Obrazy na stronie
PDF
ePub
[merged small][merged small][ocr errors][merged small]

stant, and regenerated the purpurins by means of alcoholic | do represent the amount found by us in the distillates, and potassa. The reactions remained unaltered.

The identity of the purpurin obtained from isoanthraflavic acid with Perkin's anthrapurpurin we have already established by a comparison of the acetyl-compounds. They have the same properties and the same melting point.

A determination of the atomic weight gave the following figure:

Obtained 66.80 per cent anthrapurpurin. The decomposition of triacetyl-purpurin according to the following equation

=

C14H3(C2H30)305+3H2O=C14H805+3C2H4O2 would yield anthrapurpurin 67.01 per cent. Perkin's conjecture that anthrapurpurin might be formed from isoanthraflavic acid is therefore demonstrated.

Flavo-purpurin is the fourth purpurin known, and is very readily distinguished from the rest by its spectrum. As to the origin of isoanthraflavic acid and anthraflavic acid, we owe its explanation to a private communication from Herr Caro, of Mannheim, according to which these two bioxyanthraquinons are formed from two distinct bisulphanthraquinonic acids, by the moderated action of alkali. A more powerful action yields respectively anthrapurpurin and flavo-purpurin. Herr Caro has sent us a small specimen of both these sulpho-acids, and we were able to satisfy ourselves that the reaction passes through the following stages exactly according to his description: a. Bisulphanthraquinonic acid. Anthraflavic acid. Flavo-purpurin.

And on the other hand

B. Bisulphanthraquinonic acid.
Isoanthraflavic acid.
Anthrapurpurin.

The authors purpose pursuing the subject further.-
Berichte der Deutschen Chemischen Gesellschaft.

CORRESPONDENCE.

ON THE PRESENCE OF ARSENIC IN THE
VAPOURS OF BONE MANURE.

To the Editor of the Chemical News.
SIR,-In a recent number of the CHEMICAL NEWS (vol.

xxxiv., p. 68) I observed a review of Dr. Adam's paper on
the above subject, and I take this opportunity of briefly
alluding to one or two points.

Your reviewer's comments on the mutual decomposition of chloride and fluoride of arsenic, &c., by sulphuretted hydrogen, when these compounds are brought together in the gaseous state, have already been disposed of by Dr. Hurter in his able letter in the CHEMICAL NEWS (vol. xxxiv., p. 81), and no further remarks on this point are necessary. For what reason your reviewer should, however, speak of the amount of arsenic evolved in the experiments detailed as being assumed, and then go on to suggest the possible presence of that element in the reagents employed, is a question which has puzzled me considerably. As regards the incrustation found on the walls of the works referred to in the paper, the amount of arsenic found by two chemists (Prof. E. J. Mills and Mr. "M") is precisely stated, and there is no assumption whatever. The figures given are the result of careful analyses. The quantities of arsenic obtained by Prof. Dittmar and myself, in the distillates from mixtures of bones, coprolites, and arsenical acid (the experiments being in imitation of the manufacturing process), do not represent the total amount of that element evolved in the process. Owing to the difficulty of completely condensing the vapours, a portion of the arsenic must necessarily have escaped. But they

the only assumption in this case is that the amount
actually volatilised must have been in excess of that
obtained. I was always under the impression that in ex-
aminations for arsenic chemists paid special attention to
the purity of the reagents employed, but I infer from the
remarks of your reviewer that such is not the case--I
am, &c.,
JAMES M. MILNE,

Chemical Laboratory,
144, West Regent Street, Glasgow.

