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CHEMICAL NEWS

Ιον. 17, 16, 6.

Chemical Notices from Foreign Sources.

Industrial Applications of the Phosphide of Copper and of Phosphor Bronze.-MM. H. de Ruolz, Montchal, and de Fontenay.-The authors claim priority in the preparation and use of phosphor bronze, of which they have cast several pieces of artillery at Douai from 1854 to 1856. They consider that phosphorus, even in minute doses, when added to melted alloys containing copper prevents oxidation.

No. 18, October 30, 1876.

A New Electric Lamp designed by M. P. Jabloschkoff. M. L. Denayrouze.-The new source of light is

composed of two pieces of charcoal nixed in a parallel polition at a little distance from each other, and separated by an insulating substance capable of wasting away at the same speed as the charcoal. When the electric current Legins to pass the voltaic arc is formed between the

two uncovered extremities of the two charcoals. The

nearest layer of the insulating matter melts, is volatilised, and slowly lays bare the two rods of charcoal just as the wax of a candle progressively uncovers its wick as the combustion is propagated downwards. The heat springing

from the combustion of the charcoal is utilised for the

fusion and volatilisation of the insulating mixture. The composition of this latter may be varied indefinitely, since most earthy matters may be employed. The simplest mixture provisionally adopted consists of sand and powdered glass, which with an equal electric power gives double the light of a regulator. The author has been able to divide the light produced by a single source of the current. With a single Gramme machine of the common make he has caused three sets of charcoals to burn at once.

Distribution of Magnetism on the Surface of Magnets. MM. Tréve and Durassier.-The authors find that the more highly steel is carburetted the more the magnetism is condensed towards its extremities. On the contrary, the less it is carburetted the more the magnetism is equally spread over its surface.

Circular Polarisation of Quartz.-J. L. Soret and E.

Sarasin. Not suitable for abstraction.

Chemical Reactions of Gallium.-M. Lecoq de Boisbaudran.-When I merely possessed a few milligrms. of impure compounds of gallium I admitted, though not without reserve (Comptes Rendus, December 6, 1875, p. 1105), that the oxide of gallium is more soluble in ammonia than is alumina. Recent experiments confirm this opinion. Thus, a mixture of the chlorides of aluminium and gailium having been repeatedly treated with an excess of ammonia, the first ammoniacal solution was found very rich in gallium, and the last precipitate consisted exclusively of alumina. A single precipitation with a large excess of ammonia suffices to yield on the one hand a salt of gallium poor in aluminium, and on the other, alumina containing little gallium. If a mixture of the chlorides of aluminium and gallium is subjected to tractional precipitation with carbonate of soda the rays Gaa4170 and Ga ẞ 4031 are most intense in the first product, and subsequently go on diminishing. Still we cannot, in this manner, arrive at a satisfactory separation of gallium and aluminium. Carbonate of soda only precipitates indium after gallium. It is to be remarked that according to a theory which regards gallium as an intermediate between aluminium and indium, the precipitation of the oxide of gallium ought to be intermediate between that of the oxide of indium and that of alumina, and not to precede them both, as observation shows. The chloride and sulphate of gallium, if slightly acid, are not precipitated in the cold by acetate of ammonia, also feebly acid, but the same salts, if neutral, are rendered turbid. An excess of acetate of ammonia renders the liquid clea again, and in that case it no longer grows turbid on heating, unless a large excess of water be added. Chloride of gallium is very soluble and deliquescent. After having been dried it attracts moisture from the air and liquefies:

217

the solution if very concentrated is clear, but is rendered
turbid by the addition of water. The precipitate, doubt-
less an oxychloride, is only very slowly re-dissolved by
dilute hydrochloric acid. Thus, if it be desired to remove
all the gallium contained in an insoluble product, it is prudent
to heat it with strong hydrochloric acid. If to a concentrated
solution of chloride of gallium there is added exactly so
much hydrochloric acid that it may be diluted with water
without turbidity, we obtain a liquid which precipitates
copiously on boiling, but grows clear again on cooling.
A slightly acid solution of chloride of gallium, if dried at
a gentle heat, deposits crystalline needles or leaflets,
lium is not deliquescent.
which act strongly upon polarised light. Sulphate of gal-
Like alum, it forms with cold
water a clear solution, which becomes turbid in heat, and
grows bright on cooling. I have prepared gallium-alum
by mixing solutions of the pure sulphates of ammonium
and gallium. If protected from atmospheric dust the
liquid remains clear, but on contact with a fragment of
common alum it deposits voluminous and well-defined
crystals of ammonio-gallic alum. The existence of this
salt, therefore, is no longer doubtful.

