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The Chemical Laboratories will be open for Students daily from 9.30 a.m. until 4.30 p.m., except on Saturdays, when they will be closed at 12.30 p.m.

Fees for the Session-For six days per week, £21; for four days per week, £17 17s.; for three days per week, £13 135. Students entering the Laboratory Class at or after Christmas will be charged two-thirds of the fees for the whole Session.

Fees for shorter periods-For six months, £17 178.; for five months, £15 15s.; for four months, £13 13s.; for three months, £10 10s.; for two months, £7 7s. ; for one month, £4 4s. Students entering under this scale are entitled to work on every day during the week.

ROYAL COLLEGE OF SCIENCE FOR IRELAND, STEPHEN'S GREEN, DUBLIN.

Professor of Practical and Theoretical Chemistry.-R. Galloway, F.C.S.

Professor of Experimental Physics.-W. F. Barrett, F.R.S.E., F.C.S.

The Chemical and Metallurgical Laboratories, under the direction of Mr. Galloway, are open every week-day during the Session, except Saturday. Instruction is given in the different branches of Analytical Chemistry, including Assaying, and in the methods for performing Chemical Research. Fee, for the Session of nine months, £12; or for three months, £5; or for one month, £2.

There are four Royal Scholarships of the value of £50 each yearly, with Free Education, including Laboratory Instruction, tenable for two years; two become vacant each year; they are given to Students who have been a year in the College. There are also nine Exhibitions attached to the College, of the yearly value of £50 each, with Free Education, including Laboratory Instruction. tenable for three years; three become vacant each year. A Diploma of Associate of the College is granted at the end of the three years' course.

The Session commences on Monday, October 2nd.

ANDERSONIAN UNIVERSITY, GLASGOW.

DEPARTMENT OF SCIENTIFIC CHEMISTRY.

Professor of Chemistry.-W. Dittmar, F.R.S.E., &c. Young Professor of Technical Chemistry.-Dr. E. J. Mills, F.R.S.

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CHEMICAL LECTURES AT

WINTER SESSION.

Days and Hours.

LONDON HOSPITALS.

8 8

117

St. Bartholomew's Hosp.
Charing Cross Hospital
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St. George's Hospital
Guy's Hospital

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Dr. Debus, F.R.S., and Dr. Stevenson

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CHEMICAL LECTURES, CLASSES, AND LABORATORY INSTRUCTION.

BERNERS COLLEGE OF CHEMISTRY AND THE EXPERIMENTAL SCIENCES, 44, Berners Street, W.-Prof. E. V. Gardner, F.A.S., M.S.A. The Laboratory is open morning and evening throughout the year.

BIRKBECK LITERARY AND SCIENTIFIC INSTITUTION.Mr. G. Chaloner, F.C.S. Tuesdays, 8.30 to 9.30 p.m. Manipulation and Analysis, Saturdays, 7 to 10 p.m. CITY OF LONDon College, 52, Leadenhall Street, E.C. -Chemical Lecturer, Thos. Eltoft, F.C.S. Mondays, 7.30 to 8.30 p.m. Fee 6s. per term, or 15s. per session.

NORTH LONDON SCHOOL OF CHEMISTRY AND PHARMACY, 54, Kentish Town Road, N.W.-Mr. J. C. Braithwaite. The classes meet daily at 8 p.m. Fee 10s. 6d. per month. The Laboratory is open for Instruction in Practical Chemistry.

ROYAL POLYTECHNIC COLLEGE.-Chemical Lecturer, Mr. Thomas Eltoft, F.C.S. The Annual Course consists of three terms, each averaging ten Experimental Lectures. 7.30 p.m. Fee 6s. per term, Session 15s. Practical Chemistry, T. Eltoft, F.C.S.; fee, 12s. per term.

ROYAL VETERINARY COLLEGE, Camden Town.-Professor of Chemistry, Mr. R. V. Tuson.

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SCHOOL OF PHARMACY OF THE PHARMACEUTICAL SOCIETY OF GREAT BRITAIN, 17, Bloomsbury Square.-The school opens on Monday, the 2nd of October. Lectures on Chemistry and Pharmacy, by Professor Redwood, on Monday, Tuesday, and Wednesday mornings, at 9 a.m. The Laboratories for Practical Instruction in Chemistry as applied to Pharmacy, &c., under the direction of Prof. Attfield, will be open daily at 10 a.m. throughout the Session.