[The friends of Dr. Adams appear somewhat sore that his charges against manure works are not at once admitted without further enquiry. The experiments of Dr. Hurter certainly seems to show that sulphuretted hydrogen does not react upon chloride of arsenic in dry air, whatever may be the exact relevancy of this important fact. Concerning ammonium sulphide, which Dr. Adams seems to include among the emanations of manure works, no objection has been raised. As to organic miasms, Dr. Hurter's letter supplies not a particle of evidence for doubting their incompatibility with an atmosphere charged with chloride of arsenic, fluorine, &c. As to the main point, the writer of the above letter even yet does not state whether the precaution of making "blank experiments" was taken. Surely when such a grave charge is brought against an important manufacture, the public, and especially the interest attacked, have a right to know, not what is usually done by "chemists," but what was actually done in this particular case. An author who goes so far as to include carbonic acid amongst the deleterious products of a manufacture has no reason to feel surprised if his statements are jealously scrutinised.-Ed. C. N.]

THERMOCHROMATISM.

To the Editor of the Chemical News. SIR,-Major Ross, the author of "Pyrology, or Fire Che mistry," is evidently labouring under a mistake when he states in his article on "Thermochromatism, or Heat Colouration" (CHEMICAL NEWS, vol. xxxiv., p. 108), “Mr. Valentin informed me that Mr. Ackroyd was examining my ingenious' hypothesis published in that work." And again, on page 109, "Although Mr. Ackroyd has not made the faintest reference to the article on colour in my published work above mentioned, which, according to Mr. Valentin, led to his investigations," &c.

When Major Ross called at the Laboratory in December

last, I introduced him to Mr. Ackroyd, who had then, for

some months past, been working on colour changes, and
the Chemical Society.
had prepared a paper, which he shortly after submitted to

I could not possibly have used the words which Major Ross puts into my mouth for the simple reason that neither I nor Mr. Ackroyd had seen what Major Ross is pleased to make me speak of as his "ingenious" hypounder an erroneous impression when he makes me say, thesis. For the same reason Major Ross must labour that the article on colour in his "Pyrology" led to Mr. Ackroyd's investigation.-I am, &c.,

[blocks in formation]

To the Editor of the Chemical News. SIR,-Seeing an article by M. H. Schwarz (CHEMICAL NEws, vol. xxxiv., p. 94) I should be happy if you would allow me to put forward the following suggestions: After obtaining the mineral that has been fused with the iron turnings, and treating it with dilute sulphuric acid, place it then-after it has been carefully dried-in a crucible (Cornish), with 1 ladles of pure litharge, I ladle of sodaash and a ladle of nitre; then mix these fluxes togethe

CHEMICAL NEWS,

Sept. 22, 1876.

Chemical Notices from Foreign Sources.

within the crucible, and add a ladle of litharge over the whole surface, covering the whole with 1 of dry powdered borax and 1 ladles common salt. The pot is now placed among the glowing cokes of a Cornish windfurnace, and carefully allowed to fuse; and when the slag has the bright red wavy fluid appearance, it is taken out, and poured into a mould; first of all 3 parts of the slag is allowed to run out. The pot is then given a twist, to collect any metal that might be hanging to the sides of it; then poured en masse into the first. This should be only the work of a few seconds, or else it will all become stiff and pasty, thus preventing it being clearly poured It is then turned out from the mould to an iron plate, and allowed to cool, when it is broken. In the centre of the slag should now be found a well-defined button of lead, which should contain all the gold. It is then beaten into a cube, cupelled in the muffle-furnace, which in about half an hour should give a pure piece of gold.

out.

I think this process saves the trouble of roasting, and also of not having to contend with the ferruginous scoriæ, as it may possibly contain small shots of lead, which decidedly would at once lessen the final result.-I am, &c.,

TRIPOLITE.

LATENT.

To the Editor of the Chemical News. SIR. The note by Dr. T. L. Phipson, on the " Tripolite of Barbadoes" reminds me of a deposit of a similar kind which I examined some time ago. It occurs in Lock Oich, one of the chain of lakes forming the Caledonian Canal, and was at one time dredged up in such quantity that it was proposed to be used for improving the land in the neighbourhood. My analysis showed it to be worthless for this purpose, as it consisted almost entirely of siliceous matter, partly fine particles of decomposed rock, and partly the remains of diatoms, most of which I found to belong to well species. Portions of the deposit were perfectly white, and, when dried, extremely light, and constituted a diatomaceous deposit of remarkable purity.I am, &c.,

Glasgow, September 18, 1876.

