and even in the abstract is not devoid of utility.
In each case a definite object is presented, and usually a choice of
methods of attaining it; success requires a thorough knowledge of the
properties of the curve in hand, while ingenuity is stimulated, and
familiarity with expedients is cultivated, by the effort to select the
most available of those properties, and to arrange parts whose motions
shall be in accordance with them. Such exercise of the inventive
faculties, then, is good training for the mechanician. And it must not be
forgotten that a mechanical movement thus devised for one purpose very
frequently is either itself applicable to a different one, or proves to
be the germ from which are developed new movements which can be made so;
the solution of one problem sometimes furnishing a hint or clew of great
value in dealing with another.

[Illustration: FIG. 2.]

We proceed, then, to describe a few instruments of this kind, which we
believe to be new, in the hope that in the manner just pointed out they
may render a greater service than that for which they are directly

The first of these, shown in Fig. 1, is for the purpose of describing the
hyperbola. The properties of the curve, upon which the action of the
instrument depends, are illustrated in Fig. 2, where MM, NN, are the two
branches of an hyperbola; C the center; AB the major axis; F and F' the
foci. If now a tangent TT be drawn at any point as P of either branch,
and a perpendicular let fall upon it from the nearer focus F be produced
to cut at G a line drawn from P to the farther focus F', then this
perpendicular will cut the tangent at a point I upon the circumference of
a circle described about C upon AB as a diameter, and also the distance
F'G will be equal to AB.

In Fig. 1, then, we have a crank CI, whose radius is equal to CB, half
the major axis, turning about a fixed center C. Upon the crank-pin I is
hung, so as to turn freely, a rigid cross composed of a long slotted
piece TT, in which slides a block, and two cylindrical arms at right
angles to it and in line with each other, the axis EE passing through I.
The arm on the right slides through a socket pivoted at the focus F; the
one on the left slides through a similar socket, which is pivoted at G to
a third socket longer than the others, which again is pivoted at the
focus F'; the distance F'G being equal to AB. Through this long socket
slides a rod KP, the end P being formed into an eye, by which this rod is
pivoted to the block which slides in the long slot, and thus controls the
motion of the block; and the pivot at P is centrally drilled to carry the
pencil. It is thus apparent that the center line of the slot TT must in
all positions be tangent to the hyperbola PBR, which will be traced by
the pencil, whose motions are so restricted as always to satisfy the
conditions explained in connection with Fig. 2.

The apparatus as thus represented does not at first sight appear unduly
complicated. But in order to render it adjustable, so that hyperbolas of
varying eccentricities and on different scales may be drawn with it,
several parts not here shown must be added. A frame must be provided, in
which to arrange supports for the pivots at F and F', and these supports
connected by a right and left handed screw, or equivalent means of
altering the distance between the foci; the crank CI and the socket F'G
must be of variable length, and these in each case would require to be
carefully adjusted. So that, as we stated in the beginning, it is
questionable whether a draughtsman of ordinary skill could draw the curve
any more readily by the aid of such a piece of mechanism than he could
without it; but it may claim a passing notice as a novel device, and the
first one, we believe, for describing the hyperbola by a combination of
rigid parts.

* * * * *



As Microscopist of the United States Department of Agriculture, I am
frequently called upon to make investigations as to the character of
textile fibers and fabrics, not only for the public generally, but also
for several departments of the Government.

Textile fibers are presented both in the raw and as articles of
manufacture. In the latter case they may have been dyed, stained, or
painted. It is obvious that under these conditions the fibers should be
subjected to chemical reaction to bring them as nearly as possible to
their normal condition.

Considering how well the structures of the common textile fibers of
commerce--cotton, flax, ramie, hemp, jute, Manila hemp, silk, and
wool--have been investigated and minutely described by able and exact
microscopists, I will in this paper confine myself chiefly to such
experiments as I have personally made with textile fibers, treating them
with chemical agents while under the objective.

While I am aware that this method is not wholly new, I am satisfied that
comparatively little work has been done in this direction, and that a
wide field is still open for future research.

As microscopists, we have to fortify ourselves in every way that will
sustain, by truthful work, the value of the microscope as a means of
research, sometimes conducting our experiments under the most trying
circumstances. Fibers may be so treated by experts as to make it
difficult to determine how their changed appearance has been effected,
and it may happen in this age of experiment and of fraud that important
decisions in commercial transactions and in criminal cases may depend on
our observations.


A case in point will illustrate this. While Dr. Dyrenforth was chief of
the chemical division of the U.S. Patent Office, a person applied for a
patent on what he called "cottonized silk," inclosing specimens. He
claimed that he had discovered a mode of covering cotton fiber with a
solution of silk which could be woven into goods of various kinds; in
order to satisfy the public of the reality of his invention, he placed on
exhibition, in various localities, specimens of silk-like goods in the
form of ribbons in the web and skeins of thread, representing them to be
"cottonized silk."

Dr. Dyrenforth was not satisfied that the so-called discovery was an
accomplished fact, and he forwarded a few fibers of the material to the
division of which I have charge for investigation. I subjected them to my
usual tests, and found them to consist of pure silk, and I so reported to
Dr. Dyrenforth, who rejected the application for a patent. The microscope
was thus usefully employed to protect capitalists from imposition.


It may be well to state briefly the methods I employed in detecting the
real character of the material. The fibers were first viewed under plain
transmitted light, secondly, polarized light and selenite plate. Since
silk and cotton are polarizing bodies, "cottonized silk," if such could
be made as described, would give, in this case, the prismatic colors of
both fibers, and the complementary colors would differ greatly because of
the great disparity of their respective polarizing and refractive powers.

The fact will be observed that a cotton fiber presents the appearance of
a twisted ribbon when viewed by the microscope, while silk, owing to its
cylindrical form, cannot twist on itself. It should also be considered
that the diameter of "cottonized silk," so called, would be greater than
that of a fiber of silk, because the silk solution would have to be
applied to an actual thread of cotton, and not to a single cotton fiber,
by reason of the shortness of the original hairs of the latter. Were a
single fiber of such a combination put under a suitable objective, and a
drop of nitric acid brought in contact with the fiber, it would be seen
that the acid would destroy the silk and leave the fibers of cotton
untouched, the latter being insoluble in cold nitric acid. The action of
muriatic acid is similar in this respect. Were a fiber of cotton present
and a drop of pure sulphuric acid placed on it, followed quickly by a
drop of a transparent solution of the tincture of iodine, a peculiar
change in the fiber would take place, provided the right proportion of
acid be used. Cotton fiber, and especially flax fiber, under such
conditions, forms into disks or beads of a beautiful blue color.

