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evidence then agreed in that opini
then that idea has been gaining gond
appears to be now a fixed principle
dynamics; for Mr. Varley, in t
paper read before the Royal Instit. A
that "while light and sound have
velocity, electricity has not." Wel
velocity at all it must have a definit
Certainly all velocities vary accorti
cumstances, but that does not
definity; therefore we may con
electricity has no velocity, that is,
taneous: this, of course, if we are t
our conclusions by authority, for gra
rities than these we cannot have a d
sent. From this point of view
with propriety speak of an electre
nor of charging or discharging a cent
in fact, there can be no conductor, fra
implies a motion, and there can be see
where no time is occupied-ins
being the negation of time.

We must confess that we feel su
puzzled to find language in which
this matter; for all the language wh
sents itself to us contains time, spac
velocity, or somehow implies one or c
all of these: that is, perhaps, our irim:
At any rate, we find it difficult to avai
ing that which is now held to be p
The effect at the other end of a―
ductor, that is an assumption which
a contradiction: try medium-but tha
the middle term between two extreme
involves progression, consequently us!
rejected:-well, then, let us not say wha
but simply the effect at the other e
instantaneous. And that is what ha
Thomson did say, and we are sorry thr
not give us the abstract name of f
which had two ends and a mid,
should not contradict that instantaneit
cause and effect. Cause and effect!
cause and its effect are successive,
simultaneous; therefore they are inc
with our subject. What is this su
If it be anything, it must be either
an effect. If a cause it is still the
some prior cause, for science cannot in
final causes; in fact, it must be both-ta
the effect of somewhat that preceded
I cause of somewhat that always succes
we cannot reach finality either prir
terior.

JUNE 28, 1867.

great errors. Undoubtedly the velocity of microscopes by different persons. A very care
electricity is very great, but there are reasons ful series of observations was made, expressly to
All
for doubting that it is as great as that of light determine this point; care being taken to ad-
-of which this is one-the electric force is more just the eyepieces accurately to focus.
local in its action than that of light, conse- appearance of personal equation then vanished.
quently, more external; therefore, less subtle I think that these experiments throw great light
on the origin of supposed personal equations
and less active. Magnetism lies nearer to
light than electricity in universality and sub-where there is no movement of the object ob-
served.
tlety, but electricity is external to magnetism;
Attention has been given to the compensation
electricity requiring a special medium, but of the chronograph barrel clock pendulum, and
magnetism is exerted through a medium as its rate is now very steady. It is known to the
general at least as that of light. But the velo-Visitors that the one-second punctures on the
city of light is perfectly definite, and certainly barrel-sheet follow each other on a spiral whose
also is that of electricity, but being more inert interval of coils is one-tenth of an inch; and
it experiences much more interference, and that, for easily reading these, an impressed
It would spiral line is necessary. Hitherto, the spiral line
especially by the magnetic sphere.
be well if the relation between electricity and has been traced by ink flowing from a glass
magnetism were clearly traced out; it would pipette. The difficulty, however, of procuring
solve many difficulties, and notably that of in- pipettes suitable to our wants has induced us to
employ the continuous indenture produced by a
duction, about which very much has been said, steel point. It requires the application of greater
but very little understood, though we are force for turning the barrel under it, but in other
The motor
sorry to find that there is as much dogmatism respects it is very satisfactory.
about that as there is about other branches of clock is in good order. This clock is kept to
mean solar time with all the accuracy that we
the electric science.
can give to it, by application at pleasure of mag-
netic or galvanic attraction or repulsion on a
magnet fixed to its pendulum. It is used to
maintain several clocks in the Observatory to
accurate mean solar time, and to distribute

THE ROYAL OBSERVATORY,

GREENWICH.

Stars observed

possible day of observation.
with the transit circle are:-Clock-error-stars,
as far as they are visible to us; azimuth stars,
to the number of 118; nautical almanac stars,
among which we may with advantage sometimes
include stars of the Redhill catalogue; stars
culminating with the moon, or occulted by the
logues; completion of the re-observation of
moon: completions of our own published cata-
Bradley's catalogue (of the whole number, about
1,211, the number wholly observed is 1,065, and
the number partially observed 1,159); stars used
in the British, American, and Indian surveys;
stars useful for refraction theories; proper motio n
stars (including Sirius); variable stars; Arge-
lander's special list of stars.

The equatoreals have been used principally as
instruments for observations of phenomena not
Drawings of Saturn
requiring circle measurement, and for inspection
exhibit no trace of that supposed difference
of special appearances.
between the outline of the ball and the outline
of the ball's shadow on the ring, which has been
ascribed to the curvature of the ring's surface.
Drawings of the spot Linnæus on the moon leave
no doubt that it is still a vory shallow cup.
Complete preparations were made for an elabo-
rate system of instrumental measures during the
solar eclipse of 1867, March 5 (somewhat similar
to those made successfully during the solar
eclipse of 1860), by which the errors of the tabu-
been determined. The bad weather prevented
Eight occul-
semi-diameters of the sun and moon would have
tations of stars by the moon have been observed
the carrying out of this intention.
(four disappearances and four reappearances),
and seventeen phenomena of Jupiter's satellites.
The end of the solar eclipse of 1866, October 8,
and the beginning of that of 1867, March 5, were
observed.

WE have been favoured with a copy of the seconds, galvanic currents and hourly galvanic lar elements of the moon's place, and the tabular

thence to

report of the Astronomer Royal to the Board of Visitors of the Royal Observatory, Greenwich, read at the annual visitation of the Royal Observatory, June 1, 1867, and from which we make the following interesting extracts:-Referring first to the telegraphic system of the esta. blishment we find that the eight telegraph wires are now led (by arrangement with the Electric and International Telegraph Company) under. ground to the Greenwich railway station, and the poles of the South-Eastern railway, and by a cable under Deptford Creek. At Deptford station, by the liberal permission of the South-Eastern Company, a turnplate is fixed, into which two of the wires are led; and from the Admiralty wire which passes through the High-street of Deptford, a loop is led into the same turnplate, so that the Admiralty loop can practically be extended into the Royal Observatory, and can, when necessary, be interrupted there. The Astronomer Royal states that he has been desirous of maintaining this command of wire with the hope that he may yet have occasion to use it for the transmission of signals to Devonport in reference to the exhibition of time signals on the Start Point, or in other directions for similar purposes.

