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CHEMICAL NEWS, New Method for the Detection of Copper, &c. 1876.

17 FILTRATE.

work, I think the chemists will bear me out in the stateRESIDUE. Contains Cu and Cd; divide into equal parts. ment that the test-tube, and not charcoal, is the proper White flocculent

Solution B.

place for the detection of substances in a qualitative lappt. = Biz(H0)6. Add a few drops Add HCl(dil) to boratory, and that the blowpipe methods should only be Confirm on char. of (NH4)HO, then strong acid reac.

used as a confirmatory test. In order to illustrate this coal by use of (NH4)2S and gent. tion;

a reddish point I will state that, were entire reliance placed in the the "Bismuth ly warm ; a yellow ppt. = CuzFeCy6. / " bismuth flux" for the detection of bismuth, errors Flux” (KI+S).

might arise ; for example, mercury and antimony—both ppt.=Cds.

members of the H2S group-give, under certain con. Bi. Cd.

Cu.

ditions, a red coat with the " bismuth flux" (4 parts S

+1 part KI). The basis of the above scheme may be stated as By taking powdered stibnite (Sb2S3) and mixing it with follows:

50 to 60 per cent sulphur, I succeeded several times in 1. The complete precipitation of copper, cadmium, and obtaining a very fine red coat, closely resembling the bismuth by potassium ferricyanide.

bismuth coat. 2. The solubility of copper and cadmium ferricyanides The objections to my scheme, so far as I have been in potassium cyanide.

able to find out, are, that students do not seem to think 3. The decomposition of bismuth ferricyanide into bis- there is much difference between “gently warm," as I muthic hydroxide by the action of potassium cyanide. term it in the scheme, and to boil hard for about half-an

4. The insolubility of cadmium sulphide and the solu. hour, thus causing a decomposition of the cyanogen bility of cupric sulphide in potassium cyanide.

compound and a deep blue colour. The second objection 5. The insolubility of copper ferrocyanide and the solu- is the evolution of cyanogen and hydrocyanic acid. bility of cadmium ferrocyanide in hydrochloric acid. Although I have not applied this method in quantitative

separations of copper, cadmium, and bismuth, yet I see The Chemical Reactions.

no reason why it should not be a good one, especially for

cadmium and bismuth. (a). 6 KCy.FeCy6+Bi2(NO3)6= BizFezCy12+6KNO3. The excellent method of precipitation of copper by use

of the battery seems to leave nothing to be desired in this Yellowish white.

direction. (6). 6KCy.FeCy6+3Cu(NO3)2 = CuzFe,Cy12+6KNO3. Fresenius gives four methods in which bismuth may be

weighed, placing the teroxide first on the list. He says

method gives generally a (c). 6KCy.Fe Cy6+3Ca(NO3)2 = Ca Fe Cy1+6KNO3. trifle too low, owing to the circumstance the bismuth

carbonate is not absolutely insoluble in ammonium car(d). Bi FeCy12+8KCy+6H,0= 2 Bi(HO)3+

bonate.

He also adds, “Were you to attempt to precipitate 2(4 K Cy.FeCy2) + 6HCy+Cyz.

bismuth by means of ammonium carbonate from solutions

containing sulphuric acid or hydrochloric acid, you would (c). CuzFe,Cy12+14 KCy=3[(KCy)2.CuCy2]+

obtain incorrect results." Every author I have consulted

says Biz(HO), is insoluble in KCy: it seems, therefore,

2(4KCy.FeCy2) + Cyz. highly probable that the decomposition of bisniuth ferri). Cd3Fe Cy12+14 KCy=3(KCy)2.CdCyz] +

cyanide by KCy into Biz(HO)6 may be used as a

quantitative method for the estimation of this metal. 2(4KCy.FeCy2)+Cyz. Furthermore, the presence of both hydrochloric acid and

sulphuric acid does not seem to interfere with the com(g). (KCyz.CuCy2+4HC1=CuCl2+2KCI+4HCy.

plete separation of the hydroxide. (h). 2CuCl2+4 KCy.FeCy2=Cu, FeCy6+4KCI.