W. WALLACE.

133

[blocks in formation]

Influence of Sonorous Vibrations on the Radiometer.-M. J. Jeannel.-I have observed that certain sonorous vibrations determine rotatory movements in the radiometer. With the assistance of MM. Coulier and Alvergniat I have made various experiments on this subject, which I wish to lay before the Academy:-In a halfdark place three radiometers, A, B, and C, of unequal sensitiveness and perfectly at rest, were placed on the inner surface of a saloon-organ. The low notes, those of the three first octaves, determine movements of rotation. The lowest notes have the greatest action, nevertheless the sound of the drone, occasion the most rapid rotation. the fa and fa sharp of the lower octave, especially with The ut, ré, and mi, although lower, act much less. All the radiometers do not behave in the same manner, either as to the rapidity or the direction of their movements. Thus, under the influence of fa or fa sharp of the lower octave the radiometer A (the least sensitive to light) revolves at the rate of about one turn per second, with the blackened surface of the discs foremost, that is to say, in the direction opposite to the motion produced by light. The radiometers B and C (more sensitive to light) turned more slowly, and in the direction of the revolution produced by light, that is to say, with the bright side of the discs forwards. I propose to explain these facts as follows:As certain notes produce no effect, it is evident that the needle, the internal support of the "mill," must be able to vibrate in unison with the notes of the organ if a rotatory motion is to be produced. Certain vibrations of the sounding-board of the organ transmitted to the needle, impart to it circular or angular vibrations, whence results the rotation of the mill which it supports. What appears to demonstrate the soundness of this explanation is that on pressing the end of the finger on the top of the radiometer it is prevented from vibrating, and, at the same time, from revolving. The sounding-board of a piano produces analogous effects, but in a less degree. If we repeat the above experiments in a situation where the diffused light is almost sufficient to set the radiometer in motion, the low notes, even the faintest, occasion rotation in the

CHEMICAL NOTICES FROM FOREIGN ordinary direction with the bright surface of the discs for

SOURCES.

NOTE.-All degrees of temperature are Centigrade, unless otherwise expressed.

Comptes Rendus Hebdomadaires des Seances, de l'Acadenie
des Sciences. No. 7, August 14, 1876.
Thermic Formation of the Two Isomeric Propylic
Aldehyds.-M. Berthelot.-The author concludes that

the transformation of a normal and primary aldehyd into an isomeric secondary aldehyd liberates either a very small quantity of heat or none at all. He also proposes the following law :-Isomeric bodies, of the same chemical function, are formed from their elements with almost identical disengagements of heat, and the agreement exists also in the formation of their isomeric derivatives.

Thermic Researches on Hydro-sulphurous Acid.M. Berthelot. The author explains the greater stability of the ordinary hyposulphites in comparison with this new compound on the principle that, other things being equal, systems are the more stable as they have lost a more considerable portion of their energy.

Hydrated Aluminous Silicate deposited by the Hot Springs of St. Honore (Nievre).-M. Daubrée.-The composition of this mineral is represented as

[blocks in formation]

Rhodein from an Analytical Point of View.-M. E.

Jacquemin.-In a paper on erythrophenic acid (June 30, 1873), and in a memoir on "Phenol from an Analytical Lyons, 1873), it was laid down that if on adding traces of and Toxicological Point of View" (Scientific Congress at aniline to a liquid a blue colouration was obtained by means of the hypochlorite of soda, the presence of phenol might be inferred in the liquid in question. The author now considers this conclusion as too absolute, but holds that the production of rhodein cannot leave chemists in doubt. If to a certain volume of alcohol diluted with water, to 40° for instance, we add a drop of pure aniline, and then hypochlorite of soda, instead of obtaining the fugitive violet usual in aqueous solutions, we observe a yellowish colouration, passing sometimes into green, and sometimes into a permanent blue-green. If this reaction appears in a liquid which may possibly contain phenol, the presence of that body might be suspected. But to re

134

Chemical Notices from Foreign Sources.

move all doubt, the blue-green liquid, after some time, is diluted with an equal volume of water and a little of a dilute solution of the sulphide of ammonium. If aniline alone has produced the colour there appears the rosypurple of rhodein, which finally fades into a yellow. If aniline and phenol are both present, the blue reappears in all its purity, and then also passes into yellow. To distinguish these two yellows, hypochlorite of soda may be added, which in the one case restores the fugitive violet of aniline, and in the other forms the blue erythrophenate, which the next day will be found to have retained its colour.