We are in a dilemma; either our elem are wrong, or else we are not right But there is no mistaking it, they do cause and effect are simultaneous m the logicians. Mr. Preece lately said a wire to the moon and a message cond there instantaneously. It is of no cons that the expression used contradict assertion it was intended to co Preece meant to say that he could te the moon in no time, and may be " too." We wonder that such expressin never suggested to our electricians were removing electricity out of the g physics altogether. What more can y of thought? All material things, stand them, exist in time and space, mutation of matter requires time for its existence. Every material th have a length, a breadth, and a thick is, it must occupy space; and ey exerted in and through matter mast in and through like dimensions; and of such exertion of force is a velocity, a motion in a time, and a motion of position, relative or absolute; ther exertion of every material force is th in time; consequently, not ins Instantaneity is a point in time beginning or ending of a time, a 3 m

matical point is a point in beginning or ending of a line mutation of matter is a succession

It is clear, therefore, that electric more than the action of any other for exerted through space without sme fit as though it en

The proposed line of railway through the
town of Greenwich and on the north side of the
Hospital Schools, promoted by the South-Eastern
Railway Company, which was considered unob-
jectionable in reference to the interests of the
Observatory, received the entire sauction of the
legislature in the summer of 1866. But no action
is yet taken on it, and no immediate action is
contemplated. The London, Chatham, and
Dover Company have made no new application
for sanction of their line of junction with the
South-Eastern Company's line (rejected last year
on a point of standing orders). It seems not
impossible, says the report, that in a few years
we may have to fight the whole battle over again.
With respect to the astronomical instruments,
the Astronomer Royal observes :-I alluded in
my last report to the probability of finding the
astronomical flexure of the telescope, after cutting
away small portions of the central cube, sensibly
changed. Cast iron, apparently, is always in a
state of constraint, and the removal of a strained
part usually alters the form and stiffness of all
that is left. Very lately a most careful set of
observations has been taken by Mr. Dunkin for
determining the astronomical flexure with the
help of the new collimating reversed telescopes;
and the co-efficient for southern objects, which
formerly was+0"-76, is now-0":34. [This is
confirmed by another series of observations.]
The difference of flexures of the two ends has,
therefore, been altered more than a second of arc.
I have no information on the state of the absolute
flexure. The plan of stretching the horizontal
wire in the field of view has proved unsuccessful;
the wire soon broke, apparently from dampness
of atmosphere.

currents (the latter through England); and also
to change connections of wires which enable us
to receive signals from distant clocks and time
balls.

The south-east equatoreal is in excellent order.
No alteration has been made in the telescope,
except by the introduction of a solar eyepiece,
with a green glass in front of the field glass.
A direct-view spectroscope, the property of Mr.
Stone (first assistant), has sometimes been used
with it. The chronometer carried at the eye
end of the telescope, and adjusted by galvanic
regulating action to exact sympathy with the
transit clock is perfectly successful. To give
audible indications of the seconds' currents, oue
of the old galvanic chronometers is used. The
water-clock, which gives motion to the equa-
toreial, is driven by the force of water from the
ordinary supply pipes acting through a turbine,
the opening of the last tap being determined by
Siemen's chronometric governor. The mean
velocity of the clock, as I believe, does not
depend upon the openings of the preceding taps,
but the rapid inequalities of velocity do depend
on them in a way which it is very difficult to
A tap has now been
explain from theory.
established in the immediate vicinity of the
water-clock, and by experiments on this we have
acquired complete mastery of the instrument.
It can now be made to move uniformly, without
any sensible inequality, and with astronomical
accuracy.

The new portable altazimuth by Mr. Simms
has been tested by observations for the latitude,
and found to be sensibly perfect. I may mention
that a study of defects in the vertical circle of
a small altazimuth formerly used by me, and
an inspection of the operations in the instrument
maker's workshop have convinced me that the
principal error to be feared in instruments of this
class is ovality of the graduated limb; this
cannot be eliminated by two microscopes, and
never be fitted
such an instrument should
with two only. Our instrument has four. The
portable transit by Mr. Brauer was received in
the summer, and appears to be everything that
could be desired. I had fully expected that em-
ployment would have been found for both these
instruments in determination of a fundamental
American longitude, but the necessity has been
removed, as I shall explain in a subsequent sec-
tion.

Turning to the astronomical observations we find Professor Airy stating that long ago, it has been indicated by continental writers that the best employment for a principal established observatory is the determination of fundamental places of important stars, and fundamental elements of the motions of the earth, moon, and planets. From the foundation of the Greenwich Observatory these objects have been kept steadily in view, and as much so in the last as in preced. ing years. In particular, the moon has received that extraordinary attention which has been Some results of observation had given rise to given to her at all times in our history, but more the idea that there is really a personal equation particularly in the last twenty years, when two in the determination of the runs of micrometer-instruments have been directed to her on every

The meteorological instruments, whether those read by eye for indications at the moment, those read for definite part registers, those which give continuous mechanical registers, or those which give continuous photographic registers, are all in good order. They include barometers, dry and wet thermometers, radiation thermometers, thermometers in the Thames, Osler's and Robinson's anemometers, Osler's and six other pluviometers. The photographic barometer has shown a tendency in its indications to "jump," indicative of some friction which I have not yet investigated. In Osler's anemometer a surface of two square feet it now exposed to the wind instead of one foot as formerly; and the plate is supported by weak vertical springs instead of rods running on rollers. Its indications are delicate This than formerly. much more change was made by Mr. Browning. With new pressure-plate of Osler's the the pressures per square foot regis meter tered in the last six months are larger than any that we have had before. Whether any part of this is due to the circumstances that the plate is larger and its motion easier, or whether it is wholly due to the great violence of the wind in this stormy season I am unable to say. With Robinson's anemometer there is connected a revolving barrel moved by clockwork to be covered each day by a sheet of paper, on which a pencil carried by the anemometer makes a trace, exhibiting continuously the speed of the wind and the aggregate of its motion.

anemo

With regard to magnetical and meteorological observations daily communication is made to M. le Verrier for his meteorological bulletin; and weekly communication to the Registrar-General for his sanitary report. November 14 were well observed. sand three hundred were registered. variations of frequency at different times were very well noted. The points of divergence were carefully determined.

The meteors on
Eight thou.