On Terephthalic Aldehyd.-M. E. Grimaux.-Not suitable for abstraction.

Simultaneous Formation of Two Trioxyanthraquinons, and the Synthesis of a New Isomer of Purpurin.-M. A. Rosenstiehl.-This paper will be inserted in full.

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Two New Modifications of Dichlorated Naphthalin.--M. P. T. lève.-These are d-dichloro-naphthalin, CroH6Cl2; and e-dichloro-naphthalin, EC1oH6C12.

Explanatory Note on the Atomic Theory.-M. E. Bourgoin.-The few lines which follow are not designed to refute the new critical observations which have been addressed to the author in relation to his memoir on atomicity. They are merely intended to rectify two or three assertions which have been gratuitously ascribed to him, and the authorship of which he refuses to admit. He has been made to say that all atomic formulæ spring from the type-formulæ of Gerhardt. He has never put forward such an opinion. It is imagined that he admits the atomic weights of simple bodies to be proportional to their gaseous densities. He has never said anything similar, for the very simple reason that he no more believes in atoms than in the atomic theory, even as perfected by M. J. A. Le Bel.

Various Notes on Analytical Chemistry.-H. Pellet. -Reserved for insertion in full.

Ferrocyanide of Tetramethyl-ammonium.-M. L. Barth.-This compound is obtained by neutralising a solution of hydrate of tetramethyl-ammonium with hydroferrocyanic acid.-Deutsche. Chem. Ges. stagesium.-M. Skraup.-By the action of a mixture of CIO3K Action of Halogens upon Ferricyanide of Potasand HCl upon a neutral solution of ferricyanide of potassium, and by adding alcohol, the author obtained small black drops, which ultimately became a black crystalline mass. This is doubtless the same body which Bong obtained by the action of chloric acid upon ferrocyanide.

-Deutsche Chem. Ges.

Compounds of Sulpho-Urea with the Metallic Salts.--M. R. Maley.-An examination of the compounds of sulpho-urea with the zincic, stannous, and mercuric chlorides, cadmic sulphate, and mercuric iodide.-Deutsche Chem. Ges.

218

Chemical Notices from Foreign Sources.

Derivatives of Sulpho-Urea.-MM. Claus and Rimbach. The authors describe the reaction of sulpho-urea and trichlor-acetic acid.

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Now ready, in crown 8vo., with 58 Woodcuts, price 2s. 6d.,

LESSONS IN ELECTRICITY at the Royal

Institution, 1875-6.

Substitution Derivatives of Oxide of Ethylen.-M. F.R.S., Professor of Natural Philosophy in the Royal Institution of By JOHN TYNDALL, D.C.L., LL.D., E. Demole.

Researches on Ethyl- and Methyl-Oxamethan.O. Wallach and P. West.-These two papers do not admit of useful condensation,

Tetra-Substituted Ureas.-M. W. Michler.-A preliminary notice.

On Oxymercaptans.-R. Biedermann.-The author is engaged with attempts to introduce the group SH into phenol, and the group OH into thiophenol.-Deutsche Chem. Ges.

On Gaulterylen.-R. Biedermann.-The author confirms the view of Cahours that this compound is a terpen of the formula C10H16.

Action of Cyanide of Potassium upon Halogenated Compounds. MM. Claus and Beuttel.-Chloro-crotonic ether in an alcoholic solution is treated under pressure with cyanide of potassium. The products are two acids, one of which has received the name of the tricarballylic. -Deutsche Chem. Ges.

Product of the Reaction of Potassium upon the Succinate of Ethyl.-Ira Remsen.-This product, which represents the ether of a disuccinic acid, has been further examined by the author.

Amidated Acids.-J. W. Brühl.-An examination of the derivatives of a-chloro-propionic ether.

Hydrazinic Compounds of the Fatty Series.-M. E. Fischer. The compounds studied by the author are nitroso-diethylen, nitroso-diglycolamidic acid, and nitrosopiperidin. There is also a paper by the same author on the "Aromatic Hydrazinic Compounds."

Aromatic Nitriles.-V. Merz and K. Schelnberger.-Nitriles are formed by the action of yellow prussiate upon the halogenous aromatic carbides.

Action of Aniline upon Nitrobenzol.-MM. Dechend and Wichelhaus.--Already noticed.