Fig. 1 represents a cotton fiber, and 2, 3, 4, 5 those of flax, as they
appear under the acid treatment. Every textile amylaceous fiber is
convertible into these forms, more or less, by strong sulphuric acid. The
fibers of cotton, flax, and ramie are examples of amylaceous cellulose,
that is to say, these fibers are converted into starchy matter by
treatment with the last-named acid. Therefore combinations of these
fibers in any composition of non-amylaceous fiber (ligneous or woody
fiber) will be dissolved, leaving the latter unharmed; the woody fibers
remaining will prove suitable objects for examination under the


Again, it might be important to know whether a certain pulp or
composition contained flax in combination with cotton. The composition
might be of such a well-digested character as to destroy all appearance
of normal form, that is to say, the "twisted ribbon" character of cotton,
as well as that of the cylindrical and jointed characteristic of flax,
might be lost to ordinary view. In this case make a watery solution of
the pulp, spread it out thinly on a glass slide 3 inches by one, draw off
any superfluous water, then add one or two drops of a strong solution of
chromic acid to the preparation, and place over it a glass cover; when
viewed by the microscope, any portion of the flax joints present will
appear of a dark brown color; a solution of iodine has a similar effect.
The brown portions of the joints are nitrogenous in character; cotton
fibers are devoid of nitrogen.

[Illustration: Figs. 1, 2, 3, 4, 5.]


A chemist of the Department of Agriculture had once occasion to make
experiments with flax fibers, his object being to make them chemically
pure; and to this end he treated them with excess of bleaching agents,
thus rendering them of a beautiful white, silky appearance, to the naked
eye; but when I examined them under the microscope, I found the brown
nitrogenous matter of the joints still present, and on using the chromic
acid test, they became deeply stained. A chemical solution of flax
therefore would prove for some purposes undesirable, owing to the
presence of this ligneous matter. A chemical solution of cotton which is
destitute of ligneous matter will give a chemically pure solution. Cotton
is therefore better adapted than flax for collodion compounds.


It is known that when wool is treated with the sulphuric acid of commerce
or in strong dilute sulphuric acid, the surface scales of the fiber are
liberated at one end, and appear, under a low power, as hairs proceeding
from the body of the fibers. Wool may remain thus saturated in the acid
for several hours, without appearing to undergo any further change, as
far as is revealed by the microscope. When treated in mass in a bath of
sulphuric acid, strength 60 deg. B., for several minutes, and afterward
quickly washed in a weak solution of soda, and finally in pure water and
dried, it feels rough to the fingers, owing to the separation of the
scales. I have preserved a small quantity of wool thus treated for the
last twelve years, my object being to ascertain whether the chemical
action to which it was exposed would impair its strength. As far as I can
observe, without the aid of the proper tests, it seems to have retained
its original tenacity. Wool thus treated seems to possess the property of
resisting the ravages of the larvae of the moth. This specimen, although
openly exposed for the period named, suffered no injury from them. Under
the microscope, the lubrications appear to have resumed their natural
position, and appear finer.

From these experiments it would seem not improbable that a new article of
commerce might be produced from wool thus treated, considering that it
seems to be moth-proof.

I find in practice that when sable brushes are washed in a weak solution
of pure phenic alcohol and afterward in warm water, the moth worm will
not eat them. In this way I preserve sable brushes. I mention this
chemical fact because it shows that a change of this material is brought
about by the phenol as to its edibility, and this may explain why wool
treated with sulphuric acid is rendered moth-proof.

I find that when brain matter has been subjected to a solution of weak
phenic alcohol, weak alkaline solutions afterward applied fail to
separate its nerve-cells on the process of maceration. (This is probably
owing to its albuminoids being coagulated by the action of the phenol.)
When brain matter is subjected to a weak solution of soda alone, the
nerve-cells are easily separated by maceration, and well adapted for
microscopic use.


The fibers of dyed black silk may be viewed with interest under the
microscope. If a few threads of its warp are placed on a glass slide, and
one or two drops of concentrated nitric acid placed in contact with them,
the black color changes first to green, then to blue; a life-like motion
is observed in all the fibers; they appear marked crosswise like the
rings of an earthworm; the surface of each fiber appears loaded with
particles of dyestuff; finally the fibers wholly dissolve in the acid. If
we now treat a few threads of the weft in the same manner, a similar
change of color takes place. When the fibers assume the blue color, a
dark line is observed in the center of each, running longitudinally the
whole length; this dark line is doubtless the dividing line of the two
original normal threads formed directly by the two spinnerets; the dark
air line or shadow finally breaks up, and in the course of a few minutes
the silk is wholly dissolved. Were ramie, cotton, flax, or hemp present,
they would be observed, as all their fibers remain unchanged under this
treatment. If wool be present, rapid decomposition will follow, giving
off copious fumes of nitrous acid, allowing, however, sufficient time to
observe the separation of the scales of the fibers and to demonstrate by
observation under the microscope that the fibers are those of wool.

In making these experiments it is not necessary to use a glass disk over
the treated fibers. If a disk or cover is pressed on them while
undergoing this treatment, the life-like motion of the silk will not be
so apparent.