The

Under the head of chronometers, communications of time, determinations of longitude, the Astronomer Royal reports as follows:-On 1867, May 3, we have on hand 192 chronometers, thus classified :-95 box chronometers, 14 pocket chronometers, and 10 deck watches, the property of the Admiralty; 17 on trial for purchase to replace six bought by the Japanese authorities; 55 makers' chronometers on competitive trial. All chronometers, except those which have been in our hands so long that we have great familiarity with their rates, are compared every day with a clock which is sympathetic with the motor clock; those in the excepted case are compared once a week. All are subjected to

some weeks' trial in a temperature not exceeding THE 90 deg. Fah. All estimations of the value of chronometers to be purchased, and all superin. tendence of repairs rest with me. For issuing chronometers to the outports, a new system of packing has been introduced. It is found that

with reasonable attention the chronometers can

INSTITUTION OF HYDRONOMICAL with hydronomical and nautical science and art
AND NAUTICAL ENGINEERS.
for the examination of such inventions, and
for giving publicity to the same at a moderate

inserted at page 288 an inquiry as to cha N our impression for the 10th of May last we racter and objects of the Institution of Hydronomical and Nautical Engineers. The first in. be sent safely by railway to almost any distance. timation since our inquiry of the existence of this The motor clock, and the apparatus connected society has been the receipt by us of a pamphlet with it, are in good order. This clock is com-fore, glad to be able to give some particulars of embodying its proceedings. We are now, there pared and regulated by an easy practical pro the society. It appears that the Institution was cess. It maintains various clocks in sympathy established on July 4, 1866, with the following with itself; it regulates clocks in London, sends signals through Britain, drops the Deal time- objects :ball, fires guns at Newcastle and Shields (I think also at Sunderland), and puts communications in

such a state that we can receive automatic re

"

ports from the signal places, as we may desire. I may, however, specially mention that daily signals are now sent to some places in Ireland; and that, during the expedition of the " Great Eastern for laying down the Atlantic cable time signals were sent on board twice a day to enable her constantly to determine her longitude. A most important determination of longitude has been made. In the autumn of 1866, arrangements were made by me, with the view of determining the longitude of a primary point in Newfoundland, by galvanic currents through the Atlantic cable, in the spring of 1867. However, in October of 1866, the authorities of the United States Coast Survey determined to act, and my friend Dr. B. A. Gould, having made all necessary arrangements at Heart's Content, and on arriving in London having secured the friendly assistance of the directors of the Atlantic cable, proceeded to establish a transit instrument at Foilhommerum, in Valentia. Advantage was taken of this opportunity for determining the longitude of Foilhommerum from Greenwich. After overcoming various difficulties all operations were successful. I have been favoured by Colonel Sir H. James, superintendent of the Tri. gonometrical Survey, with the geodetic measure of difference of longitude between Foilhommerum and my first station Feagh Main; and I have the longitude of Feagh Main, found by different

methods, as follows. By chronometers in 1844,

41m. 23-238.; by galvanic communication with
Knights Town in 1862, 41m. 23-378.; by gal-
vanic communication with Foilhommerum in
1866, 41m. 23-19. Dr. Gould, immediately after
his return to America, determined the arc of
longitude from Heart's Content to Cambridge,
U.S. The collected results for longitude of Cam-
bridge from different sources are--By moon
culminators, Walker in 1851, 4h. 44m. 28428,
Newcomb in 1862-3, 4h. 44m. 29 568.
; by
eclipses, Walker in 1851, 4h. 44m. 29 64s.;
by occultalion of Pleiades, Pierce, 1838-1812,
4b. 44m. 39-91, 1856-1861, 4h. 44m. 30'90s.;
by chronometers, W. C. Bond in 1851, 4h. 44m.
30-669., G. P. Bond in 1855, 4h. 44m. 31.89s.;
by Atlantic cable, 1866, 4h. 44m. 30 99s.

THE

BREECH-LOADING RIFLES.

HE sub-committee on breech-loaders has concluded the first stage of the inquiry; and the result is, that nine systems have been selected for further trial. The fortunate competitors are Messrs. Albini and Braendlin, Mr. Remmington, Major Fosbery, Mr. Burton (two systems), Mr. Peabody, Mr. Martini, Mr. Joslyn, and Mr. Henry. We understand for the best of these arms, whether adopted for the service or not, £1,000 will be awarded, and for the arm which, while attaining a satisfactory degree of excellence in other particulars, is selected for merit in respect to its breech mechanism, £600 will be the prize. If the best arm appears to the committee to be worthy of adoption, it will be placed in competition with the Snider rifle, which it will be required to beat before its adoption is confirmed. If, on the other hand, none of the prize arms should in the opinion of the committee satisfy the service requirements, then the best of those arms which from failure to fulfil the conditions laid down are out of the prize competition will be selected on their merits to continue the contest. Each of the accepted com petitors will be required, within four months of his receiving the notice, to furnish for experiment at Woolwich six arms in strict conformity to the specimen arm submitted, with 1,000 rounds of ammunition per arm; and a sum of £300 will be paid to each such competitor to cover the expense of the six rifles and of the supply of ammunition.

cost.

Seventh. To advance the interests of authors

and inventors by granting permission (under proper regulations and restrictions) that any book, pamphlet, manuscript, model, chart, plan, drawing, instrument, or appliance which shall tution, or by the duly appointed referee or have been approved by a committee of the insti. referees thereof, may have such approval recorded thereon under the official stamp or seal

of the registrar of the institution.

Eighth. To afford a recognised and authoritative medium through which medals and premiums may be awarded for the encouragement of hydronomical and nautical science and art.

cussion of any matter or subject forming part of, Ninth. To afford facilities for the public dis or connected with, hydronomical and nautical science and art, and for the appointment of special committees in relation to any branch thereof.