I have quite recently noticed that if an excess of potas

sium cyanide is not added, a ferrocyanide of copper (i). CuS+4KCy=(KCy)z.CuCya+K2S.

separates on standing some time : whether this is a proto

or diferrocyanide I am unable to say. I have also noticed (). (KCy)2.CdCy2+(NH4)2S=CdS+

that occasionally a few particles of a dark-looking com. {(KCy)2(NH4)2Cy2}

pound separate, when solid potassium cyanide is used to

dissolve the ferricyanides of copper and cadmium. The (k). (KCy),(NH4)2Cy2 = 2K(NH4) Cy2 or

formation of this compound occurs immediately around { 2K'Cy-3(NH4)Cyz ļ the solid potassium cyanide, but seems to disappear by

shaking or gently warming. I proved by experiment that when copper, cadmium, In regard to cadmium, Fresenius says it is weighed and bismuth ferricyanides are treated with an excess of either as an oxide or a sulphide, giving the preference to KСy, potassium ferrocyanide is formed (see Equations d, the oxide. Yet he states that all compounds of cadmium, l, and f).

without exception, may be weighed as a sulphide, and the It is difficult to say whether Equations g and h repre- results are accurate. sent the exact chemical change that takes place, since The method of precipitation by hydrosulphuric acid there is a discussion in regard to the compound called has several objections ; for example, you must not have a “ Hatchett's Brown or copper ferrocyanide. Reindel strong acid solution, much HCỈ and HNO3 interfering gives its composition as Cuz K2FeCy12 (see 7. Pr. Chem., with the complete precipitation. ciii., 166), while this formula is called in question by The cadmium sulphide is almost invariably contami. Wyrouboff, who gives the formula Cu2FeCy6, probably nated with sulphur, which must be dissolved out with with 6 mol. H20 (see Bull. Soc. Chim. [2], xii., 98'; carbon disulphide, which the chemists will, I think, gene. xiv., 145).

rally agree with me is more or less a troublesome and The qualitative reactions for cadmium and bismuth disagreeable operation; or the sulphide may be boiled have always been a source of annoyance, and the valu. with sodium sulphite. able aid of the blow pipe has almost invariably been used Sulphur does not separate in a solution containing by the chemist to decide the presence of these elements. potassium cyanide, when a metal is precipitated by hydroWhile recognising the delicacy of the blowpipe methods sulphuric acid, or ammonium sulphide; therefore my for the detection of copper, cadmium, and bismuth, and mode of procedure would not have the objection stated the blowpipe as a most useful auxiliary in qualitative' above.

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18
British Pharmaceutical Conference.

July 14, 1875. PROCEEDINGS OF SOCIETIES. standard of the Society of Public Analysts (11'5 per cent)

has proved an encouragement to fraud, since milks are

now carefully let down to this point. The lactometer, BRITISH PHARMACEUTICAL CONFERENCE. the lactoscope, and Marchand's instrument have now

merely a historical interest, and it is surprising that they MEETING OF EXECUTIVE COMMITTEE.

should be noticed in a practical manual. The directions Fuly 5th, 1876.

for the examination of bread are little better. An analyst

who should undertake the detection of alum by the PRESENT : ---Professor Redwood, President ; Messrs. method indicated in the text would be equaily successful Frazer, Williams, Carteighe, and Schacht, Treasurer; in its presence or in its absence. The reader is not even Professor Attfield, Honorary Secretary; and Mr. Davies, and silica in his caustic alkali.

cautioned against the very possible presence of alumina

The translator, to do Assistant Secretary.

him justice, adds a foot note, in which some of the short. Thirteen candidates were elected to membership. The names of several members, whose subscriptions comings of the author are supplemented.