* * * * *


Mr. John Frew, Langloan Iron Works, Coatbridge, has been successful in
perfecting a most ingenious pyrometer, an instrument which is capable of
continuously indicating every variation of temperature with a remarkable
degree of correctness. This instrument, which we here illustrate, has
already become known to a number of proprietors and managers of blast
furnaces; and on the occasion of the members of the Iron and Steel
Institute visiting Coatbridge, in connection with the meeting of that
body which was held in Glasgow last autumn, many persons became
interested in its construction and in the practical determination of
blast temperatures by its readings. Furthermore, Sir William Thomson has
expressed himself as being highly delighted with it on account of the
manner in which its use illustrates various beautiful scientific

The leading principle on which the construction of this pyrometer has
been based is the well-known law of the expansion of gases. Referring to
our engraving, it will be seen that at A is a pipe through which air from
the cold blast main is admitted into another and larger pipe, B, which
reaches nearly to the bottom of a water cistern, C. By means of the inlet
and outlet pipes, D and E, the height of the water in the cistern is
maintained at a uniform level. In this way there is provided a head of
water which retains within the pipe, B, a constant pressure of air,
equivalent to the head of water between the open end of that pipe and the
overflow at E. Any excess of pressure is prevented by means of the
open-ended pipe, which permits the air to escape by the central tube.
This latter prevents the agitation caused by the upward rushing air from
disturbing the level of the water in the cistern; and in order further to
assist this, the central tube is filled loosely in its upper part with
lead bullets or other suitable materials supported on a perforated plate.
The water level in the cistern is indicated by means of a glass gauge,
which is represented at G. To the upper end of the pipe, B, another pipe,
H, is attached. This is required for conveying the cold air to the
pyrometer proper, for the piece of apparatus above described is simply an
arrangement for securing a flow or current of air at constant pressure.

At any point where it is desired to fix a pyrometer, a connection is made
with the pipe last spoken of, by means of a small pipe such as is
indicated at J, into which is fixed a platinum or other metallic nozzle
of small bore, as shown at K. To this same pipe there is attached a
solid-drawn copper spiral heater or worm, L, which is fixed into the
place or the material the temperature of which it is desired to indicate.
Into the outlet of this worm another similar but larger nozzle, M, is
fixed. At N is shown a small pipe which is connected with the pipe, J, at
any convenient point between the inlet nozzle, K, and the spiral heater,
L. The other end of this pipe passes through the India rubber stopper of
a small cistern or bottle, O, which, when in use, is about two-thirds
filled with a colored liquid. It will be seen that the tube, N, only
passes through the stopper, so that it may convey pressure to the surface
of the liquid. At P is a glass tube which also passes through the stopper
and then to the bottom of the colored liquid; and as its upper end is
open, any variation of pressure in the spiral heater is directly
transmitted to the indicating column of colored liquid.

[Illustration: FREW'S PYROMETER.]

The operation of the instrument is as follows: As the cold blast used in
the apparatus would be useless for the working of the pyrometer if taken
direct from the cold blast main, owing to its irregularity of pressure,
the regulator that has been described is employed, and by its means an
absolutely steady flow of cold blast air at an unvarying pressure is
secured. The diameters of the inlet and outlet nozzles are so nicely
adjusted that, so long as both are at the same temperature, the outlet
nozzle, which is open to the atmosphere, will pass all the air that the
inlet nozzle can deliver without disturbing the pressure in the cistern,
O; but if heat be applied to the circulating air through the walls of the
spiral heater, the air expands in volume, and is unable to pass through
the outlet nozzle in its heated condition as rapidly as it is delivered
cold by the inlet nozzle. The consequence is that an increase of pressure
takes place in the apparatus between the two nozzles, and it is this
pressure that indicates the amount of heat that the air has taken up from
the hot blast pipe, in which the spiral heater is fixed. Then, again, as
this pressure is directly transmitted to the indicating liquid in the
cistern and the vertical tube immersed in it, a rise takes place in the
column which is in exact proportion to the expansion of the current of
blast passing through the spiral heater.

The method of graduating the indicator scales of the Frew pyrometer is
worthy of special notice. When the apparatus is fitted up, and before it
is permanently fixed in position, the spiral heater is placed in cold
water of known temperature, and the point noted at which the colored
liquid stands in the indicator tube. The water is then boiled, and the
rise in the liquid in the tube is again noted. Suppose, in the first
instance, the cold water temperature to be 62 deg. Fahr., and that, from
this point up to 212 deg. Fahr., the liquid to have risen 21/4 in. in the
tube; this is equal to 11/2 in. per 100 deg. Fahr., and from these data a
scale is constructed, the correctness of which is easily verified by
transferring the spiral heater into an air bath or oil of high boiling
point, and then comparing the readings of the pyrometer scale with those
of a mercurial thermometer placed alongside of the spiral heater. By this
means it can be clearly demonstrated that, up to the highest point to
which it is safe to use a mercurial thermometer, the readings of the
pyrometer scale and that of the thermometer are identical.

While this pyrometer is particularly valuable for indicating the
temperature of hot blast stoves of every description, there are doubtless
many uses that will suggest themselves to persons engaged in various
industrial arts and manufactures. The apparatus is neat and substantial
in its parts, while it occupies very little space, is not at all liable
to derangement, and is entirely automatic in its action. A number of the
instruments have been in continuous use at the Langloan Iron Works, with
the most satisfactory results, for about eight months. The temperatures
they are graduated for vary according to the furnaces with which they are
connected and the kind of work to which these are

* * * * *

An exchange gives the following very simple way of avoiding the
disagreeable smoke and gas which always pours into the room when a fire
is lit in a stove, heater, or fireplace on a damp day: Put in the wood
and coal as usual; but before lighting them, ignite a handful of paper or
shavings placed on top of the coal. This produces a current of hot air in
the chimney, which draws up the smoke and gas at once.

* * * * *




Since the emulsion process has taken root, no improvement has awakened
such a lively, steadily increasing interest as photography of colored
objects in their correct tone proportions; a process which makes it
possible to reproduce the warmer color-tones, particularly yellow,
orange-red, and yellow-green, in their correct light value as they appear
to the eye.

In professional circles, as also among the public, the value of this
invention cannot possibly be underestimated; an invention with which a
new epoch in photography may begin, and by which the handsomest results,
particularly in reproductions of oil paintings, can be attained. But in
portraiture, as well as in landscape photography, recourse must also be
had to orthochromatic plates to obtain effective pictures, particularly
as plates can now be produced in which the relative sensitiveness closely
resembles that of the ordinary emulsion plate. Although a good deal has
been written about this subject, none of these sometimes excellent
treatises contains a complete and generally comprehensive formula for the
production of color-sensitive plates, and this circumstance causes me to
publish my own experiences.

The following coloring matters are particularly recommended in the
several publications as preferable:

Eosine yellow and eosine blue shade, iodine cyanin, erythrosine, methyl
violet, aniline violet, iodine green, azalein, Hoffmann's violet, acid
green, methyl green, rose bengal, pyrosine, chlorophyl, saffrosine,
coralline, saffranine, etc.