First. To promote the acquisition of that species of knowledge and skill which is required for the right exercise of the profession of a hydronomical and nautical engineer, or, in other ing and applying the powers and materials in words, that which constitutes the art of directnature to the use, convenience, and defence of mankind in the pursuits of navigation, maritime commerce, submarine telegraphy, and naval and described as being exemplified in the several warfare; and which art may be further defined chemical, geological, mathematical, and meapplications of hydronomical, nautical, physical, chanical science to the determination of the laws which govern the constitution, specific gravity, salt water; to the determination of the causes temperature, and motion of fresh, brackish, and and motions of streams, tides, currents, and waves, and of the laws regulating the passage of bodies in and through water; to the construction, armament, and means of attack and defence tion, fitting, equipment, maintenance, locomoof sailing ships, steam, and other vessels; to the to the necessity for the further cultivation, con. Eleventh. To obtain a more general attention location, construction, adaptation, improvement, solidation, and advancement of hydronomical equipment, maintenance, conservancy, and and nautical science and art; and to procure the means of attack and defence of harbours of removal of any disadvantage of a public chabours, arsenals, naval and mercantile dockyards, or prospective development thereof. refuge, breakwaters, piers, commercial har-racter which may impede the present progress and of river navigation, docks, floating and of the institute is No. 8, Bury-court, St. Mary

graving docks, and also to the construction of
all appliances for the building and repair of
vessels, or for loading and discharging their
cargoes; to the sailing, conducting, navigating,

and to determina

and piloting of vessels, a to the preparation of
charts and sailing directions; to the determina-
tion of the regime and actual hydro-geological
state and condition of tidal and other harbours,
shores, estuaries, and rivers; to ascertaining the
taken place therein, and to predicating the pro-
extent and causes of changes which may have
bable effects of existing agencies, or of the execu-
to the location and construction of buoys,
tion of any proposed works connected therewith;
constructing all other edifices, engines, machines,
beacons, and lighthouses; and to making or
instruments, or appliances for the use, con
Venience, and safety of seamen.

classification, election, and registration, a reliable
Second. To establish, by a careful system of
register, of duly qualified hydronomical and
nautical engineers, of nautical experts, and of
other persons possessing hydronomical and
nautical science and experience.

Third. To afford facilities for the appointment
or selection of duly qualified assessors or referees
for the assistance of any court or tribunal, or for
making any inquiry, judicial or otherwise, in re-
lation to any matter requiring a competent
knowledge of hydronomical and nautical science
and art.

Tenth. To aid in the diffusion of sound inviously defined professional duties of a hydroformation on subjects connected with the prenomical and nautical engineer, by granting per. mission (under an agreement as to the copy. any book, pamphlet, manuscript, chart, plan, or right and expense of editing and printing) that drawing which shall have been approved by pro perly appointed referees may be printed and published among the published papers of the in stitution.

Axe.

The office

DEATH IN THE CISTERN. been made by Professor Hannon, of the NOME interesting investigations have recently University of Brussels, with regard to diseases produced by vegetable organisms. His researches have led to important discoveries, the professor having been able to prove that the spores of of their fructification, are capable of producing some species of fresh water algae, at the period intermittent fever. The observations and relead to the belief that many other diseases to searches of several eminent medical authorities origin in the vegetable organisms which abound which the human frame is liable have their in water. Some of the spores are probably

thrown off into the atmosphere, and, being drawn far the larger portion doubtless find their way into the lungs, are absorbed by the blood, but by into the stomach, and so give rise to disorders of the alimentary canal. Their tenacity is said to be so great, that the temperature of boiler water is insufficient to destroy their vitality, and even beer and bread, notwithstanding the heat to which they have been subjected, in many cases show abundant evidence of the existence of these algæ. These facts all point to the necessity, so frequently urged by us, of filtering the water used for manufacturing purposes as well as for domestic use. To meet this necessity, which becomes very special at the present period of the year, we would direct attention to a method of filtration which appears well adapted to meet the evil in question. This is embodied in the Main Service Filter, manufactured by the Sili cated Carbon Filter Company which can be adapted to the supply-pipe of any brewery dis tillery, or manufactory, and thus purify all the water before entering the building. The value of such a method of purification will be appre ciated by those who have ever seen the inside of a large cistern after having been used for some time without cleaning. The quantity of vege table matter which covers the sides of such a cistern is astonishing, and it cannot be a matter for wonder that disease is propagated by water kept in such a receptacle. Mere straining of water through animal charcoal is not sufficient to stop this vegetable matter, but the principle of the Silicated Carbon Filter is the employment of a porous slab cemented into a filtering vessel. This arrangement effectually prevents the passage of any extraneous substance, and the combina. Sixth. To afford facilities to inventors and tion forms a very efficient mechanical and che. other persons interested in inventions connected' nical water-purifier.

Fourth. To afford facilities to suitors, and to the promoters or opposers of any project, scheme, or undertaking, for procuring accurate, complete, and trustworthy information in relation to questions of hydronomical and nautical science and art, either by the discussion of a paper on the subject at a discussion meeting of the institution, or by the appointment of a referee or referees, or a committee of properly qualified persons; or, if necessary, by appointing a competent person or persons to be an inspector or inspectors, for the purpose of making a local survey or inspection in relation thereto, or otherwise.

Fifth. To afford facilities for the appointment or selection of hydronomical and nautical surveyors, draughtsmen, or other competent persons, for making, preparing, examining, and verifying measurements, levels, soundings, models, maps, plans, drawings, charts, specifications, statements, reports, and other documents in relation to hydronomical and nautical science and art.

Lwith hydronomical and nautical sticks

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for the examination of sch for giving publicity to the same

cost.

Seventh. To advance the interes
and inventors by granting
proper regulations and restric
book, pamphlet, manuscript, modei, ch
drawing, instrument, or appliance
have been approved by a commite
tation, or by the daly appointed se

s referees thereof, may have s corded thereon under the official y e of the registrar of the instituti

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Eighth. To afford a recognised andunter medium through which medisi a may be awarded for the co hydronomical and nautical science at

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of

Ninth. To afford facilities for the cussion of any matter or subject formi or connected with, hydronomical a escience and art, and for the appare special committees in relation to thereof.

Tenth. To aid in the diffusion of ,formation on subjects connected was viously defined professional duties dan Snomical and nautical engineer, by graci mission (under an agreement as t right and expense of editing and any book, pamphlet, manuscript, car a ddrawing which shall have been appre perly appointed referees may be pr published among the published papan t stitution.