Under wine, we are told that the “ most common were more than two years in arrear, and to whom repeated adulteration is the addition of water!” With us, at least, written applications had been made by the secretaries, the most common adulteration is the addition of extrawere removed from the lists. Twenty-six subjects proposed for research were received the detection of this fraud and on plastering ” nothing

neous alcohol, generally rich in amylic compounds. On and considered. Professor ATTFIELD suggested that some competent should be left out of sight does not appear.

is said. Why coffee, chocolate, tea, sweetmeats, &c., member should be employed to revise and somewhat elaborate the subjects for papers" named in the current blood-stains is more in harmony with modern require

The section on the recognition and discrimination of list issued by the Conference. "In the course of thirteen

The author, however, observes :---" In the preyears the Conference had proposed some two hundred

sent state of science it is impossible to discriminate subjects for research, of which nearly one hundred had since been investigated, resulting papers forming about chemically between human and animal blood. M. Barruel, one-third of the three hundred papers which had been it is true, is able not only to accomplish this

, but also to read at the twelve annual meetings of the Conference. distinguish the blood of the various species of animals by The one hundred or so of subjects now on the list, espe.

its odour. But this test has a somewhat hypothetical

value for scientific purposes." cially the fifty or sixty which had been down for several years, required careful revision, information concerning instrument of qualitative research. Nor do we question

We have all due respect for the nose as a preliminary any work already accomplished being added to each sub

that the flesh and the blood of different species, or at ject, and some hints given as to the direction which

least groups of animals, may have distinct specific further investigation should take. Probably a few of the subjeås might now be excluded from the list altogether. exceedingly in delicacy, and that the whole amount of

odour. But remembering that the sense of smell varies The secretaries were ordered to give effect to the sug. Blood involved in such investigations is often very small, gestion.

we think this test utterly inadmissible. The Editor reported good progress in the preparation of the MS. of the Year Book of Pharmacy” for 1876.

Nor can we speak with any favour of the instructions

for the detection of human remains in the ashes of a Professor Attfield reported that since the previous fire-place. The author, indeed, practically admits their meeting of the committee he had issued about 2500 worthlessness when he says—“ These indications, howcopies of the current Year.Book.

ever, are reliable only when the certainty exists that the bones of animals have not been consumed in the

same fire-place.” How often is this certainty so absolute NOTICES OF BOOKS.

that a judicious chemist could presume to infer the presence of human remains from the occurrence of nitrogenous matter and phosphate of lime? The author justly

points out the fallacious character of another supposed Legal Chemistry: a Guide to the Detection of Poisons indication : -" It has been stated that the disengageExamination of Stains, &c., as applied to Chemica' ment of sulphuretted hydrogen upon treating the ashes Jurisprudence. By A. Naquet. Translated, with with sulphuric acid is an indication that the combustion additions, by J. P. BATTERSHALL, Nat. Sc.D., with a

of a human body has occurred (!) This reaction is, Preface by c. F. CHANDLER, Ph.D. M.D., &c. New | however, valueless, inasmuch as coal and certain vege. York: Van Nostrand.