SOUTH LONDON SCHOOL OF CHEMISTRY, 325, Kennington Road.-Dr. John Muter, F.C.S. Daily, at 10 a.m. The Laboratory is open daily for Practical Instruction.

BIRMINGHAM.-MIDLAND INSTITUTE.-Mr. C. J. Woodward, B.Sc. Tuesday and Thursday, at 8 p.m.; Friday, at 7; and Saturday, at 3.

118

Development of the Chemical Arts.

{CHEMICAL NEWS,

BIRMINGHAM.-QUEEN'S COLLEGE.-A. C. Bruce, M.A. | Rhenania, the latter experimentally). Tuesday, Thursday, and Friday, at 12.

LIVERPOOL ROYAL INFIRMARY SCHOOL OF MEDICINE. -J. Campbell Brown, D.Sc. Lond.,, F.C.S. SCHOOL OF TECHNICAL CHEMISTRY, 7 and 9, Hackin's Hey, Liverpool. - Mr. A. Norman Tate. 9.30 a.m. Evening Laboratory Instruction. - Mr. Martin

COLLEGE OF CHEMISTRY, LIVERPOOL Murphy, F.C.S. The Laboratories are open from 10 a.m. to 5 p.m. daily.

LEEDS MECHANICS' INSTITUTION.-Mr. G. Ward, F.C.S. MANCHESTER GRAMMAR SCHOOL.-Mr. Francis Jones, F.C.S., F.R.S.E.

MANCHESTER MECHANICS' INSTITUTION.-Mr. M. A. Watts, M.A. Friday, 7.15 p.m.

QUEENWOOD COLLEGE, near Stockbridge, Hants.-Mr. E. W. Prevost, Ph.D., F.C.S., F.R.S.E.

SHEFFIELD BOROUGH ANALYSTS' LABORATORY, I and 3, Surrey Street. - Mr. A. H. Allen, F.C.S. Day and Evening Classes.

SHEFFIELD SCHOOL OF MEDICINE.-Mr. A. H. Allen, F.C.S.

UNIVERSITY OF ABERDEEN.-Prof. J. S. Brazier. ABERDEEN SCHOOL OF SCIENCE AND ART MECHANICS' INSTITUTION.-Mr. Thomas Jamieson, F.C.S. UNIVERSITY OF EDINBURGH.-Prof. A. Crum Brown, F.R.S.E.

SCHOOL OF MEDICINE, EDINBURGH.-Dr. Stevenson Macadam, F.R.S.E., and Mr. Falconer King.

GLASGOW UNIVERSITY.-Prof. J. Ferguson. GLASGOW MECHANICS' INSTITUTION.-Mr. R. R. Tatlock, F.R.S.E., F.C.S.

SCHOOL OF CHEMISTRY, 138, Bath Street, Glasgow. Dr. Wallace, Mr. Tatlock, and Dr. Clark. Day and Evening Classes.

CHEMICAL LABORATORY, 144, West Regent Street, Glasgow. Dr. Milne. Day and Evening Classes. ANALYTICAL LABORATORY, 88, Hope Street, Glasgow. -Dr. A. T. Machattie, F.C.S. Day and Evening Classes.

QUEEN'S COLLEGE, BELFAST.--Dr. Andrews, F.R.S., &c. QUEEN'S COLLEGE, CORK.-Dr. Maxwell Simpson. QUEEN'S COLLEGE, GALWAY.-Dr. T. H. Rowney. ROYAL COLLEGE OF SURGEONS IN IRELAND.-Dr. C. A. Cameron.

UNIVERSITY OF DUBLIN.-Dr. J. Emerson Reynolds. DUBLIN, CARMICHAEL SCHOOL.-Dr. C. R. C. Tichborne.

Sept. 15, 1876.