Particularly important is the correct concentration. The most excellent
color matters make the plates oftentimes quite useless by an incorrect
proportion of concentration. If this should be too strong, the total
sensitiveness will sink (decrease); but when too weak, the color
sensitiveness is much reduced.

This fault, particularly, cannot be corrected during washing, but I have
mentioned, at the end, how such overcolored emulsion can be made of use
before wetting (flowing).

By the addition of some coloring matter to the emulsion, the light
sensitiveness of the film toward some individual colored rays is
increased, but the sensitiveness for the stronger refractive rays is, as
a rule, generally reduced. The result is a loss of the total
sensitiveness for white light. Color-sensitive plates are therefore less
sensitive to light than ordinary plates of the same origin.

The action of the coloring matter depends also very essentially upon the
emulsion. If the emulsion contains iodide of silver, it has a greater
sensitiveness for light blue and blue-green light. At all events, the
iodide combination must not amount to more than one or two per cent., a
small quantity of iodine acting much better upon the total sensitiveness
of the plates than can be obtained by pure bromide of silver emulsion.

Methyl violet, rose bengal, and azalein act perceptibly in 1/10000 per
cent. upon yellow sensitiveness. Eosine and its varieties, eosine yellow
shade, or eosine J, pyrosine J, erythrosine yellowish, may all be noted
as very good sensitizers for green, yellow-green, and eventually for
yellow. The bluish shades of eosine colors, on the contrary, have an
absorption band further in the yellow. This is also the case with the
blue shade eosine (eosine B) and the most bluish of all eosines, the
bengal rosa. Of both eosines, yellow shade and blue shade, the latter
gives a little more intensity.

Although the eosine permits a large limit in the quantity, it will reduce
the sensitiveness greatly in larger quantity.

If eosine solution is mixed with bromide of silver emulsion, which is
entirely free from nitrate of silver, no eosine silver can form; it acts,
therefore, only as an optical sensitizer.

Of the several kinds of cyanin, chlorosulphate, nitrate, and iodide, the
latter acts best, as stated by Eder.

Schumann has already said that one drop of cyanin solution, 1 to 2,500 to
61/2 c. c. emulsion, already acted as sensitizing in orange; five to ten
drops cyanin. 1 to 1,500 to 15 c. c. emulsion, even gave red action.

There are two ways to color the gelatine film with a suitable coloring
matter: by mixing the latter directly before filtering into the ready
made emulsion, to produce at once colored plates; or to bathe dry
emulsion plates for one to five minutes in a solution containing the
sensitizing coloring matter. The plates have previously to be soaked for
a few minutes, whereupon they are bathed in an aqueous alcoholic solution
(with eosine yellow shade and eosine blue shade, in a solution of 1 to
3,000; but with cyanin in a diluted solution of 1 to 5,000). A mixture of
1/10 cyanin and 9/10 eosine yellow shade (of above concentration) acts as
a very favorable sensitizer. Lohse recommended bathing of the gelatine
plates in a solution of 0.03 eosine and 10 c. c. ammonia in 100 parts of
water. He found that very diluted eosine solutions, 1 to 20,000, acted as
a yellow sensitizer.

After washing, the plates have to be rinsed and dried--colored plates, as
long as they remain moist, being less sensitive than dry ones, and very
seldom the reverse.

This bathing of the ready made plates may give good results, but pure and
faultless plates are very seldom obtained, wherefore the first mentioned
manner (direct addition of color to the emulsion) is to be preferred.

After the experiments made by me, eosine mixtures acted equally in the
yellow and blue shade; likewise mixtures of cyanin 1/10 and eosine yellow
shade 9/10 were the most favorable. The process with eosine underwent
first of all a thorough test, of which the following are the results.

The color, solution I made as follows:

I. 0.5 grm. eosine yellow shade in 750 c.c. alcohol (95 per cent.) is
dissolved under good shaking.

II. 0.5 grm. eosine blue shade is also dissolved in 750 c.c. alcohol.

(The emulsion preparation I do not repeat, supposing that everybody is
conversant with the same.)

To an emulsion after Monckhoven's method, I add, before filtering, above
eosine solutions to 1,000 c.c. emulsion, 15 c.c. each of yellow shade and
15 c.c. of blue shade eosine; mix with a glass stirring-rod, filter, and
begin the flowing of the plates. On the contrary, to an emulsion made
after Henderson's method, double the quantity of coloring matter can be
added before flowing, without reducing the sensitiveness perceptibly.

Cyanin and eosine mixtures I give in the following proportions;

III. 0.5 grm. cyanin (iodo-cyanin) dissolved in 1,000 c.c. alcohol under
good shaking.

(All coloring matter solutions have to be filtered.)

To 1,000 c.c. Monckhoven emulsion I give:

25 c.c. eosine solution, yellow shade (I.).

5 c.c. cyanine solution (III.).

With Henderson emulsion I increase to double the quantity.

Further experiments taught me that even if 60 to 80 c.c., and more, of
these coloring matter solutions were added, and the emulsion was left to
coagulate and then laid in alcohol for several days, after which it was
washed well, so that hardly any coloration could be observed, it showed,
when making a copy of an oil painting, that the color sensitiveness of
the emulsion was not reduced, and that it had rather increased in
relative sensitiveness.

Anyhow, I put every colored emulsion for eight days in alcohol, having
experienced that hereby, after washing, just a sufficient quantity of the
coloring matter will remain as is necessary for the color sensitiveness.

For the correctness of what I have said here, the following experiment
made by me will speak:

I mixed with an emulsion a quantity of coloring matter five times
increased, flowed a plate with same, which I then exposed, but obtained
no picture whatever.

The same emulsion I placed for fourteen days in alcohol, washed it well,
and flowed a plate again, which latter had not only the full color
sensitiveness, but almost equaled an ordinary emulsion plate in total

From this can be concluded that--as above said--by placing the emulsion
in alcohol, all superfluous coloring matter is removed from the same, and
that only the quantity necessary for the color sensitiveness remains

Further, it may be mentioned that it might be of advantage to add to all
emulsions eosine besides iodide of silver, because this will give to the
emulsion clearness and brilliancy besides color sensitiveness, and
produce fine lights.