table ashes likewise evolve the same gas when subjected The title-page of this book shows a step in the right to the same treatment." We cannot help wishing to direction. We are glad to see such misleading and illo. know what chemist can first have made so absurd a sug, gical terms as “ legal medicine," " forensic medicine," gestion. and “ medical jurisprudence” replaced by the more The section on the chemical examination of written accurate expressions used by our authors. The plan of documents supposed to have been tampered with is very the work before us is extensive, almost too much so for interesting. The following passage exposes an ingenious its compass of 178 pp. In addition to toxicology we find fraud, against which the public should be put on their instructions for the detection of adulterations in articles guard :-" The expert may possibly be called upon to of food and medicine, for the examination of blood-stains, give evidence as to the existence of a 'trompe l'oeil, &c., on weapons, clothing, &c., the determination of the as was the case in the trial of M. de Preigne, which took nature of hair, and of its original colour, the examination place at Montpellier in 1852. A ' trompe l'æill consists of writings, of sympathetic inks, of suspected coins and of two sheets of paper glued together at the edges, but alloys, and of human remains in the ashes of a fire-place. having the upper sheet shorter than the other, which, The section on alimentary and pharmaceutical substances therefore, extends below it. This species of fraud is may be pronounced thoroughly unsatisfactory. It embraces executed by writing unimportant matter on the upper merely flour and bread, olive, colza, hemp-seed, and lin- sheet and then obtaining the desired signature, care being seed oils, milk, wine, vinegar, and sulphate of quinine. ) taken that it is written on the portion of the paper proThe remarks on milk are evidently based upon old and jeđing below. The signature having been procured it is erroneous analyses, since M. Naquet states that “good only necessary to detach the two sheets in order to have milk leaves upon evaporation 7'5 to 9.5 per cent of solid a blank paper containing the signature, over which whatmatters.” We have heard a complaint that even the ever is desired can be inserted. The expert upon placing

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75

CHEMICAL NEWS,

Determination of Manganic Oxide. July 14, 1876.

ig pieces of moistened paper upon the suspected document

CORRESPONDENCE. noticed that they adhered to certain points, and that these formed a border around the paper, but passing above the signature."

REACTION OF CHROMIC ACID WITH We think that without great nicety of manipulation on

HYDRIC PEROXIDE. the part of those carrying out this fraud the signator might easily notice the greater thickness of the body of the

To the Editor of the Chemical News. document, as compared with the part where he is requested to sign.

Sır, - I think that the result of a few observations on the One of the most valuable features of the work is an action of hydric peroxide upon chromic acid may not appendix, added by the translator, containing the biblio. prove vninteresting, and may possibly be useful in the graphy of toxicology and its kindred branches of analy. course of a qualitative analysis. It has been before tical Chemistry. Not only independent works are here observed that hydric peroxide, when poured into a solu. given, but all memoirs and papers in the leading scientific tion of chromic acid, produces a considerable change in journals and in the transactions of learned societies, the the liquid. If, however, the liquid be first treated with a whole forming a most useful index.

small quantity of ether, and after the addition of the hydric peroxide it be well agitated, a blue colour will be apparent in the etherial portion of the solution. This

reaction I have been led to use as a test thus. To the The Retrospect of Medicine. Edited by W. BRAITHWAITE, solution in a small test-tube I add, first, a quantity of

M.D., and JAS. BRAITHWAITE, M.D. Vol. lxxiii. ether sufficient to form a layer of from 3 to 4 millimetres January to June, 1876. London: Simpkin and Mar. in thickness. I then add a few drops of a solution of shal.

hydric peroxide, and agitate the whole together by inverThis half-yearly issue, though replete with matter in sion. If no blue colour is then apparent in the etherial teresting to the medical practitioner, contains nothing of solution I add a few drops of strong hydric nitrate and a importance to the chemist. We find chloride of lead re. few more drops of hydric peroxide, and re-agitate the commended as a deodoriser and disinfectant, and pro. whole, when, if a chromate be present, a blue colour will nounced "the most powerful and economical agent for develop itself in the etherial layer. I have thus been eliminating sulphide of hydrogen from the atmosphere, as enabled to detect the presence of chromic acid in a solu. well as from all organic matter in a state of decomposition tion containing only sorro of its weight of potassic or putridity."

anhydro-chromate, corresponding to about sooo of chromic

acid. As far as I have seen, this test is unaffected by the Remarks on the Purification of Water and other Things. and other metals likely to occur

presence of nickel, cobalt, iron, manganese, aluminium,

in connection with By Lewis Thompson, M.R.C.S. Newcastle - upon chromium. It is, however, affected by the presence of Tyne : Daily Journal Office.