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; searches of several eminent medical at ,, lead to the belief that many other Le or which the human frame is liste 8, origin in the vegetable organisms a- in water. Some of the spores are

thrown off into the atmosphere, and br of into the lungs, are absorbed by the bins, le far the larger portion doables find d into the stomach, and so give rise to fixe of the alimentary canal. Their teac d. be so great, that the temperature des is insufficient to destroy their rita it beer and bread, notwithstanding 5 es which they have been subjected, in my or show abundant evidence of the existens e- algæ. These facts all point to the at frequently urged by us, of fisering a ce used for manufacturing purposes & | domestic use. To meet this recess?

to becomes very special at the presen

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e, the year, we would direct attection a e, of filtration which appears well adage to the evil in question. This is embolic ce! Main Service Filter, manufactured a on cated Carbon Filter Company - adapted to the supply-pipe of say ortillery, or manufactory, and thus parts ed water before entering the building y

n- of such a method of purification or ciated by those who have ever see al' a large cistern after having been r-time without cleaning. The qua

table matter which covers the side nt cistern is astonishing, and it cannot ir-¡ for wonder that disease is prop r-kept in such a receptacle. Mer ad water through animal charcoal 12 rs, to stop this vegetable matter, but the a the Silicated Carbon Filter is the its a porous slab cemented into a ce This arrangement effectually prevents of any extraneous substance, and ndtion forms a very efficient mech ter-purifier.

JUNE 28, 1867.

THE MECHANICS' MAGAZINE.

ON THE OCCLUSION OF HYDROGEN GAS
BY METEORIC IRON.

BY THOMAS GRAHAM, F.R.S.
OME light may possibly be thrown upon the
history of such metals found in nature as
are of a soft colloid description, particularly na-
tive iron, platinum, and gold, by an investiga-
tion of the gases which they hold occluded, such
gases being borrowed from the atmosphere in
which the metallic masses last found themselves in
a state of ignition. The meteoric iron of Lenarto
appeared to be well adapted for a trial. This
well-known iron is free from any stoney admixture,
and is remarkably pure and malleable. It was
found by Wehrle to be of specific gravity 7'79,

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From a larger mass a strip of the Lenarto iron
50 millimetres by 13 and 10 millimetres was cut
by a clean chisel. It weighed 45 2 grammes,
and had the bulk of 5.78 cubic centimetres. The
strip was well washed by hot solution of potassa,
and then repeatedly by hot distilled water anddried.
Such treatment of iron, it had been previously
found, conduces in no way to the evolution of
hydrogen gas when the metal is subsequently
heated. The Lenarto iron was enclosed in a new
porcelain tube, and the latter being attached to a
Sprengel aspirator, a good vacuum was obtained
in the cold. The tube, being placed in a trough
combustion furnace, was heated to redness by
ignited charcoal. Gas came off rather freely,
viz.-

In 35 min................5 38 cubic centimetres
In 100 min.......... .9.52
In 20 min................1'63

Carbonic oxide..0.43

Nitrogen.........0'95

9.64

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HALOXYLIN.

403

sult of the experiment with this substance showed THE vast importance to the miner of a that a firmer enclosing wall was required than Tthoroughly good blasting powder causes with powder; the effect upon the rock was more considerable interest to attach to all inventions cleaving than crushing, and on account of this relating to the manufacture of that article, property it promises considerable advantages repecially when additional advantages are over powder for the blasting of coal In the tained without a corresponding increase in the ironstone mines of Morawieza the experiment cost of production. For some time past a new was made in less firm rock, with large bores, and blasting compound-the novelty of which, howa charge of 25lb. to 30lb. of haloxylin produced an ever, consists rather in effect exceeding by one-third that of gunpowder. manipulating the materials than in the materials themselves-has Such evidence as this is sufficient to prove that been extensively used in the mines and quarries haloxylin has, at least, some advantage over of the Austrian empire, under the name of ordinary blasting powder; and when the quantity haloxylin, which appears to have given great of blasting powder annually used in Great Britain satisfaction, both from the quantity of work done is taken into consideration, it will be readily and the manner of doing it. It is one of those understood that, assuming even the smaller powders which has the property of merely burn- estimate of 30 per cent. of saving, the induceing away when in the open air, and yet exerting ment for the miners of this country to adopt it a great rending force when properly confined in will be ample to ensure, under any circumstances, the blast-hole; whilst it is not liable to ignite a fair remuneration to those undertaking the spontaneously, and cannot be exploded by permanufacture.-Mining Journal. cussion or friction. The smoke resulting from the explosion is less in volume than usual, and, in addition to this, it is free from the usual suffocating character of powder smoke; in fact, there is nothing in the residue injurious to health, or even disagreeable, so that operations can be carried on without intermission. A pound of haloxylin will occupy nearly twice the space of 1lb. of gunpowder; and as haloxylin does fully two-thirds the amount of work, bulk for bulk, as any powder now in use, it follows that a material saving of cost is effected. It is claimed that haloxylin has a tendency to cleave rather than scatter or crumble the rock in which it is used; but as this is a property possessed equally by all slow-burning powders, it may well be passed over; but the circumstance of the explosion leaving the rock free from soil or stain would, no doubt, be a great advantage in salt mines, in marble quarries, and where metallic traces should be preserved from discolouration.

ΓΝ

SHOT AND TARGETS.

the absence of any authentic details as to the results of the recent practice against the Chalmers target on the continent we reproduce the following paragraph from the Pall Mall Gazette:-The opinion which we yesterday expressed as to the worthlessness of some recent experiments at Vincennes, in which 9in. steel shot fired with 431b. of powder failed to penetrate a 54in. Chalmers target, receives strong confirmation from the fact that the same target has now been penetrated through and through with 9in. Palliser shot fired from the same gun and under precisely the same conditions. These broad results of the experiment, of which the details have not yet reached us, supplement the teaching of the former experiment, and accord with all our recent experience at Shoeburyness.. They furnish one more proof of the tremendous efficiency of the Palliser projectile and of its superiority to steel; and if our Government can only succeed, as no doubt they will, in obtaining full and trustworthy details of the experiment, we may perhaps be saved the expense of constructing another Chalmers target to fire atunless Mr. Chalmers can give us something stronger than his Vincennes target.