Finally, I express the hope that these communications may be useful to
the practical photographer, and it is my intention to report also about
other coloring matters at some future time.--_H.D., in Anthony's

* * * * *


This apparatus consists of a box containing a camera, A, and a frame, C,
containing the desired number of plates, each held in a small frame of
black Bristol board. The camera contains a mirror, M, which pivots upon
an axis and is maneuvered by the extreme bottom, B. This mirror stops at
an angle of 45 deg., and sends the image coming from the objective to the
horizontal plate, D, at the upper part of the camera. The image thus
reflected is righted upon this plate.


As the objective is of short focus, every object situated beyond a
distance of three yards from the apparatus is in focus. In exceptional
cases, where the operator might be nearer the object to be photographed,
the focusing would be done by means of the rack of the objective. The
latter can also slide up and down, so that the apparatus need not be
inclined when buildings or high trees are being photographed. The door,
E, performs the _role_ of a shade. When the apparatus has been fixed upon
its tripod and properly directed, all the operator has to do is to close
the door, P, and raise the mirror, M, by turning the button, B, and then
expose the plate. The sensitized plates are introduced into the apparatus
through the door, I, and are always brought automatically to the focus of
the objective through the pressure of the springs, R. The shutter of the
frame, B, opens through a hook, H, with in the pocket, N. After exposure,
each plate is lifted by means of the extractor, K, into the pocket,
whence it is taken by hand and introduced through a slit, S, behind the
springs, R, and the other plates that the frame contains. All these
operations are performed in the interior of the pocket, N, through the
impermeable, triple fabric of which no light can enter.

An automatic marker shows the number of plates exposed. When the
operations are finished, the objective is put back in the interior of the
camera, the doors, P and E, are closed, and the pocket is rolled up. The
apparatus is thus hermetically closed, and, containing all the
accessories, forms one of the most practical of systems for the itinerant
photographer.--_La Nature._

* * * * *


In our SUPPLEMENT No. 529 we gave an abstract of Prof. Dewars recent
series of lectures on the above subject at the Royal Institution. We now
present an abstract of the last and concluding lecture.


After the conclusion of his last lecture, Prof. Dewar distributed among
the younger listeners small pieces of a portion of the Dhurmsala
meteorite, which had been broken up for presentation to them by Mr. J.R.
Gregory, whose collection of rare minerals was recently to some extent
described in these pages. The lecturer stated that Sir F. Abel had given
him a large piece of a large meteorite, because he thought that the
speaker's piece ought to be bigger than theirs.

Professor Dewar also presented the listeners with a printed detailed
account of the fall of the Dhurmsala meteorite, including the report of
the occurrence sent to the Punjaub Government, and dated July 28, 1860.
The following are the main facts:

"On the afternoon of Saturday, the 14th of July, 1860, between the hours
of 2 and 2:30 P.M., the station of Dhurmsala was startled by a terrific
bursting noise, which was supposed at first to proceed from a succession
of loud blastings or from the explosion of a mine in the upper part of
the station; others, imagining it to be an earthquake or very large
landslip, rushed from their houses in the firm belief that they must fall
upon them. It soon became apparent that this was not the case. The first
report, which was far louder in its discharge than any volley of
artillery, was quickly followed by another and another, to the number of
fourteen or sixteen. Most of the latter reports grew gradually less and
less loud. These were probably but the reverberations of the former, not
among the hills, but among the clouds, just as is the case with thunder.
It was difficult to say which were the reports and which the echoes.
There could certainly not have been fewer than four or five actual
reports. During the time that the sound lasted the ground trembled and
shook convulsively. From the different accounts of three eyewitnesses
there appears to have been observed a flame of fire, described as about 2
ft. in depth and 9 ft. in length, darting in an oblique direction above
the station after the first explosion had taken place. The stones as they
fell buried themselves from 1 ft. to 11/2 ft. in the ground, sending up a
cloud of dust in all directions. Most providentially, no loss of life or
property has occurred. Some coolies, passing by where one fell, ran to
the spot to pick up the pieces; before they had held them in their hands
half a minute they had to drop them, owing to the intensity of the cold,
which benumbed their fingers. This, considering the fact that they were
apparently but a moment before in a state of ignition, is very
remarkable. Each stone that fell bore unmistakable marks of partial

Several meteors were seen at Dhurmsala on the evening of the same day.

Dr. C.T. Jackson analyzed a portion of one meteorite weighing 41/2 oz.; the
piece was 21/2 in. long, 11/4 in. wide, and 1 in. in average thickness. In
the course of his report he stated: "Its specific gravity is 3.456 at 68
deg. Fahr., barom. 29.9. Its structure is imperfectly granular, but not
crystallized, and there are small black specks of the size of a pin's
head, and smaller, of malleable meteoric iron, which are readily removed
from the crushed stone by the magnet. The color of the mass is ash gray.
A portion of the surface is black and is scarified by fusion. Its
hardness is not superior to that of olivine or massive chrysolite.
Chemical analysis shows that its composition is that of a ferruginous
olivine. One gramme of the stone, crushed in an agate mortar, and acted
on by a magnet, yielded 0.43 gramme of meteoric iron, which was
malleable. After the removal of this a qualitative analysis was made of
the residual powder. Another gramme was also taken, without picking out
the metallic iron, and was tested for chlorine and for phosphoric acid.
The results of the qualitative analysis were that the stone contains
silica, magnesia, a little alumina, oxide of iron and nickel, a little
tin, an alloy of iron and nickel, phosphoric acid, and a trace of
chlorine. These ingredients being determined, the plan for a quantitative
analysis was laid out, and was duly executed by the usual and approved
methods The following are the results of this analysis, per centum:

Silica, with traces of tin 40.000
Magnesia 26.600
Peroxide of iron 27.700
Metallic iron 3.500
Metallic nickel 0.800
Alumina 0.400
Chlorine 0.049
Phosphoric acid not weighed --

Messrs. Dewar and Ansdell analyzed the gases in the meteorite, of which
it contained three times its volume; the gases were in the following
proportions to each other:

Carbonic acid 61.29
Carbonic oxide 7.52
Hydrogen 30.96
Nitrogen 0.23

* * * * *


[Footnote: By David P. Todd, M.A., from the _Proceedings_ of the
American Academy of Arts and Science.]

In the twentieth volume of the _American Journal of Science_, at page
225, I gave a preliminary account of my search, theoretic and practical,
for the trans-Neptunian planet. I say _the_ trans-Neptunian planet,
because I regard the evidence of its existence as well-founded, and
further because, since the time when I was engaged upon this search,
nothing has in the least weakened my entire conviction as to its
existence in about that part of the sky assigned; while, as is well
known, the independent researches in cometary perturbations by Prof.
Forbes conducted him to a result identical with my own--a coincidence not
to be lightly set aside as pure accident.