Researches on the Derivatives of Aceto-valerianic Ether.-M. E. Demarcay.-Not adapted for abstraction. Examination of Chilian Minerals.-M. Domeyko.The minerals described are the chloro-iodide of mercury and silver from Caracoles, and polybasic sulphates of copper, often forming a cupro-ferric alum.

No. 8, August 21, 1876.

Thermic Formation of Hydroxylamin or Oxyammonia.-M. Berthelot.-Not suitable for abstraction. An Effect of Lightning during the Storm of August 18th.-M. A. Tréoul.-During the storm which came on in the morning of Friday last, I was occupied between 7 and 8 a.m. in writing at an open window. Heavy peals of thunder, which seemed to fall in the neighbourhood, took place at intervals. During the nearest, and almost simultaneously with them, small luminous columns descended obliquely upon my paper. The length of one of them was about 2 metres, and its greatest breadth I decimetre. It was obtuse at its more remote extremity, it became gradually narrower, and was not more than 3 or 4 centimetres in breadth at the surface of my table. Their appearance was that of ignited gas with imperfectly defined outlines; their colour, not very intense, was yellow, slightly reddish, like that of many flames; but at the surface of the paper, where they hovered for some seconds, they had brighter shades. I did not remark the colour of the lower part of the first colour, but the second presented the bright colours (yellow, green, and blue) of the rainbow; the third was of a very bright blue, fading away almost to whiteness in contact with the paper. There occurred no detonation, only when about to become extinguished they quitted the paper with a slight rustling or hissing comparable to that made by a drop of water thrown upon a hot plate of metal. No odour was perceplible, and the paper was neither stained nor affected. My steel pen was not acted on and I myself felt nothing.

Electric Regulator to Maintain the Movement of the Pendulum.-M. Bourbouze.-This paper requires the accompanying illustration.

Bead Lightning.-M. G. Planté.-The storm which burst over Paris on the morning of August 18 offered an instance of a kind of lightning very rare, not rightly classified by meteorologists, and calculated to throw a new light on the formation of globe lightning. Some flashes were distinctly bifurcated, but one formed as it were a chaplet of brilliant granules, diffused along a narrow luminous band. This flash, which we observed from the heights of Meudon, appeared to strike Paris in the direction of Vaugirard. Similar flashes are described by M. Th. du Moncel as having been observed during a storm at London in the night between the 19th and 20th of June, 1857. They seemed to remain for a few moments, and then seemed as if melted up into granulated light.

Equivalent Substitution of Mineral Matters which enter into the Composition of Animals and Plants.MM. P. Champion and H. Pellet.-In the ash of the flesh of different animals and of hens' eggs the phosphoric acid is almost constant, as well as the total amount of acid capable of saturating bases. For ashes of different compositions the weight of sulphuric acid saturating the bases is so much the higher as there are more bases of low

{CHEMICAL NEWS,

Sept. 22, 1876.

equivalents. The ash of veal contains more soda than the ash of beef, and the ash of the eggs of pullets present the same feature if compared with the ash of the eggs of adult hens.

Fermentation of Urine.-M. Ch. Bastian.-A reply to M. Pasteur.

PATENTS.

ABRIDGMENTS OF PROVISIONAL AND COMPLETE SPECIFICATIONS.