In 2 hours 35 min. 16:53
The first portion of gas collected had a slight The invention of haloxylin is due to Messrs.
odour, but much less than that of the natural Wilhelm and Ernst Fehleisen, of Styria; it
gases occluded from a fire by ordinary malleable consists in manufacturing an explosive compound
iron. The gas burned like hydrogen. It did of sawdust, charcoal, saltpetre, and, usually,
not contain a trace of carbonic acid, nor any hy- ferrocyanide of potassium, although the latter
drocarbon vapour absorbable by sulphuric acid. ingredient is sometimes dispensed with. The
The second portion of gas collected, consist-proportions in which they are combined are
ing of 9.52 cubic centimetres, gave by analysis- generally about 9 parts by weight of sawdust,
Hydrogen........8.26 cubic centimetres 85.68 3 to 5 parts of charcoal, 45 parts of saltpetre,
4:46 and, when the ferrocyanide of potassium is used,
9.86 1 part of ferrocyanide of potassium. The saw-
dust, which if not from a non-resinous wood
should have the resin extracted from it, is passed
through a fine sieve, and then mixed with finely
powdered charcoal (from light woods) and
powdered salt petre. The mass is moistened with
about a quart of water to the hundredweight, and
then stamped or crushed. By this means the
whole is rendered homogeneous. The mass is
now moistened again with water under ordinary
circumstances, and with a weak solution of
ferrocyanide of potassium when a quick powder
is required. The subsequent processes of caking,
granulating, and drying are conducted in the
same way as is usual in the manufacture of
ordinary powder, and the grains can, if desired,
be polished as usual, but this is found to be un-
necessary.

100'00
The Lenarto iron appears, therefore, to yield
2:85 times its volume of gas, of which 86 per cent.
nearly is hydrogen. The proportion of car-
bonic oxide is so low as 44 per cent. The gas oc-
cluded by iron, from a carbonaceous fire, is very
different, the prevailing gas then being carbonic
oxide. For comparison a quantity of clean horse
shoe nails was submitted to a similar distilla-
tion. The gas collected from 23.5 grammes of
metal (3.01 cubic centimetres) was—

In 150 min..........5'40 cubic centimetres.
In 120 min..........2.58

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In 4 hours 30 min. 7.98
The metal has given 2.66 times its volume of
gas. The first portion collected appeared to
contain of hydrogen 35 per cent., of carbonic
oxide 50'3, of carbonic acid 77, and of nitrogen |
7 per cent. The latter portion collected, gave
more carbonic oxide (58 per cent.) with less hy-
drogen (21 per cent.), no carbonic acid, the re-
mainder nitrogen. The predominance of car-
bonic oxide in its occluded gases appear, to attest
the telluric origin of iron. Hydrogen has been
recognised in the spectrum analysis of the light
of the fixed stars, by Messrs. Huggins and Miller.
The same gas constitutes, according to the wide
researches of Father Secchi, the principal element
of a numerous class of stars, of which a Lyra is
the type. The iron of Lenarto has no doubt come
from such an atmosphere, in which hydrogen
greatly prevailed. This meteorite may be looked
upon as, holding imprisoned within it, and bear-
ing to us hydrogen of the stars. It has been
found difficult, on trial, to impregnate malleable
iron with more than an equal volume of hydro-
gen under the pressure of our atmosphere. Now
the meteoric iron gave up about three times
that amount, without being fully exhausted. The
inference is that the meteorite has been extruded
from a dense atmosphere of hydrogen gas, for
which we must look beyond the light cometary
matter floating about within the limits of the
solar system.-Chemical News

It is only fair that we should supplement this by a letter from Mr. Chalmers, which subsequently appeared in the Times. The inventor of the target writes:-The results of the recent experi ments at Vincennes and Shoeburyness having left the question of shot and armour still undecided-the Palliser party claiming a complete victory for chilled shot and the French claiming the superiority for their plates-I am desirous of saying one word in favour of the backing. The 7-ton gun, with 15lb. charge, penetrates unbacked 7in. plates at Shoeburyness, and the 12-ton gun, with 431b. charge, fails to penetrate 54in. plates at Vincennes with a backing, the shot used at Shoeburyness being Palliser shot and at Vincennes steel. But the great difference in result may be due as much to the backing as to the shot. It should also be borne in mind that the target at Vincennes was only a section of a wooden ship, that I was not permitted to superintend its construction, and that the plates in the backing were placed wider apart than I recommended. Hence the target did not properly represent my system. It is generally admitted that Major Palliser has produced the best shot, and the experimental committee believe that I have produced the best backing. In order, therefore, that these principles of attack and defence may be fairly tested (if the Government refuse to give me another target with steel plates in the backing), I shall furnish one on the following conditions:-It shall be of the same weight per square foot and depth of structure as the improved "Warrior" target, with 8in. plates, and be fired at under similar circumstances. If the Palliser shot go through the target, I shall bear the expense myself; but if it fail to go through, then the expense, not exceeding £1,000, to be borne by Major Palliser. The thickest plate of my target shall not exceed 5in.

Owing to the great cost of carrying explosive materials, the importation of haloxylin from Germany is, commercially, out of the question; it is, therefore, proposed to manufacture it in this country. There are at present three factories in Styria, Hungary, and Moravia respectively, yet they are scarcely able to keep pace with the continually increasing demand, and it is to this circumstance alone that is to be attributed the fact that until now no efforts have been made to introduce it into England. The Hunyad board of the Kronstadt Mining and Smelting Company made careful comparative experiments in their Telek iron mines, and obtained with half the weight of haloxylin the same results as with the powder in ordinary use; but such a high duty as this probably resulted from some exceptional circumstance not having been taken into account; that 2lb. of haloxylin, however, will do as much as 3lb. of other blasting powder appears to have been well ascertained. The Austrian State Railway Company certify, as the result of the experiments made at their mines in the Banat, that the trials in the coal mines of Doman took place in a cross-course when very dense vapours prevailed; nevertheless, the place could be approached immediately after the blasting, no smoke being left. As to the effect, 2 oz. to 24 oz.of haloxylin are equal to 3oz. to 3 oz. of blasting powder. The re

Albert gold medal to W. Fothergill Cooke and ProThe Society of Arts have this year awarded the fessor Charles Wheatstone, F.R.S., "for their joint labours in the introduction of the electric telegraph." The medal has been struck in duplicate, and a copy will be presented to each.