According to Deacon's statement more than 1000 kilos. of chloride of lime at 35 per cent are obtained from 1500 kilos. of salt, with a consumption of 1000 kilos. small coal. A small portion of the hydrochloric acid gas is lost from causes not as yet fully ascertained, but the portion which passes undecomposed through the apparatus is entirely recovered. Besides Deacon's process several other proposals have been made for obtaining chlorine, and in some cases without the use of manganese, but they have not been adopted in practice.

Thus Macfarlane* hoped to obtain soda and chlorine simultaneously by passing air over an ignited mixture of copperas and salt. Sulphate of soda and ferrous chloride are formed, which latter is converted into iron oxide and chlorine by the oxygen. The mixture of sulphate of soda and oxide of iron on reduction with coal and lixiviation with water yields sodium hydrate (easily convertible into soda) and iron sulphide which is reconverted into copperas on exposure to the air. Clemmt endeavoured to use chloride of magnesium for the preparation of chlorine; he mixed the magnesium chloride with manganese and decomposed it by a current of superheated steam.

Chloride of lime, the only form in which free chlorine is found in the market, has latterly been the subject of a number of published papers, which have not led to any material change in the manner of its preparation. The causes of its spontaneous decomposition, sometimes attended with explosions, and formerly not infrequent, have been investigated. To avoid such misfortunes it is recommended not to saturate the lime when too hot, and not to carry the process to the uttermost attainable point, and also not to pack it in barrels when still too recent and too moist. The gas which occasions the explosion of the chloride of lime casks has been found to be oxygen, and on such spontaneous decompositions the mass of the compound is converted into a mixture of chloride and chlorate of calcium. Interesting dissertations of a more scientific character concerning the nature of chloride of lime have been published by Kolb, Riche, Bobierre, ScheurerKestner, Tschigianjang, Fricke and Reimer, Crace-Calvert, brief, as the results of these researches are in part, at and Göpner, which unfortunately cannot be reported on in least, contradictory. The final solution of the question as to the constitution of chloride of lime is by no means solved. (To be continued).

REPORT ON THE

DEVELOPMENT OF THE CHEMICAL ARTS
DURING THE LAST TEN YEARS.*
By Dr. A. W. HOFMANN.

(Continued from p. 87.)

Chlorine, Bromine, Iodine, and Fluorine.

By Dr. E. MYLIUS, of Ludwigshafen. WHEN Deacon's process was first made known its industrial practicability was strongly doubted. The principal difficulties were considered to depend on the regulation of the temperature, the enormous volume of gases to be dealt with, and the considerable consumption of fuel. Since, however, the two former obstacles have been overcome by the inventor in the manner described, the process seems more and more available. In Great Britain at least 13 establishments are already working on the new process, and in Germany 2 (Kunheim and the

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

ON THE ELECTROLYSIS OF THE DERIVATIVES OF ANILINE, PHENOL, NAPHTHYLAMIN, AND ANTHRAQUINON. By M. F. GOppelsroeder.

I HAVE Completed my first experiments on electrolytic aniline-black, and I am in a condition to give the numerical results of my analyses, and the rational formula to which they seem to lead. Quite differently from the salts of aniline behave the salts of crystallised toluidin and also the salts of pseudotoluidin. The former furnish at the positive pole a brown matter, soluble in alcohol and dyeing silk and wool a yellowish brown. Pseudotoluidin distinguishes itself from it very plainly, since on electrolysis we obtain at the positive pole a reaction which agrees with that which is obtained by chloride of lime. It forms a violet colour, which is changed by dilute nitric acid or by the solution of permanganate of potash to a red colour. The mixtures of the bases aniline, toluidin, and pseudotoluidin behave differently from the separate bases. Thus an aqueous solution of 1 molecule of hydrochlorate of aniline with 2 molecules of hydrochlorate of toluidin is coloured red at the positive pole. Commercial aniline imperfectly

* Macfarlane, Dingl. Pol. Journ., clxxiii., p. 129.

+ Clemm, Dingi. Pol. Journ., clxxiii., p. 127.

CHEMICAL NEWS,
Sept. 15, 1876.

Certain New Salts of Bismuth.