That five years have elapsed since this coincidence was remarked, and the
planet is still unfound, is not sufficient assurance to me that its
existence is merely fanciful. In so far as I am informed, this spot of
the sky has received very little scrutiny with telescopes competent to
such a search; and most observers finding nothing would, I suspect,
prefer not to announce their ineffective search.

The time has now come when this search can be profitably undertaken by
any observer having the rare combination of time, enthusiasm, and the
necessary appliances. Strongly marked developments in astronomical
photography have been effected since this optical search was conducted;
and the capacity of the modern dry-plate for the registry of the light of
very faint stars makes the application of this method the shortest and
surest way of detecting any such object. Nor is this purely an opinion of
my own. But the required apparatus would be costly; and the instrument,
together with the services of an astronomer and a photographer, would,
for the time being, be necessarily devoted exclusively to the work.
While, however, the photographic search might have to be ended with a
negative result, in so far as the trans-Neptunian planet is concerned,
there would still remain the series of photographic maps of the region
explored, and these would be of incalculable service in the astronomy of
the future.

In the latter part of the paper alluded to above, I stated the
speculative basis upon which I restricted the stellar region to be
examined; also the fact that between November of 1877 and March of 1878 I
was engaged in a telescopic scrutiny of this region, employing the
twenty-six inch refractor of the Naval Observatory. For the purposes
contemplated I had no hesitation in adopting the method of search whereby
I expected to detect the planet by the contrast of its disk and light
with the appearance of an average star of about the thirteenth magnitude.
A power of 600 diameters was often employed, but the field of view of
this eye-piece was so restricted that a power of 400 diameters had to be
used most of the time. I say, too, that, "after the first few nights, I
was surprised at the readiness with which my eye detected any variation
from the average appearance of a star of a given faint magnitude; as a
consequence whereof my observing book contains a large stock of memoranda
of suspected objects. My general plan with these was to observe with a
sufficient degree of accuracy the position of all suspected objects. On
the succeeding night of observation they were re-observed; and, at an
interval of several weeks thereafter, the observation was again
verified." Subjoined to the original observations are printed these
verifications in heavy-faced type.

In conducting the search, the plans were several times varied in slight
detail, generally because experience with the work enabled me to make
improvements in method. Usually, I prepared every few days a new zone
chart of the region over which I was about to search; and these charts
while containing memoranda of all the instrumental data which could be
prepared beforehand, were likewise so adjusted with reference to the
opposition-time of the planet as to avoid, if possible, its stationary
point. The same thing, too, was kept in mind in selecting the times of
subsequent observation. Notwithstanding this precaution, however, it
would be well if some observer who has a large telescope should now
re-examine the positions of these objects.

Researches in faint nebulae and nebulous stars appearing likely to
constitute a separate and interesting branch of the astronomy of the
future, it has seemed to me that the astronomers engaged in this work may
like to make a careful examination of some of the stars entered in my
observing book under the category of "suspected objects." The method I
adopted of insuring re-observation of these objects was by the
determination, not of their absolute, but only of their relative,
positions, through the agency of the larger "finder" of the great
telescope. This has an aperture of five inches, a power of thirty
diameters, and a field of view of seventy-eight minutes of arc. Two
diagrams were usually drawn in the book for each of these objects, the
one showing the relation of adjacent objects in the great telescope, and
the other the configuration of the more conspicuous objects in the field
of view of the finder. Adjacent to these "finder" diagrams are the
settings--to the nearest minute of arc in declination, and of time in
right ascension--as read from the large finding-circles, divided in black
and white. The field of view of the finder is crossed by two pairs of
hairlines, making a square of about twelve minutes on a side by their
intersection at the center. The diagrams in all cases represent the
objects as seen with an inverting eye-piece. As the adjustment of the
finder was occasionally verified, as well as the readings of the large
circles, there should be no trouble in identifying any of these objects,
notwithstanding the fact that no estimates of absolute magnitude were
recorded. The relative magnitudes, while intended to be only approximate,
are still shown with sufficient accuracy for the purpose of the research,
and the diagrams are, in general, faithful tracings from the original

[Mr. Todd transcribes the observing book entire.]

* * * * *



The inestimable value of speech-reading and the practicability of its
acquisition under favorable conditions is a matter of common experience
and observation but justice to the deaf requires a recognition of the
fact that speech-reading has its limitations. Certain English words,
chiefly short ones, are practically alike to the speech-reader and the
context may fail sometimes to give a clew. It is necessary, at times, in
communicating with even expert speech-readers, to have recourse to
writing or oral spelling to convey the names of persons, places,
technical terms, etc., not in common use. Moreover, it is convenient to
have accurate and rapid means of conversation under unfavorable
conditions as to light and distance, or when from any cause the deaf
person's voice cannot be heard.

Writing is slow, inconvenient, and often impossible. Writing upon the
palm of the hand was proposed by the Abbe Deschamps in 1778, as utilizing
the sense of touch, and was used in darkness by him as a substitute for
speech, but it is neither accurate nor rapid. Writing in the air[1] with
the finger is also slow and uncertain, while the action is unpleasantly

[Footnote 1: The brilliant but wily Sicard, whose "show" pupils were
accustomed to honoring drafts at sight in appropriate responses to all
sorts of questions, acting upon the motto, _Mundus vult decipi, ergo
decipiatur_, schooled certain pupils in deciphering writing in the air,
and was thus prepared, in emergencies at his public exhibitions, to
convey intimations of the answers, while supposed to be using "signs" in
putting questions.]

Finger-spelling would appear to be a far more convenient, easy, rapid,
and accurate adjunct to speech or substitute for it than writing.

It is a common error to consider the ordinary manual alphabets as
deaf-mute alphabets and finger-spelling as the sign-language of the deaf.
Finger-spelling is to the deaf a borrowed art. It is used by many of the
educated deaf and their friends as a substitute for the sign-language,
and it enables them also to supply the deficiencies of the sign-language
by incorporating words from written language. Scagliotti, of Turin,
devised a system of initial signs[2] which begin with letters of the
manual alphabet, and Dr. Isaac Lewis Peet, of New York, has made a
similar application of manual letters to signs to suggest words of our
written language to the initiated deaf. But it should not be forgotten
that practice in finger-spelling is practice in our language.