hydric acetate, which causes the ether to dissolve in the For the purification of water the author recommends aqueous solution, thereby rendering the blue colour very aluminite, the tribasic sulphate of alumina, or the same much less distinct. It is also necessary for the success of compound artificially prepared. He is, however, no the test that there should be no free alkalies present, as believer in the "disease producing matters in water," they completely discharge the blue colour from the and considers that the “proofs and evidences have wholly etherial solution. I am, &c., failed to establish any connection between the water and

R. H. C. NEVILE. any disease whatever.” There is no outcry made about

Chemical Laboratory, purifying the air, because there is nothing to be got out of

Catholic University College, Wright's Lane,

Kensington. it. " It won't pay, and consequently it cannot be 'sani. tarised.'” We commend the following passage to the attention of

DETERMINATION OF MANGANIC OXIDE. all who pay, or are intending to pay, millions for having their sewage carried out to sea, and poured, as they fondly think, into deep water:-" There is a very interest.

To the Editor of the Chemical News. ing and even amusing circumstance connected with the Sir,--In reply to Mr. Allen's query in the CHEMICAL waste of fertilising matters by the barbarous system called News (vol. xxxiv., p. 8), that gentleman will find the sewerage, and this circumstance admits of a happy illus. information he requires in any standard work on analytitration in the case of the existing metropolitan waste. We cal chemistry-for instance, in H. Rose, vol. ii., p. 110 will now examine what must of necessity happen when (French edition). But to save him the trouble of referring the London sewage is sent from the mouth of the Thames. to any work, I may state that I discovered the manganic That sewage is lighter than sea-water, and consequently oxide in a very simple manner; namely, by determining floats upon and does not mix with it, a fact very well in the first place the total quantity of oxygen, and in the known to the captains of our ships, who, though perhaps next the total quantity of manganese. These two data prevented by fogs from seeing the land, know well when are quite sufficient for the purpose. I think Mr. Allen they are approaching the mouth of a river by the change / might hesitate before he accuses chemists of counting in the colour of the water. The sewage, therefore, floats oxygen twice over, especially when demanding advice on the surface of the sea, and the most valuable portions upon so very simple a subject. ---I am, &c., of the sewage, which are also the most offensive, are not

T. L. PHipson, Ph.D. destroyed or got rid of in the way expected by the sewage London, July 9, 1876. scheme projectors, but find their way to the nearest shore, where they serve as food for animals. And what are the names of those animals? The two most numerous are

INNS OF COURT PUMPS. the mussel and the oyster; the very animals which are collected by man and sent up to London as food for the

To the Editor of the Chemical News. inhabitants, thus showing that an

Sir,—You have propable observed in the Daily News of Even handed justice

the 27th ult., a statement by Mr. W. Foster that New Returns the ingredients of our poisoned chalice

River water contained, " a short time ago," 0'004 gr. of To our own lips.

ammonia per gallon, or, to express this in more conMuch of this, quaintly and humorously as it is put, is venient language, 0·0057, part per 100,000. I have only too true.

recently made a number of analyses of New River water

20
Chemical Notices from Foreign Sources.

CHEMICAL News,

July 14, 1876. and found it remarkably free from ammonia, containing out, that a stem is more active where it has been cut even less than o‘oor part per 100,000. Referring also to through. the Registrar General's Reports of the present year, as far Animal fibrin is known to have this character in a high as I have them at the present moment before me, I find degree, and, indeed, it serves as one of the best tests for that New River water was free from ammonia in January, peroxide of hydrogen, while the latter serves a reciprocal February, and April, containing in March only o‘oor part purpose for fibrin. All facts regarding the various states per 100,000. As the figure stated by Mr. Foster of oxygen are of interest, because it is probable that would convey to any one at all acquainted with London oxygen may exist in several other forms to those with water the notion of a most alarming deterioration of the which we are at present acquainted. New River water, you will I hope excuse my troubling Thus Odling has (Chemical News, vol. xxvi., p. 296) you with these lines.