Improvements in the manufacture of alkalies and hydrochloric acid G. W. Hart, Grosvenor Road, South Norwood, Surrey. (Partly a communication from J. Bennet, Michigan, U.S.A.) May 29, 1875.No. 1976. This Specification describes fusing silica with chloride or sodium on the hearth of a furnace in the presence of hydrogen of vapour of water.

An improved method of and apparatus for the manufacture of gaseous liquids. A. A. Mondollot, Boulevard de Strasbourg, Paris. June 1, 1875.-No. 2001. This consists in an apparatus for the production of carbonic acid gas, whereby lime and sulphuric acid are brought into contact and mechanically agitated, or hydrochloric acid and carbonate of lime or other materials, reacting upon one another without agitation, are mingled in a convenient way.

Improvements in the manufacture of chlorine. H. Deacon, Appleton House, Widnes, Lancaster. June 1, 1875.-No. 2003. The essential feature of this invention, which relates to improvements in the production of chlorine by what is known as Deacon's process, consists in the employment of purifying materials or agents for the purpose of removing sulphuric acid from the hydrochloric acid gas employed in conjunction with heated air, and brought in contact with porous or other substances impregnated with or containing sulphate of copper, or what I have in my former Specifications termed active substances. Improvements in and in apparatus for the separation of the oily and farinaceous constituents of maize, and in the application of the some for the manufacture of various useful products. A. M. Clark, Chancery Lane, Middlesex. (A communication from L. Chiozza, Paris.) June 1, 1875.-No. 2007. The essential feature of the process consists in operating by means of rolls or screens on the grain, previously treated with a solution of sulphurous acid, and whilst it is undergoing a gradual drying; the process being applicable, with slight variation, to the manufacture of oil, of a white and sweet flour, of dextrin, beer, fermented liquors, vinegar, alcohol, starch, glucose syrup, and glucose. Improvements in the production of protosulphuret of iron and sulphuretted hydrogen gas for the extraction of copper from mother-liquors, and for other purposes. G. T. Bousfield, Sutton, Surrey. (A communication from the Société Anonyme du Cuivre Francais, Paris.) June 3, 1875.-No. 2042. The claims to this complete Specification are the new combination of apparatus and means resulting in a production of sulphuretted hydrogen gas on a large scale, and in a new manufacture which has not hitherto been practically realised, and which is attained by the construction, disposition, and grouping of the apparatus, by heating the acid for the attack before its introduction into the vessels, which hastens the reaction on the protosulphuret, and, in consequence, increases the quantity of gas, which can be disengaged in a given time by the withdrawal of the sulphate of iron at the lower part of the vessel, which permits its extraction even during the production of the gas, and gives the means of drawing off the acid to stop the disengagement of the sulphuretted hydrogen,when desired by employing a helix as a means of stirring. Also the method described for the manufacture of protosulphuret of iron.

NOTES AND QUERIES.

Our Notes and Queries column was opened for the purpose of giving and obtaining information likely to be of use to our readers generally. We cannot undertake to let this column be the means of transmitting merely private information, or such trade notices as should legitimately come in the advertising columns. Adulteration of Red Wines.-As the adulteration of red wines with aniline has been brought under our notice by the press, your readers might like to know of some ready means to detect the adulteration; and as I have not seen any very ready means published in your journal, I have taken the liberty of sending you one which I have tried with success. I first take a small quantity of port and precipitate with diacetate of lead and filter, and if the wine be pure it will be quite clear; but if it contains the least trace of aniline the precipi. tate will be coloured red, according to the amount present. I have tested it myself. Even of a grain to the litre can be seen, because with pure wine it is left quite clear like water if properly done.A. SMITH.

[blocks in formation]

CHEMICAL NEWS,}

Sept. 29, 1876.

Limited Oxidation of Essential Oils.

THE CHEMICAL

VOL. XXXIV. No. 879.

NEWS.

[blocks in formation]

THE following experiments were conducted in order to ascertain to which constituents of my solution the antiseptic and disinfecting character is to be ascribed :

Camphoric Acid Experiments.