119

mogen or of its electrolytic product. We shall thus arrive at substitutions by alcoholic radicals and by the phenyl series, just as we succeed by the aid of nitric acid or nitrates in producing at the positive pole nitro-derivatives and at the negative pole nitroamido-, amido-, and even azo-derivatives. The chemistry of colouring-matters will find in the researches of which I have spoken, a field so much the more fertile as the oxidations and the dehydrogenisations play the most important part in the production of colours.-Comptes Rendus.

ON CERTAIN NEW SALTS OF BISMUTH,
AND THEIR EMPLOYMENT IN THE
DETECTION OF POTASH.

By A. CARNOT.

I HAVE Succeeded in preparing certain new salts of bismuth, which are distinguished among all the salts of the same metal with mineral acids, by complete solubility in water. These are double hyposulphites of bismuth and alkalies. I shall indicate the method of preparation and the properties of these salts, and shall show that they are capable of a very interesting application in analytical chemistry. If into a slightly acid solution of chloride of bismuth we pour a concentrated solution of hyposulphite of soda, the liquid immediately takes a yellow colouration; it remains otherwise perfectly clear, and it even resumes a complete limpidity if it was at first a little dull for want of acid. It may be afterwards mixed with water in any quantity without there being produced any turbidity, provided that we employ a sufficient quantity of hyposulphite (about 3 grms. to 1 of bismuth). This liquid, left to itself, changes gradually, and so much the quicker as it is more concentrated. There is a deposit of sulphide of bismuth and a formation of sulphates, a reaction which is easily explained by the decomposition of hyposulphite of bismuth

saturated with sulphuric acid, in an aqueous solution, with an addition of ammonia, gave, at the dehydrogenising pole as a principal product, a red colour, and as a secondary product a violet colour. Methylanilin gives when employed in the form of its salts a violet colour at the positive pole. I have otherwise observed, according to circumstances, other colourations, among them a blue. Diphenylamin gives, if one of its salts is submitted to electrolysis at the positive pole, a blue product soluble in alcohol. Mixtures of diphenylamin and of ditoluylamin or of diphenylamin, ditoluylamin, and phenyltoluylamin such as are employed to produce the blue colours called diphenylamin blue, or, according to theory, triphenylated rosanilin blue, give, if submitted in the state of salt to a galvanic current, this beautiful blue colour soluble in alcohol. Methyl-diphenylamin which, as Bardy has shown, yields, with different oxidising agents a blue or violet colouring matter, undergoes the same transformation in the electrolytic way. Phenol, in an acidulated aqueous solution or in the form of phenate, gives rise at the positive pole to a brown body. The salts of naphthylamin decomposed by the current, in a neutral or acid solution, give rise to naphthylamin violet. Anthraquinon has attracted my attention. I sought first to transform it by electrolysis at a low temperature into alizarin and the latter into purpurin, but without success. I commenced then a new series of experiments, operating at a high temperature. Meeting anew with great difficulties, I obtained, however, a result which encourages me to continue my studies. I observed that on operating with caution a part of the anthraquinon is transformed into alizarin. This transformation takes place on introducing into a very concentrated solution of caustic potash anthraquinon reduced to a very fine powder, passing the galvanic current and heating almost to the melting-point of potash. The mass is coloured at first red and then violet by the formation of alizarate of potassium. But this colouration is rapidly replaced by a new red colouration, which soon changes to a yellowish brown and even to a deep brown, and consequently we obtain a violet Bi2,03,3S2O2+3HO=Bi2S2+3(SO3,HO). product mixed with unchanged anthraquinon and with Heat favours this decomposition and produces a deposit brown electrolytic products. If we continue to heat it the of sulphide in small black crystalline grains, which, under mass becomes more and more clear and finally white. If the microscope, present a cubic form. We may add any at the moment when the last red colouration presents quantity whatsoever of alcohol to the solution which has itself we reverse the current the mass again becomes just been prepared, or pour hyposulphite of soda into an violet, then red and yellowish, because without doubt alcoholic solution of chloride of bismuth without obtaining anthraquinon and even anthracen are formed again. I any precipitate. But we must remark that, if alone, the may say, moreover, in a general manner that if we do not hyposulphite of soda gives immediately a white precipitate go too far with decompositions, we may by reversing the in alcohol, where it is almost insoluble. The compound poles of the battery regenerate at the new negative pole formed, which is a double hyposulphite of bismuth and of the modified bodies, and reproduce at the new positive soda, is thus distinguished at once both from the ordinary pole the transformations that were previously produced at salts of bismuth by its solubility in water and from hypothe opposite electrode. In the electrolysis described of sulphites by its solubility in alcohol. A small quantity of the derivatives of aniline, phenol, and naphthylamin, the chloride of potassium added to the perfectly clear alcoholic positive pole plays the principal part. In the electrolysis liquid, produces immediately an abundant precipitate of a of anthraquinon it is at the negative pole that the violet siskin yellow, which collects easily, especially after some colouration commences and remains most intense during moments agitation. There is not produced, on the conthe whole of the operation. All the experiments of which trary, any precipitate in presence of chlorides of sodium, I have just spoken depend on the decomposition of water lithium, ammonium, calcium, magnesium, aluminium, or an alkaline derivative by the current. It is the elec- iron, manganese, &c.-in a word, all usual metals, which trolytic oxygen which acts in dehydrogenising, or in other are not precipitated by sulphuretted hydrogen. Only the cases it is the oxyhydryl of the potassium or of the sodium chlorides of barium and of strontium give white precipiwhich is substituted for the hydrogen of the chromogen. tates in an aqueous or alcoholic solution of hyposulphite. Up to the present time I have turned my attention The reaction of the salt of potash is therefore quite characespecially to the principal products, without losing sight teristic. It has seemed to me calculated to furnish a very of the secondary products, the study of which is necessary sensitive and very rapid process for the detection of this to arrive at a clear idea of the metamorphoses which base, a detection which is tedious and delicate by the protake place. It is also necessary to observe the gaseous cesses at present in use. It succeeds not only with a products. The action of the current on melted organic bodies, solution of chlorides but also with a mixture of chlorides proceeding as we do in mineral chemistry, will present and nitrates, and even with nitrates alone, chlorine playing especially great difficulties, whether because heat alone no part in the formation of the precipitate. It is, on the decomposes them, or because the electric conductibility is contrary, more or less incomplete in the presence of too weak; but the study of these actions ought not to be sulphates, and doubtless cannot be applied directly for the neglected. We ought to try also to arrive at the simul- detection of potash in this class of salts. We know, howtaneous decomposition of other bodies added to the ever, that it is the same with the best processes known up electrolyte, to arrive at substitution products of the chro-to the present time for the separation and the determina