suggested the existence of a variety of oxygen," the weight Mr. Foster's statement that nitrates are among the of any given volume of which, like that of a given volume characteristic constituents of sewage is evidently a slip of of phosphorus vapour, shall furnish the weight of the the pen, the reverse being the case.-I am, &c.,

element contained in four such volumes of its several

GUSTAV BISCHOF. simplest compounds;" and of yet another variety of Analytical Laboratory, 4, Hart Street,

oxygen, " the weight of any given volume of which, like Bloomsbury, London, July 8, 1876.

that of any given volume of mercury vapour, shall furnish but the weight of the element contained in the same

volume pf its several simplest compounds." DR. J. W. HEARDER, F.C.S.

Schönbein viewed every slow oxidation as attended by

the formation of ozone, and taking the use of this word to To the Editor of the Chemical News.

imply, not the definite body bearing that name, but a SIR, ---May I ask why Mr. R. Meldola should have selected state of activity of oxygen, this appears to be true. MoreMr. Hearder in particular as having degraded the over, I have noticed that peroxides, such as those of lead Chemical Society by use of the F.C.S. after his name in and manganese, variously prepared and of accepted purity, an advertising or trade pamphlet.

when heated in vacuous tube, give oxygen which has the There are two trade advertisements in your impression power of liberating iodine from potassic iodide. But not of this week containing these initials, yet I think it would enough is known of these matters to admit of an accept. be very hard to charge Mr. J. J. Griffin (one of the adver- able interpretation.—1 am, &c., tisers) with trumpeting the F.C.S. for trade purposes; it

CHARLES T. KINGZETT. would be useless to do so, for the high character and

Pathological Laboratory, 68, Earl's Court Road, scientific attainments of that gentleman are too well

Kensington, W. known. Mr., or more correctly speaking, Dr. Hearder is well known in the West of England as a man of great ability, and especially is he respected and his talents SALARIES OF PUBLIC ANALYSTS. recognised by the inhabitants of Plymouth, where he has laboured hard for the progress of science, and the number

To the Editor of the Chemical News. of his pupils that have obtained honours in chemistry and Sır,-From the subjoined advertisement which I extract experimental physics at the public examinations will from the Dublin General Advertiser, it would appear that speak for itself. Dr. Hearder has been blind for many years, and anyone regard to the importance of recent sanitary legislation and

some of the Irish Grand Juries have peculiar views in who has attended his lectures, carried out, as they must

the status of chemists. have been, under great difficulties, will agree that instead of bringing discredit on the Chemical Society he has been

COUNTY OF LOUTH. an honour to it.-I am, &c.,

PUBLIC ANALYST:-The Grand Jury of F.C.S.

this county will, at the ensuing Summer Assizes, receive Applications, and appoint a fit and proper person to fill the office of Public

Analyst for said county, at a salary not exceeding Ten Pounds per FORMATION OF OZONE BY THE CONTACT annum, as arranged by the county at large Presentment Sessions. OF PLANTS WITH PEROXIDE

T. F. FILGATE, Secretary to Grand Jury,

County Court House, Dundalk,
OF HYDROGEN.

June 23, 1876.

None of the gentlemen who have arranged this salary To the Editor of the Chemical News.

would consider two pounds ten shillings per quarter SIR,–Under the above heading, Mr. S. Cohné, in the sufficient wages for a stable boy. It is to be hoped for CHEMICAL News (vol. xxxiv., p. 4) describes a few simple the honour of the chemical profession that the number of experiments, which, according to his interpretation, applications for the vacant post may be limited.demonstrate that plants, by contact with peroxide of I am, &c., hydrogen, develop ozone. But the evidence he adduces

PUBLIC ANALYST. is not sufficient to my mind to justify his deduction.