135

evolve large quantities of oxygen, which in this state is nascent and of a powerful oxidising character. Finally, I desire to express my thanks to my friend Dr. H. W. Hake for having rendered me much help during the prosecution of this part of my investigation.

C. I now propose to treat of the more strictly scientific part of my report, and by way of introduction, I may be allowed to state that it has been established by my former OF researches, that all the members of the terpene family represented by the formula C10H16 give peroxide of hydrogen by atmospheric oxidation, and I have further pointed out that this property is undoubtedly related to cymene (C10H14) which, as obtained from various sources, also yields peroxide of hydrogen, so that any hydrocarbon containing cymen as a proximate nucleus would presumably give peroxide of hydrogen under suitable treatment. Since my last publication, I have been able through the kindness of Dr. Wright, who placed a small quantity of menthene, C10H18, at my disposal, to investigate that body according to the method instituted by me. 18.5 grms. menthene, from solid Japanese camphor, on oxidation in a current of air at a temperature of 60° C., in the presence peroxide of hydrogen was estimated by the iodide of of 100 c.c. water, gave a solution in which the amount of potassium method after forty-four hours, and found to 0'09114 grm. H2O2. A further amount was produced on continuing the oxidation. Meanwhile the oil grew yellow and thick, but was not further examined on account of the small quantity. The aqueous solution contained also acetic and formic acid, which where identified by the usual tests, and further an oily body which was deposited on concentration. This last body on oxidation with strong nitric acid (1 : 1) gave a yellow solution which was neutralised by soda, and this solution was found to give a barium salt insoluble in water, and also a precipideflagrated, was found to contain more than 64'45 per tate with nitrate of silver. This silver salt on heating cent silver (a little was perhaps lost). A small quantity of menthene derived from liquid Japan camphor by the action of zinc chloride gave similar results to those above ascribed to menthene from solid Japan camphor.

0'3 grm. of the acid in water was sufficient to preserve 400 c.c. milk unaltered for 7 days. After that a scum appeared and a cheesy taste. But it did not go solid and sour till the 11th day.

O'I grm. camphoric acid kept 50 c.c. of flour paste fresh for 11 days. On the 12th day it became sour.

o'i grm. camphoric acid preserved 50 c.c. grape juice in a warm oven from fermentation permanently so far as could be observed.

o'i grm. camphoric acid kept 15 c.c. egg albumen and 10 c.c. water fresh for 21 days. Became mouldy after

wards.

o'i grm. camphoric acid preserved 200 c.c. bitter beer unaltered for 11 days in an open vessel. It afterwards

became covered with fungus.

Peroxide of Hydrogen Experiments.
The strength of the solution used was that of Robbin's

10 volume solution.

10 c.c. preserved 400 c.c. milk for 6 days, meanwhile oxygen was slowly evolved; thick and sour on the 11th day.

5 c.c. preserved 47 c.c. grape must from fermentation for some 24 hours, then bubbles of oxygen were liberated; finally it had an odour like apples.

5 c.c. preserved 15 c.c. albumen (egg)+10 c.c. water fresh for very many days.

5 c.c. preserved 400 c.c. bitter beer unaltered for 26 days; then sour; fungus did not appear.

This limited inquiry exhausted my supply of menthene, nevertheless it supports the conclusion I stated in the third part of these researches (CHEMICAL NEWS, vol. xxxii., p. 138) to the effect that all bodies having cymene as a proximate nucleus give peroxide of hydrogen on oxidation by air. For Dr. C. R. A. Wright has (Fourn. Chem. Soc., series 2, vol. xiv., p. 2), by the action of bromine upon menthene succeeded in obtaining a terpene from it in the first place, and on further bromination, cymene. I have also demonstrated that clove terpene, C15H24, by the fact that it fails to give peroxide of hydrogen in oxidation,

5 c.c. preserved 30 c.c. flour paste for 6 days; after- does not contain cymen as a proximate nucleus. And

wards went bad.