Meta-chloro-nitro-benzol, and on certain Chlorinised Nitrogenous Compounds.-M. A. Laubenheimer. -Not adapted for condensation.

Extraction of Sulphur from Pyrites.-P. W. Hofmann.-If sulphide of calcium-e.g., the vat-waste from alkali works-is heated to dull redness in a current of sulphurous acid gas, obtained by roasting pyrites, the latter is at first completely absorbed. Sulphur then distils over, and the sulphide is converted into sulphate, which may be anew reduced to sulphide by calcination in a current of coal-gas.-Deutsche Industrie Zeitung.

On Aniline-Black.-M. Nietzki.-Reserved for insertion in full.

On Pittacal.-M. C. Liebermann.-Reserved for insertion in full.

Les Mondes, Revue Hebdomadaire des Sciences, No. 7, October 19, 1876.

This issue contains no original chemical matter.

Society of Public Analysts. We are informed on good authority that the Treasurer of the Society of Public Analysts (Dr. Stevenson) has sent in his resignation and retired from the Society.

MEETINGS FOR THE WEEK.

SATURDAY, Nov. 18th.-Physical, 3. "On the Cohesion or Capillary Action of Films of Water, especially when holding Solid Bodies in Suspension against the Action of Gravity," by Alfred Tylor.

Great Britain.

London: LONGMANS and CO.

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The School has accommodation for 120 Students, and contains an excellent Museum and a very completely fitted Chemical Laboratory for 50 Junior and 20 Senior Pupils, with water and gas at every working bench.

For all particulars, enclose a stamped envelope to the Secretary, Mr. W. BAXTER, at his office, Central Public Laboratory, Kennington Cross, London, S.E.

BERNERS COLLEGE of CHEMISTRY,

in conjunction with the SCIENTIFIC DEPARTMENT of the ROYAL POLYTECHNIC INSTITUTION. Instruction and preparation in CHEMISTRY and the EXPERIMENTAL SCIENCES under the direction of Professor E. V. GARDNER, F.A.S., M.S.A.

The Class Rooms are open from 11 to 5 a.m. and from 7 to 10 p.m. daily. Especial facilities for persons preparing for Government and other

examinations.

Private Pupils will find every convenience.

Analyses, Assays, and Practical Investigations connected with Patents, &c., conducted.

Prospectuses and ull particulars on application to Prof. Gardner at Berner's College, 44, Berners-street, W., or at the Royal Polytechnic Institution.

MO

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vation.

CHEMICAL NEWS,}

Nov. 24, 1876.

Repulsion Resulting from Radiation.

219

THE CHEMICAL NEWS. by the incandescent spiral is only moderate in air of ordi

VOL. XXXIV. No. 887.

ON REPULSION RESULTING FROM

RADIATION.-PART II.*

By WILLIAM CROOKES, F.R.S., &c.
(Continued from p. 210).

100. EXPERIMENTS were first tried in air of normal density. The pump was then set to work, and observations were taken at different heights of the gauge. The difference between the height of the gauge and that of the barometer gave the tension of air in the apparatus in millimetres of mercury; this is recorded in the first column of the following tables. The second column gives the greatest amplitude of the half oscillation of the pendulum in millimetres- the sign plus signifying attraction, and minus repulsion.

Near the centre of Table I., in the second column, are five observations to which I have affixed no sign. When trying the experiments I thought that either I had mistaken the direction of impulse, or my assistant had commenced to count the make-and-break seconds wrongly, as the movement seemed to be repulsion. Never having had repulsion at such a pressure before, I was not prepared for it; and fearing there might be an error, left the sign queried. Another series of observations were taken to re-examine this point; they are given in Table II.

TABLE I.

Tension of enclosed air, in millims. of mercury. Temp. 16° C. Bar. 772'55 millims.

Amplitude of half oscillation, in millims., at end of 40" obser

It is worthy of notice in these Tables that the attraction nary density. The attraction diminishes to a minimum between a tension of 50 millims. and 150 millims., then rises as the pressure diminishes, until, at a tension of 1.15 millims., the attraction is nearly four times what it was in dense air. Above this exhaustion the attraction suddenly drops and changes to repulsion, which at the best vacuum I could get was nearly thirteen times stronger than the attraction in air.

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220

Development of the Chemical Arts.

altering it. What I have called the neutral point, or the
point where attraction changes to repulsion, is in this
series lower than in the former. There it occurred at a
tension of about 0'3 millim. of mercury; here at about
0.8.
Neither does the previous attraction attain such
strength, although the ultimate repulsion is more intense.
The agreement is, however, sufficiently satisfactory, con-
sidering the faulty method of measurement.