[Footnote 2: _Quatrieme Circulaire_, Paris, 1836, p. 16. Carton's
_Memoire_, 1845, p. 73.]

The origin of finger-spelling is not known. Barrois, a distinguished
orientalist, in his _Dactylologie et Langage primitif_[3], ingeniously
traces evidences of finger-spelling, from the Assyrian antiquities down
to the fifteenth century upon monuments of art.

[Footnote 3: Barrois: _Dactylologie et langage primitif_, Paris, 1850,
Firmin Didot freres.]

The ancient Egyptians, Greeks, and Romans were familiar with manual
arithmetic and finger-numeration, as quaint John Bulwer shows by numerous
citations in his _Chironomia_ (1644). The earliest finger-alphabets
extant appear to have been based upon finger-signs for numbers, as, for
instance, that given by the Venerable Bede (672-735) in his _De Loguela
per Gestum Digitorum sive Indigitatione_, figured in the Ratisbon edition
of 1532.[4] Monks and others who had special reason to prize secret and
silent modes of communication, beyond doubt invented and used many forms
of finger alphabets as well as systems of manual signs.[5] The oldest
plates in the library of the National Deaf Mute College are found in the
_Thesaurus Artificiosae Memoriae_ of frater Cosmas P. Rossellius of
Florence, printed in 1579, which gives three forms of one-hand alphabets.
Bonet's work[6] of 1620 gives one form of the one hand Spanish manual
alphabet, which contains forms identical with certain letters in the
alphabets of 1579. This was introduced into France by Pereire and taught
to the Abbe de l'Epee by Saboureux de Fontenay, the gifted pupil of
Pereire. The good Abbe however continued to use a French[7] two-hand
alphabet which, he had learned when a child and which he said all
school-children knew. He mentions also a Spanish alphabet in part
requiring both hands, and remarks that different nations have different
manual alphabets. The Abbe Deschamps, a rival of De l'Epee, made use of a
finger alphabet in teaching the deaf to speak, which was not adapted to
rapid use. John Bulwer, in his _Chirologia, or the Naturall Language of
the Hand_, printed in 1644, figures five manual alphabets for secret

[Footnote 4: The library of the New York Institution contains a copy of
this very rare edition, bearing the title _Abacus atque velustissima
Latinorum per digitos manusque numerandi (quinetiam loquendi)
consuetudo_, etc., Ratisbonae, 1532.]

[Footnote 5: For an exhaustive account of the gesture speech in
Anglo-Saxon monasteries and of the Cistercian monks, who were
under rigid vows of silence, see F. Kluge: _Zur Geschichte der
Zeichensprache.--Angelsachsische indicia Monaslerialia,_ in
_International Zeitschrift fur Allgemeine Sprachwissenschaft,_ II. Band,
I. Halfte. Leipzig, 1885.]

[Footnote 6: _Reduccion de lasletras y arte para ensenar a hablar los
mudos_, 1620. The writer is under obligations to Sr. Santos M. Robledo,
of the Ministry of Public Works and Education, for advance sheets of the
reprint in beautiful facsimile of this rare work ordered by the Spanish
Government in 1881.]

[Footnote 7: The Abbe de l'Epee did not master the Spanish alphabet,
and, attaching but little importance to manual spelling, he was unsparing
in his criticism of _Messieurs the dactylologists_, but by "the irony of
fate" this alphabet occupies a face of the pedestal of one statue to his
memory, and in another statue the good Abbe is represented either as
receiving this alphabet from the skies or as devoutly using it.]

The first alphabet which appears to have been devised expressly for use
in teaching the deaf is that of George Dalgarno, of Aberdeen (1626-1687),
given in his remarkable philosophical treatise, _Didascalocophus, or the
Deaf and Dumb Man's Tutor_, Oxford, 1680. A facsimile of this alphabet is
given in the _Annals_, vol. ix., page 19. Words are spelled by touching
with your finger the positions indicated, either upon your hand or upon
the hand of your interlocutor. An alphabet of the same character,
however, was not unknown at an earlier date. For Bulwer, in 1648, says:
"A pregnant example of the officious nature of the Touch in supplying the
defect or temporall incapacity of the other senses we have in one Master
_Babington_ of _Burntwood_ in the County of _Essex_, an ingenious
gentleman, who through some sicknesse becoming _deaf_, doth
notwithstanding feele words, and as if he had an eye in his finger, sees
signes in the darke; whose Wife discourseth very perfectly with him by a
strange way of Arthrologie or Alphabet contrived on the joynts of his
Fingers; who taking him by the hand in the night, can so discourse with
him very exactly; for he feeling the joynts which she toucheth for
letters, by them collected into words, very readily conceives what shee
would suggest unto him. By which examples [referring to this case and to
that of an abbot who became _deaf, dumb_, and _blind_, who understood
writing traced upon his naked arm] you may see how ready upon any
invitation of Art, the _Tact_ is, to supply the defect, and to officiate
for any or all of the other senses, as being the most faithfull sense to
man, being both the _Founder_, and _Vicar generall_ to all the rest."[8]

[Footnote 8: _Philocophus_: or, THE DEAFE and Dumbe Mans Friend. By I.B.
[John Bulwer] sirnamed the _Chorosopher_. London, 1648. Pp. 106,107.]

Dr. Alexander Graham Bell has modified the Dalgarno alphabet, and has
made considerable use of it in its modified form as figured in the
_Annals_, vol. xxviii., page 133. He esteems it highly for certain
purposes, especially as employing touch to assist the sight or to release
the sight for other employment, as in reading speech for instance. Here a
touch-alphabet may be an efficient aid to the sight, as the touch may
fairly keep pace with the rapidity of oral expression in deliberate
speech. An objection of Dr. Kitto to the two-hand alphabet so widely know
by school-children and others in Great Britain and in this country would
seem to apply with greater force to the Dalgarno alphabet: "To hit the
right digit on all occasions is by far the most difficult point to learn
in the use of the [two-hand] manual alphabet, and it is hard to be sure
which fingers have been touched."[9]

[Footnote 9: Dr. Kitto remaks the following common mistakes in reading
rapid two-hand spelling: the confounding _i_ with _e_ or _o_; _d_ with
_p_; _l_ with _t_; _f_ with _x_; _r_ with _t_ and with one form of _j_;
_n_ with _v_, and adds: "Upon the whole, the system is very defective,
and is capable of great improvement." _--The Lost Senses_, p. 107.]