July 10, 1876. The results he obtained are as readily explicable on the view that the oxygen generated carries up with it a thin film or cloud of the aqueous solution containing peroxide of hydrogen, which latter body acts upon the potassic CHEMICAL NOTICES FROM FOREIGN iodide (which was the reagent he employed as a test) with the same result as ozone. Inasmuch, therefore, that

SOURCES. the test Mr. S. Cohné employed is one as readily susceptible to the influence of peroxide of hydrogen as to

Notr.-All degrees of temperature are Centigrade, unless otherwise

expressed. that of ozone, it is premature to write of the formation of ozɔne in this way:

It is in all probability a simple decomposition of per- Comptes Rendus Hebdomadaires des Seances, de l'Acade:nie oxide of hydrogen into water and nascent oxygen. I

des Sciences. No. 24, June 12, 1876. have on several occasions conducted such experiments, Experimental Criticism on Glycæmia: Physicoand have further thought that the decomposing influence Chemical and Physiological Conditions to be Obresided in the fibrin of the plant, an idea which derives served for the Detection of Sugar in the Blood.-M. some support from the fact which Mr. S. Cohné points c. Bernard.-Not adapted for abstraction.

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CHEMICAL News,

»} Chemical Notices from Foreign Sources. July 14, 1876.

21 Absorption of Free and Pure Nitrogen and Hydro- brown, methyl-aniline a red-brown, and nitro-benzin a gen by Organic Matters.-M. Berthelot.—The author brown-red. Under analogous treatment alcohol takes a describes his experiments and the apparatus employed. violet colour, the liquid giving the following reactions :

Formation and Decomposition of Binary Com- It is decolourised by hydrochloric and sulphuric acids, pounds by the Electric Emuve.-M. Berthelot.—The but the colour returns after neutralisation with ammonia. action of the effluve, like that of the spark, tends to resolve Chlorine water and sulphurous acid destroy it; a small compound gases into their constituents with the produc- quantity of caustic potassa turns it blue, whilst an excess tion of phenomena of equilibrium due to the inverse ten- of the reagent renders it a violet-red. Nitric acid gives dency to re-combination.

it a brown-violet shade, and acetic acid a brown, which Electric Transmissions through the Soil.—M. Th. like conditions the black is also attacked by: iodide of

returns to violet on saturation with caustic potassa. In du Moncel.-Not capable of useful abstraction.

ethyl, but the changes occasioned require further ex. Certain New Experiments made with the Radio-amination. meter of Mr. Crookes.-M. A. Ledieu.—The radiometer was found to continue revolving when submitted exclu. the Manufacture of Artificial Alizarin.-M. A. Rosen

On Anthraflavon and an Accessory Product of sively to a pencil of luminous rays falling parallel to its stiehl.—The author showed in 1874. (Comptes Rendus, axis. The author, however, does not draw the conclusion lxxix., p. 764) that the anthraflavon of Barth and Sennto which a superficial and systematic examination of this hofer 'if melted with caustic potassa gives simultaneous result might seem to lead. The experiment performed by rise to two colouring matters, one of which, soluble in M. Salleron at the suggestion of the author condemns decidedly the doctrine of emission as an explanation of the benzin and in alum water, dyes mordanted tissues shades

bordering upon those of alizarin, whilst the other, movement of the radiometer.

insoluble in the same liquids, approaches purpurin ; Law of Dulong and Petit.-M. Terreil.—The pro- the shades obtained in dyeing are, in brightness duct of the specific heat by the chemical equivalent is a and solidity, comparable those of madder. constant, on condition that all the bodies are taken of the The former of these colours is produced in such same gaseous volume and before all condensation. The small quantities that its examination has not been hitherto specific heat of elementary bodies taken at the same possible. The latter is more plentiful, and is an isomer of volume in the gaseous state is inversely as their chemical purpurin approaching the isopurpurin or anthrapurpurin equivalents. The specific heat of compound bodies, under of Perkin. Anthraflavon itself is a mixture of two the same condition, is inversely proportional to their che isomers of alizarin distinguished by their behaviour mical equivalents, and proportional to the condensation with bases. The one forms a soda salt very soluble in which the gaseous volumes of the simple bodies consti- water ; it dissolves in baryta water, which it colours a tuting them have undergone on combining. Simple or deep orange yellow, combines with gelatinous alumina to compound bodies which have lost the gaseous state have form an orange lake, and if melted with caustic potash a specific heat double that which they possessed when in between 135o and 150° it forms the isomer of purpurin the state of gas.