There are many errors almost inseparable from this form of apparatus. The making and breaking contact by hand is not sufficiently certain, and hesitation for a fraction of a second would seriously affect the ultimate amplitude of arc. I tried making and breaking by clockwork, also by a seconds' pendulum, but there were difficulties in each plan.

Owing to the mode of suspension, there was uncertainty as to the length of the pendulum. I tried to make it the right length to beat seconds in vacuo. Assuming that I had succeeded in this, the pendulum would have executed fewer vibrations in the 40 seconds when oscillating in air, and consequently I should not have got the full benefit from the making and breaking contact, supposing these were accurately timed to seconds.

The battery-power varied, being stronger at the commencement, and gradually declining towards the end of the experiment; and even were the battery to remain constant, the spiral became much hotter, owing to the removal of the air from the apparatus, ranging from a bright red heat in air to a full white heat in vacuo.

Chromium
Arsenic

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Oxygen (by diff.)

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DEVELOPMENT OF THE CHEMICAL ARTS
DURING THE LAST TEN YEARS.*
By Dr. A. W. HOFMANN.
(Continued from p. 216.)

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Chlorine, Bromine, Iodine, and Fluorine. By Dr. E. MYLIUS, of Ludwigshafen. LANGBEIN reports that he has introduced another process in the works of the firm Gildemeister and Co., as the process of Thiercelin disregards the iodine existing as sodium iodide along with the iodic acid. This does not, however, apply to the more recent method of Thiercelin, since hydriodic acid is very readily decomposed by nitrous

Owing to the height of the centre of suspension of the pendulum from the stand of the apparatus, the slightest deviation from the perpendicular made an appreciable difference in the distance of the weight from the spiral, and thereby increased or diminished the effect of radiation. Thus the tread of a person across the floor of the labora-G. tory, or the passage of a cart along the street, would cause the image of the edge of the magnesium weight apparently to move from the cross wires in the telescope. Many of these sources of error could have been removed; bnt in the meantime having devised a form of apparatus which seemed capable of giving much more accurate results, I ceased experimenting with the pendulum.

Before proceeding to describe the apparatus subsequently employed, I may mention that a candle flame brought within a few inches of the magnesium weight, or its image focused on the weight and alternately obscured and exposed by a piece of card at intervals of one second, will soon set the pendulum in vibration when the vacuum is very good. A ray of sunlight allowed to fall once on the pendulum immediately sets its swinging. The pendulum apparatus above described was exhibited, and experiments shown with it, at the Royal Society, April 22nd, 1874, and also before the Physical Society, June 20th, 1874.

(To be continued).

COMPOUND OF CHROMIUM ARSENIC.
By R. H. C. NEVILE.

I THINK that a short notice of a compound of which I have seen no mention in any book may not be without interest to your readers. On pouring a hot and strong solution of pure chromic acid into a hot and saturated (or nearly so) solution of arsenious acid, the liquid in the first instance becomes green, still remaining transparent. If, however, it be kept at nearly the boiling point it gradually becomes opaque by reflected, but transparent by transmitted, light, and finally a dark green powder falls. On washing this powder thoroughly and analysing it, it was found to have the following composition :

* Phil, Mag. August, 1874.

acid.

The compounds of iodine find little application in manufactures, and are therefore merely produced on a small scale. Proposals for improved methods of preparation are therefore of limited interest and require but a very brief

notice.

For the preparation of the iodides of potassium, calcium, and lithium Liebigt proposes to form a solution of phosphoric and hydriodic acids by the reaction of amorphous phosphorus, iodine, and water, and to saturate the acid liquid with caustic baryta. Phosphate of baryta is precipitated and iodide of barium remains in solution, from which (Pettenkofer) any desired iodide may be obtained by precipitation by means of a sulphate. In preparing calcic iodide the acid may be neutralised with milk of lime.

Rud. Wagnert proposes to form the iodides by decomposing sulphites with iodine. For this purpose the sulphite of barium is particularly adapted, which is diffused in water and treated with iodine, yielding sulphate of baryta, marketable as blanc fixe and iodide of barium. But the process already in use of reducing sulphate of barium and decomposing the sulphide thus obtained with iodine is evidently simpler.