Experiments with Salicylic Acid. o'i grm. preserved 100 c.c. bitter beer for 25 days, but gave to it a most peculiar taste-spirituous, bitter sweet. No longer observed.

o'i grm. preserved 100 c.c. milk for four days. On the 5th it was sour and cheesy, and on the 7th it stunk. o'i grm. preserved 50 c.c. flour paste for a number of days, but acquired even on the 4th day a very stale odour.

o'i grm. preserved 23 c.c. egg albumen, and 12 c.c. water fresh for 4 days. On the 5th it stunk.

These experiments, as also those with camphoric acid and peroxide of hydrogen, were all conducted during October, November, December, 1875.

I will conclude these remarks by pointing out that the solution whose properties have been described has a somewhat bitter but not unpleasant taste; it is non-poisonous, and harmless to clothing and furniture. While its antiseptic power is distributed between the peroxide of hydrogen and camphoric acid, the former of these is able to * Read before the British Association (Section B.), Glasgow Meeting.

more recently Dr. Wright has supported this statement by showing that clove terpene gives no cymene by the action of bromine. Regarding cymene (paramethylpropyl benzene C6H4(CH3) (C3H7) as a hydrocarbon constituted of proximate nuclei, I was led by a study of the subject to consider the possibility of obtaining peroxide of hydrogen by

the atmospheric oxidation of suitable compounds containing methyl, propyl, &c. And for the obvious reason that the ethers may in a sense be considered as oxides of the hydrocarbon radicles of the marsh-gas series, I fixed upon them for my first experiments.

Ordinary ethylic ether has for long been credited with the power of producing ozone, but beyond this, the subject was at the time I commenced my investigation in a similar state of mystery to that which surrounded the socalled formation of ozone by the oxidation of essential oils. That is to say nothing was known about it, beyond that there had been recognised under these conditions a principle which was mistaken for ozone, and of whose production there was no reasonable theory.

I do not propose to relate in detail my experiments, which are necessarily incomplete, but shall only state that ethylic ether gives apparently, by atmospheric oxidation,

136

Note on Anthracen Testing.

CHEMICAL NEWS, Sept. 29, 1876.

acetic ether and certainly peroxide of hydrogen. This, the principal solid impurities have higher boiling-points latter I have obtained in estimable amount, but this subject presents great difficulty in working, on account of the volatile nature of the ether chiefly, and most of its compounds and derivatives.

The following equations may possibly represent what occurs when ethylic ether is oxidised in the presence of water in the way I have described.

(1.) C2H3O+02=C2H30+H20. C2H5

(2.) C2H300+03= C2H5

[blocks in formation]

than anthracen. Then bisulphide of carbon fails to remove; that test, therefore, with these samples ceases to give correct indications of their commercial value. To correct this the anthrachinon test was introduced, and was, judging from the terms in which it was proposed, looked upon as applicable to all commercial anthracens. The appendix which soon followed showed that experience had not confirmed those anticipations, and now the kinone produced requires to be tested as to its purity, seeing that the resulting product is by no means definite. In applying the kinone test to commercial samples various minor difficulties occur, one of which is that damp samples of anthracen are apt to lose moisture during the time that to a sufficient of fine

(3.) C2H2O}O2+2H2O= C2H2O}0+ C2H30) O+H2O2. is occupied in reducing them tit of firm, to be a correct

CH3COOH HO CH3CO OH CH3COOH HO

+

=

Н

но

CHCOOH}+HỌ}

These equations may be explained as representing(1.) The oxidation of ether into acetic ether and water. (2.) The oxidation of acetic ether into the anhydride, and that into the peroxide.

(3.) The decomposition of the latter with water, simultaneously with its formation.

I believe that we must assume the formation of acetic

peroxide, a body which as yet has only been prepared by Brodie by acting on acetic anhydride with barium per

oxide.

In my experiments it would appear that ordinary atmospheric oxygen plays the same part as the oxygen of the barium peroxide in Brodie's method.