just mentioned. The other yields a soda salt sparingly Phenomena of Electric Oscillation.-M. L. Mouton. | soluble, and readily crystallisable ; it is insoluble in cold -Not adapted for abstraction.

baryta water, does not combine with gelatinous alumina, On Propylenic Chlorhydrines and on the Law of and if melted with potassa at the same temperature it Addition of Hypochlorous Acid.-M. L. Henry.-A does not give rise to a colouring matter; a litile only is purely hypothetical paper, in which the author combats formed at a higher temperature, with the destruction of a the views of M. Markownikoff.

large proportion of the substance. This second body can -M. Fr. Goppelsroeder.-The black analysed had been recalls the aspect of chrysophenic acid. This body is Elementary Analysis of Electrolytic Aniline-Black.be obtained in the form of fine silky needles, which in

bulk present the yellow colour of chromate of lead, and obtained by passing the galvanic current through an

identical with an accessory product of the manufacture of aqueous solution of pure hydrochlorate of aniline. The artificial alizarin from the works of Przibram and Co., of deposit formed at the positive electrode was purified by Praz. successive treatments with water, alcohol, ether, benzin, and again with alcohol. After this purification the substance was then dried at 110°, and appeared as a velvet

Bulletin de la Société d'Encouragement pour l’Industrie black powder. The mean result of 11 analyses was :

Nationale, No. 30, June, 1876.
Carbon

710366

Deposits of Fossil Phosphate of Lime in the Hydrogen

5*241

Departments of Ardennes and La Meuse.- An Nitrogen

15'327

account of the phosphatic strata, and of the mining opera. Chlorine

8.941

tions carried on. The phosphoric acid in the nodules.

varies from 16'3 to 31 per cent, the oxide of iron ranging 100:875

from 4:30 to 15.65 per cent. The amount of alumina This composition leads to the formula C24H24N_ci. present is not specially determined but included under the

somewhat vague heading “sand and clay.” If boiled with a dilute solution of caustic potassa this substance loses all its chlorine and is changed into a black body of a crystalline appearance with a metallic

Reimann's Farber Zeitung, reflection. The velvet-black powder is the mono-hydro

No. 22, 1876. chlorate of a base tetramine, C24H20N4, which forms mono-acid salts very readily. The black obtained by the J. Wagner proposes to protect alizarin steam reds from electrolysis of hydrochlorate of aniline has the formula the injurious adion of the steel " doctors” by adding C24H20NA+HCI, and that from the sulphate must there. 20 grms. sulphocyanide of potassium to each litre of fore be, 2(C24H20N4+H2SO4). If the electrolytic black colour. Sulphocyanide of ammonia is not effective. is heated vapours of aniline are given off and a violet colouring matter sublimes. If aniline-black is treated in

No. 23, 1876. sealed tubes at not less than 190° (up to 150° there is no Häitra is the name of a vegetable substance recently action)with aniline, methyl-diphenylamin, pseudo-toluydin, introduced into commerce for thickening, colours and methyl-aniline, and nitro-benzin ; these substances attack giving body to textile wares. To prepare it for use, it is the black and become coloured, aniline taking the violet, first washed, and then boiled at 130°* in a closed vessel methyl-diphenylamin a brown, pseudo-toluydin a violet | with 60 parts of water.

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