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MACHINERY FOR THE MANUFACTURE

OF CRUCIBLES.

in slots formed

nuts ff on the frame c, and the right hand end is provided with a handle g, which is turned accord. ing as the former a and the block b are required HE important purposes for which crucibles to be moved. The frame c is free to move up be observed in their manufacture, in order to en-ij, and its weight is counterbalanced by weights sure that only the very best class of goods should kk on the ends of chains or cords 11 passed over enter the market. To this end Mr. T. V. Mor-pulleys m m and connected to the frame c. n is gan and Mr. E. Hyles, of the Patent Plumbago a catch on the upright j to secure the frame c Crucible Company, Battersea, have just patented in position when the former a reaches its lowsome improvements in apparatus for the manuo is the mould into which the facture of crucibles from plastic materials. Their plastic material is fed; this mould is carried on invention consists in fitting the forming tool so an ordinary lathe or jigger, p, to which rotary mothat in addition to being capable of an up and tion is imparted as usual. down movement, it is free to be moved and ad.

justed horizontally as the crucible is being moulded, and according to its required size or thickness. They also employ a lever to prevent all vibration or movement of the former when at its final position in the crucible. The invention further consists in the employment of a brake to stop the revolution of the lathe or jigger when the driving belt is moved from the fast to the loose pulley of the lathe shaft. This brake is composed of a horizontal bar hinged behind the apparatus, while its front end extends to the front of the apparatus near to the attendant. The bar carries a block r, and when the brake is to be applied the attendant by his foot moves the bar on its hinge w, so as to cause the block to bear against a collar or other revolving portion of the lathe.

In the accompanying engraving, fig. 1 is a front elevation, fig. 2 a side elevation, and fig. 3 a section through the line AA of fig. 1 of an apparatus constructed according to Messrs. Morgan and Hyles' improvements. a is the former or forming tool; it is fitted to a block b, which is free to be moved horizontally in a frame e by means of a horizontal threaded rod d taking into a corresponding thread e in a nut b) in the block b. The ends of the rod d work in fixed

est position.

When the frame c is caught by the catch n, and the mould is caused to rotate, the threaded rod d is turned by its handle g so as to cause the former a to move horizontally and spread the plastic material against the side of the mould o, and when it has been moved to the required distance, which is regulated by a scale on the frame c, the back end of a lever q carried on the top of the frame c and free to move backward by means of a slot r, is inserted into a hole s formed in an upright t, and its forward end is then pressed down by the attendant, so that this lever bears forcibly upon the frame c, and prevents vibration or movement of the former a. When the crucible is finished the handle g is turned to bring the former a to the centre of the crucible, the lever q is moved forward out of its hole s, the catch n is released, the frame c is raised up, and the mould is removed in the ordinary manner, all being then ready for the next operation. u is a horizontal bar under the platform v and hinged at w, while its front end extends to the front of the apparatus. x is a block on the bar u, and y is a callar on the lathe shaft. When it is required to stop the revolution of the lathe, the attendant moves the bar u on its hinge w, so as to bring the block a against the collar y. is a horizontal bar or guide for the bar u.

AERONAUTICS IN FRANCE,

CAMILLE FLAMMARION has underM. taken the direction of a series of balloon experiments under the scientific commission, He has made two ascents, in one case confining his observations to one zone, between 500 and 800 metres in altitude, and in the other attaining the greatest possible height under the circumstances at daybreak. In the latter case, in order to avoid all extra weight, M. Flammarion recently ascended alone from Barbison, a village on the confines of the forest of Fontainebleau, at ten minutes to four a.m. At first the humidity caused the balloon to rise very slowly, but as the sun sky was perfectly clear, and in an hour the rose the ascensional power soon increased. The altitude attained was 1,000 metres; at 5.30, it had risen to 2,000 metres; at 6, to 2,400 metres; at 6.45, to 3,000 metres; at 6.47, to 10,000ft. The difference in the amount of humidity in the air surface the hygrometer stood at 98 deg., whereas was very remarkable; at 120 metres above the at the greatest altitude reached it only marked the rarefaction of the air, produced a painful 25 deg. This excessive dryness, together with sensation in the lungs and ears. With this exception no inconvenience was felt, nor did the slightest accident occur in the descent.

The House of Commons Committee of the Lon

don, Chatham, and Dover Bills, group 12, have passed the following resolution:-"That the Com mittee cannot, at all events, sanction the raising of any additional capital, with priority over those with a full kaowledge of the circumstances of the debenture holders who do not give their consent case." And the chairman further went on to say that it must be a question of further consideration whether they would allow any priority under any circumstances.

JUNE 28, 1867.

RUCIBLES

FIG.S.

THE MECHANICS' MAGAZINE.

405

[graphic]

acid require a greater or less percentage of pig or cast iron, and the other materials or fluxes also require to be varied according to their quality. In the utilisation of slag or scoria from the smelting of such ores, the slag or scoria is used for the purpose of improving other iron that is not titanic; this is done by using the slag as a flux in the puddling furnace, or any smelting or melting furnace, whereby the iron becomes titanised, and is regulated in quantity according to the quality of the iron operated on and the purposes for which it is required.

M.

AERONAUTICS IN FRANCE CAMILLE FLAMMARION taken the direction of a series of periments under the scientific comisi has made two ascents, in one case criti observations to one zone, between 5 metres in altitude, and in the other a greatest possible height under the crus at daybreak. In the latter case, i avoid all extra weight, M. Flammarica ascended alone from Barbison, & confines of the forest of Fontainebles, minutes to four a.m. At first the hami

the balloon to rise very slowly, but w rose the ascensional power soon incred sky was perfectly clear, and in altitude attained was 1,000 metres; had risen to 2,000 metres; at 6, to, at 6.45, to 3,000 metres; at 6.47, to difference in the amount of humidi was very remarkable; at 120 metra urface the hygrometer stood at 98 de at the greatest altitude reached it 25 deg. This excessive dryness, he rarefaction of the air, produced Sensation in the langs and ears. T Ception no inconvenience was far lightest accident occur in the descent

The House of Commons Committed on, Chatham, and Dover Bile, assed the following resolutionmittee cannot, at all events, sanction the ny additional capital, with pric ebenture holders who do not give the with a full kaowledge of the circu And the chairman further w question of further d

MANUFACTURE OF ALKALI.