Fluorine.-Fluorine, which it was hoped would, in its compounds, prove capable of important industrial applications, has in no manner fulfilled the expectations entertained. Many attempts made with this view down to the year 1867 have proved fruitless. Amongst such we may remember the proposal of Weldon|| to prepare soda by

"Berichte über die Entwickelung der Chemischen Industr'e Während des Letzten Jahrzehends."

257.

+ Liebig, Ann. Chem. Pharm., cxxi., 222. Wagner Jahresber., 1862, Wagner, Bayer, Kunst, &c., Gewerbbl., 1862, 235. Wagner Jahresber., 1862, 261.

Weldon, Dingl. Pol. Journ., clxxxii., 228.

CHEMICAL NEWS,
Nov. 24, 1876.

Calculation for Analyses of Superphosphates, &c.

means of hydrofluoric acid. A solution of sulphate of soda was decomposed by means of hydrofluoric acid, obtained either by heating a mixture of magnesium fluoride and sulphuric acid, or by decomposing sodium fluoride with superheated steam. The sulphate of soda was thus to be resolved into bisulphate, which remains in solution, and natrium fluoride, which separates out. This latter salt is either converted into hydrofluoric acid and hydrate of soda by means of superheated steam or converted into hydrate of soda and magnesium fluoride by the addition of magnesia. The magnesia necessary for this purpose is obtained by heating common salt with Epsom salt (MgSO4+H2O), forming magnesia, hydrochloric acid, and sulphate of soda, which latter, as above mentioned, serves for the preparation of the sulphate of soda. The magnesium fluoride formed by decomposing the sodium fluoride with magnesia serves for the preparation of hydrofluoric acid, being heated along with the acid sulphate of soda obtained in the first operation, and thus converted into sulphates of magnesia and soda and hydrofluoric acid, the latter being again applicable for the decomposition of sulphate of soda. Thus all the materials required for the manufacture of soda are regenerated, and merely the common salt and the fuel are consumed. According to the inventor the cost of plant, fuel, &c., is smaller than in Le Blanc's process. As a shorter process Weldon suggests to convert common salt at a red heat into sulphate of soda and hydrochloric acid by means of bisulphate of soda. The sulphate of soda is then dissolved in water, and split up into sodium fluoride and bisulphate of soda by means of hydrofluoric acid, and from the sodium fluoride the hydrofluoric acid is recovered by treatment with superheated steam, hydrate of soda being the final product of this series of reactions. Notwithstanding the alleged remunerative nature of these processes neither of them has found its way into practice.

(To be continued.)

ON THE

CALCULATION OF THE RESULTS OBTAINED
FROM THE ANALYSES OF SUPERPHOSPHATES,
MANURES, &c.

By R. C. WOODCOCK, F.C.S.,
Royal Agricultural College, Cirencester.

221

required result (with great accuracy) in a far shorter time than when the ordinary method is adopted; the chances of a mistake are also greatly reduced. For every fraction of a grm. of the various precipitates obtained, the substance sought may at once be found by looking under its number in the table, and removing the decimal point as the case may require. An example is given, which I trust will at once make the matter quite clear, and show the shortness of the method:

Calculations for a Superphosphate.

P2O5 soluble in cold water, existing as CaH4P208.
I grm. gave o 1995 Mg2P2O7=19'95 per cent Mg2P207.
Required, the per cent of CaH1P208 :—

10'5405000
9*4864500

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210282975 CaH4P208.

Required, water lost by the CaH4P2O8 on ignition, to be subtracted from the total loss on ignition, which would otherwise be counted as "organic matter and combined

water":

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THERE are probably few substances met with during the
ordinary course of commercial analyses that require a
more tedious set of calculations than a superphosphate.
Having frequently to do these calculations, I was induced
to make up the following set of tables, which give the
Sought.
CaH4P208 105405 210810 316215 4'21620
Ca3P208 139639 2'79278 418917 5'58556
CaCO3 for
CaH4P208045045 0'90090 1*35135

Found.

I.

2.

3.

4.

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1.80180

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CaCO3 for

Ca3P208

1'35135 270270 4'05405 5'40540

OH2 in

Do.

CaH4P208

Do.

P205

P205

CaH4P208

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OH2 in

Do.

Call P208

CaCO3

PtC1,2KCI

CaSO4
K2O

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029583 0'59166 088749 1*18332

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9'52000
o'96435 I'15722 1*35009
I'47915 I'77498

2'02816 2.28168

2.07081

10 88000 12*24000 I'54296 173583 2.36664 2.66247

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