If this be so, the mode by which the peroxide of hydrogen is assumed to be formed, would give strength to my theory regarding its production from turpentine which may be represented, first as its oxidation into camphor (corresponding to ether); secondly, the oxidation of this body into camphoric anhydride, and the anhydride finally into the peroxide, which is slowly decomposed by water.

I have observed these properties and isolated the products of its change by water, but have not succeeded further.

derivatives.

My method of experiment I hope, at no distant period, to apply to all the ethers available. Meanwhile the preliminary results I have obtained in this new direction already foreshadow a system of classification of the terpene Finally, I submit that the production of peroxide of hydrogen from camphoric peroxide (in the case of turpentine), and acetic peroxide (in the case of ether), amounts to a demonstration of the existence of the radical hydroxyl in compounds, and in a sense may be considered as the isolation of hydroxyl itself.

NOTE ON ANTHRACEN TESTING.* By J. T. BROWN.

In the earlier days of anthracen manufacture, when it was obtained solely from the last runnings of oil, and when the distillation was stopped comparatively early, for the double reason of saving the bottoms of the stills and producing a good marketable pitch, the principal solid impurities were naphthalen, phenanthren, and paraffin. With samples of this description the method of testing by agitation (after washing with petroleum spirit) with a limited quantity of bisulphide of carbon gives approximate and practically useful results. When, however, the demand for anthracen increased, the tar distillers commenced to continue the distillation as far as possible, and only to stop the operation just before the point at which coking begins. This method of working gives some entirely different samples of crude anthracen, viz., those in which

Read before the British Association, Glasgow Meeting (Section B.)

ness to allow the small quantity grm.

sample of the bulk, and another and more serious one is the uncertainty caused by the occasional occurrence of accidental impurities in the quantity weighed out. To remedy these defects, and facilitate the testing, I should propose the following modification:

Weigh out 50 grms. of the crude anthracen, and measure out 250 c.c. of petroleum spirit; triturate the anthracen in a mortar with a sufficient quantity of the spirit to form a thin cream, and pour it into a weighed filter (taking care at the same time to leave in the mortar any grit or sand which may be present; rinse on to the filter any anthracen which may be round the sides of the mortar, and employ the remainder of the spirit in washing the filter and its contents. Allow them to drain, then fold carefully, press between bibulous paper, dry at about 60° to 80° C., and and from that quantity weigh out the gramme required, weigh. Crush to fine powder the contents of the filter, then proceed in the usual manner with the kinone test and appendix. In calculating the result, allowance must of course be made for the diminution in weight caused by washing the crude sample with petroleum spirit.

I would recommend the preliminary washing because it mentioned:-It yields a dry powder of perfect uniformity, has the following advantages in addition to those already from which it is easy to weigh out a small quantity.

portant impurities, one of which, paraffin, defies the kinone It removes, besides others, the greater part of two imtest, and the other, phenanthren, if present in large quantities, is not completely oxidised under a considerable time. And as the result of the removal beforehand of a large quantity of the impurity the oxidation proceeds more quietly, and the kinone obtained is more crystalline, and freer from chromium compounds.

REPORT OF THE SEWAGE COMMITTEE OF THE BRITISH ASSOCIATION.*

THIS Report was read by Dr. CORFIELD. It narrated the work of the committee during the past year at Breton's Farm, near Romford. During the months of June, July, August, and September little or no nitrogen, as nitrates or nitrites, was found in the effluent water, and from this it might hastily be concluded that for some reason or another the usual amount of oxidation had not gone on the soil; but the fact turns out to be that oxalic acid had been added to the samples (both sewage and effluent water) of these months with the view of preventing oxidation going on in them during and after collection. The true average amount of nitrogen in the sewage was 5'53 parts per 100,000, and the amount of nitrogen calculated to be applied to the farm in the sewage was 302525 tons. Of this quantity, o'1406 ton was collected in the effluent water re-pumped over the farm. It was remarkable how little the true average composition of the sewage differed from the results obtained in previous years, and the committee considered that this circumstance afforded con* Read before the British Association, Glasgow Meeting. (Section B.)

« PoprzedniaDalej »