HE for 1866 of the Government

Tinspector appointed under the provisions of

siding at Place Napoléon, Lyons, has
patented the invention illustrated in the accom-
panying engraving. The principle of the inven-
tion lies in the cleansing and causing all the
round oleaginous grains to go out from the corn,
barley, oats, and of all cereal plants, and that
by means of a cylinder of larger dimensions
than that ordinarily used, which, pierced with
oblique holes and having a round bottom, retains
the round grains and prevents their spilling with
the corn. The inventor has increased the length
of the cylinder and diminished its diameter, so
as to have a greater yield than by the old in the
same amount of time, and to give the corn a bet-
ter cleansing, which happens through the velo-
city the cylinder acquires by reason of its
diminished diameter, and the consequent increase
in the amount of ground that the corn in the
cylinder travels over. This sorter is represented
in the accompanying engraving, which shows a
longitudinal section in elevation. The to-and-fro
movement is imparted to the cylinder B by the
pendulum A by means of the rod Q. By this to-
and fro movement the oleaginous or round grains
are taken from the cylinder by the holes so as to
allow the grains to descend until they find
orifices to get out. The old sorters were sub-
ject to being frequently repaired, the result
either of a vicious arrangement of the parts or TREATING TITANIFEROUS IRON ORES.
of wear. M. Lhuillier has remedied these in-
conveniences by the following means:-In the
R. GEORGE CRAWSHAY, of the firm of
MR
Hawks, Crawshay, and Sons, Ironworks,
old system the holes of the axis and of the two Gateshead-on-Tyne, and Mr. John Thomas, of
extremities of the forked pieces of the rod wore Newcastle-on-Tyne, have recently patented some
by reason of their constant motion and con- improvements in the treatment of titaniferous
sequently occasioned frequent and onerous re- iron ores and in extracting iron therefrom, also
pairs. This system is modified by a forked piece for utilising the scoria produced. In treating
of a single piece, the axis of which is furnished titaniferous iron ores so as the better to obtain
with an axle or axle end C, in bronze bearings. the iron therefrom they calcine the ores, and the
This prevents abrasion and renders repair easy, ores while hot are thrown into water so as to
since it is only necessary to take out the bearing disintegrate the lumps, and at the same time to
when worn out. For greater solidity in the con- convert a portion of the titanic acid into titanic
struction the bearings of the forked piece are oxide. After this the ores are properly dried,
made in steel, as also the bolts, which act as
hinges, and so as easily to adapt the forked ing. Before subjecting the ores to the operation
when they are ready for the operation of smelt-
piece, the form of the hinder part is altered, so
as to be able to adapt also bronze bearings. The of the blast they should be analysed, and this
crossbar R being liable of frequent replacing may be done either before or after the process of
through wear, a flat pin is substituted for it, calcining, in order to guide the regulation of the
which lowers by degrees as the crossbar wears, with the charges in smelting. The furnace is of
proportions of the different materials to be used
so that whatever wearing away there may be
there is never any play. In the old sorters the the ordinary construction, such as is used in the
hammer had also the inconvenience of not being smelting of iron ores, and when heated is charged
able to be changed or suppressed at will, and with the ores and following materials:-1 ton of
moreover, when the oil got to be bad and titanic iron ore; 1 ton of pig or cast iron; 3 cwt.
formed coom, it could not slide in its groove, of clay, raw or burnt; 4 cwt. of lime, chalk, or
and thus prevented it from rendering such ser- limestone; and about 15 cwt. of coke, wood or
vices as were expected from it. In the new peat; charcoal may be used with advantage, where
method the hammer P is so disposed that by it is obtainable, instead of coke. The cast iron
means of a cam forming a lever it may slide thus added to the charge becomes titanised uni-
easily, and so strike on the circle of the cylinder formly with the iron obtained from the ore.
O. In this way the hammer can neither get de-
ranged nor require repair, and offers, moreover,
the advantage of being able to suppress it at

The above proportions are altered according to the analysis, inasmuch as titanic iron ores containing a greater or less percentage of titanic

the Alkali Act has just appeared. We learn
therefrom with satisfaction that a further ad-
vance has been made in the manner of prevent-
ing the escape of muriatic acid during the
processes of manufacture of various salts, the
amount of escape last year being 073, against
0-88 of the preceding year. This improvement,
though small it be in apparent amount, is a real
benefit to the residents in the neighbourhood of
chemical manufactures, as the difference of 0.15
represents more than 15 cwt. of muriatic acid
per diem, or 4 tons per week. The condensa-
tion of the dangerous acid is thus shown to
be generally satisfactory, although some allow.
ance must still be made for leakage, which
it is difficult to estimate, and which it requires
increased vigilance and possibly an amendment
The manufacture of
chemical salts appears to be still increasing, the
amount of salt decomposed during the first year
of inspection having been 288,000 tons, in the
second 310,000 tons, and during the third (1866)
371,950 tons. The report adds:-It is possible
to do a little more by careful management of the
powers granted by the Act, chiefly by giving per-
manence to the habits begun, and giving stability
to work which had been hastily done to meet
the exigencies of the occasion, although impossi-
ble to use the Act so as to satisfy all the
demands of the public when the works are in a
very crowded district. The inspector can duly
see that the proper arrangements are made, and
that they are in order when he makes his visits.
At all other periods he must leave the public to
watch."

IMPROVEMENTS IN PHOTOGRAPHY.
HE invention which we are about describe
relates to the construction of an apparatus
for igniting and burning any powder or other
composition either in a solid or liquid state, the
flame or flash of which being sufficiently actinic
is applied for the production of photographic pic-
tures, and which has been patented by Mr.
Thomas Skaife, of 32, Sussex-place, Regents' Park.
For this purpose the apparatus consists of a
platform of metal perforated with touch-holes,
supported by springs in such a manner as to
permit of its being easily vibrated or thrown
into a tremulous motion by the touch of the finger.
Connected with the platform is a parabolic re-
flector pierced with a groove, through which
communication is made with one end of the plat
form by which it may be touched, so that by
means of the springs it may suddenly vibrate.
tinic substance being strewn upon the perforated
The deflagrating powder or other explosive ac-
platform is suddenly brought into contact with
a light from an ordinary spirit lamp placed un-
derneath it, at the same instant the platform
cates this motion to the particles of the
being thrown into vibration commuui-
powder or other substance to be ignited.
The result of this is that every particle
explodes or is ignited simultaneously, and
sitised plate in an ordinary camera, produces the
produces a flash of light which, acting upon a sen-
picture of any object laced before it. When
the picture of a near object is required the powder
may be placed over a touch-hole of the picture
of a distant object is to be taken; then the powder
may be distributed over the platform and over
several touch-holes, to all of which the light may
be applied.

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