It is not the purpose of the writer to attempt even a catalogue of the
numerous finger alphabets, common, tactile, phonetic, "phonomimic,"
"phonodactylologic," and syllabic, which have been proposed for the
special use of the deaf.

The one-hand alphabet used by Ponce and figured by Bonet was common in
Spanish almanacs hawked by ballad-mongers upon the streets of Madrid in
the days of De l'Epee, and although rejected by him, it was adopted by
his pupils. This with slight modifications became the French manual
alphabet which was introduced at Hartford by Dr. Thomas Hopkins
Gallaudet. This alphabet is known in almost every hamlet in the land.
Slight changes in the form of certain letters, or in the position of the
hand, in the direction of greater perspicuity and capacity for rapid use,
have taken place gradually, though there is no absolute uniformity of
usage among instructors or pupils.

This "American" alphabet, as here presented, through the liberality of
Dr. A. Graham Bell, has been drawn and engraved from photographs, and
represents typical positions of the fingers, hand and fore-arm from a
uniform point of view in front of the person spelling, or as seen in a
large mirror by the user himself.[10]

[Footnote 10: See an interesting paper on figured manual alphabets by
H.H. Hollister, _Annals_, xv., 88-93.]

This alphabet can be learned in less than an hour, and many have learned
it by extraordinary application in ten minutes. It is recommended that
the arm be held in an easy position near the body, with the fore-arm as
in the plates. Each letter should be mastered before leaving it. Speed
will come with use; it should not be attempted nor permitted until the
forms of the letters and the appropriate positions of the hand are
thoroughly familiar. The forms as given are legible from the distant
parts of a public hall. In colloquial use the fingers need not be so
closely held nor firmly flexed, as represented, but sprawling should be
avoided. It is not necessary to move the arm, but a slight leverage at
the elbow is conducive to ease and is permissible, provided the hand
delivers the letters steadily within an imaginary immovable ring of, say,
ten inches in diameter.


This adjunct to speech-reading is recommended for its convenience,
clearness, rapidity, and ease in colloquial use, as well as for its value
as an educational instrument in impressing words, phrases, and sentences
in their spelled form upon the mind, in testing the comprehension of
children, and in affording by easy steps a substitute for the

In the simultaneous instruction of large classes not able to follow
speech, finger-spelling "may take the place of signs to a great extent in
the definition, explanation, and illustration of single words and
phrases, and in questions and answers upon the lessons, and in
communications of every kind to which the stock of language already
acquired may be adequate."[11]

[Footnote 11: _The Use of the Manual Alphabet_, by S. Porter: Proceedings
of the Eighth Convention of American Instructors, pp. 21-30. Copies of
the Proceedings which contain this extremely valuable paper may be
obtained of R. Mathison, Superintendent of the Ontario Institution,
Belleville, Ontario.]

All who have anything to do with the school instruction of the deaf may
well bear in mind the matured opinion and wise counsel of Professor
Samuel Porter, of the National College, the Nestor of American
instructors. In this connection, Professor Porter says:

_In short, let the gestural signs come in only as a last resort, or, so
far as possible, merely as supplementary to words, re-enforcing them in
some instances, or employed as a test of the pupil's knowledge of words,
but always, so far as possible, falling behind and taking a subordinate
place. And let the pupils be required, in what they have to say to their
teachers in the schoolroom or elsewhere, to employ the finger-alphabet
instead of natural signs to the utmost possible extent, and this by
complete sentences and not in a fragmentary way_.


_Professor in the National College, Washington, D.C._.

* * * * *


The use of natural flowers for decorating the person is instinctive among
certain peoples, and a question of fashion among others. It is in
Oceanica especially that this taste seems to be nationally developed, and
from the narrative of Cook we know that the Tahitian belles use in their
toilet the perfumed flowers of the pua and tiare (_Carissa grandis_ and
_Gardenia Tahitensis_), whose dazzling whiteness renders still more
marked the ebony blackness of their wealth of hair.

In Europe this custom is traditional in many countries. Women of fashion
scarcely ever appear at a soiree or ball without wearing a camellia or an
exotic orchid on their breast or in their head-dress, and so, too,
gentlemen of "high life" do not go out without a boutonniere of white
violets or Cape jasmine.

But natural flowers, being ephemeral, were once replaced in the toilets
of ladies by artificial ones. The artificial flower industry originated
in China, and from thence passed into Italy and afterward into France. In
course of time people got tired of artificial flowers for decorative
purposes, and then imitation fruits made their appearance, and were worn
in the toilets of dowagers and mothers of families.

Now that fashion, that tyrant born of dressmakers, milliners, and tailors
of renown, obliges us to clothe ourselves according to accepted models,
the kaleidoscope no longer suffices to find the most varied designs and
most fantastic cuts for garbs or ornament.

In recent years pleasing objects have been borrowed from the animal
kingdom, such as small birds and quadrupeds, and insects with brilliant
colors and of strange forms. What formerly would have been a repulsive
object (such as a great longicorn or beetle) is worn with ease by the
belles of our time. The use of such objects of natural history, however,
has been about confined to the decoration of head-dresses or the
manufacture of jewelry.

of _Casuarina_ and fruit of alder. 2. Acorn cup, involcure of beech, and
pod of medick. 3. Fruit of _Eucalyptus_, cups of acorns, Job's tears, and
cones of cypress.]

As the need of creating new models is always making itself felt, one
ingenious manufacturer, Mr. Collin, has turned toward the vegetable
kingdom, and brought out an elegant and original style of dress-trimming
made of certain indigenous and exotic fruits and seeds that no one would
ever have thought of using for such a purpose. Instead of pendants made
of wood and covered with silk or velvet, Mr. Collin uses dry fruits or
seeds, which he has previously dyed, gilded, or silvered.

[Illustration: FIG. 2.--DRESS TRIMMINGS OF FRUITS AND SEEDS. 4 and 5.
Fruit of alder. 6. Fruit of _Casuarina_. 7. Fruit of _Arbutus_. 8. Fruit
of _Casuarina_.]

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