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120

Chemical Constitution of the Alcohols.

tion of this base. All require a previous transformation of sulphates.

{CHEMICAL NEWS,

Sept. 15, 1876.

at the meeting of the British Association in Edinburgh,
some years ago, I drew attention to the existence of two
closely-related organic family groups, one of them having
for its parent molecule the ethylic and the other the gly-
colic alcohol. I took also the opportunity of pointing out
the natural order of succession, in which the basic and
acid members of each group are descended from their
respective parent alcohols, and to enlarge on the evident
parallelism and intimate chemical relations subsisting be-
tween these two series of derivatives. It becomes now
requisite for me to add thereto a third family group of
molecules, which have for their common progenitor the
glyoxalic alcohol. A simple comparison of these three
systems, as placed side by side in the annexed scheme,
will, I trust, enable the reader to grasp some of the che-
mical relations just referred to, while it will help to throw
a bright and powerful light upon several obscure and dis-
puted points, a full elucidation of which cannot fail to
prove of the highest theoretical value and importance.*
Taking it for granted that, within certain limits, the
formulæ embodied in the preceding scheme are well cal-
structure and arrangement of these three sets of deriva-
tives, I shall now, on the basis of these formulæ, proceed
to analyse a number of chemical reactions which-from
the more or less striking physical and chemical properties
of the resulting compounds, as well as the deep mystery
in which the majority of these reactions continue to be
shrouded-have never ceased to be regarded with special
attention and interest. In former papers on this subject
(CHEM. NEWS, vol. xxviii., pp. 87 and 103) I have already
had occasion to describe the molecular changes, when the
higher acid heterologues of the second and third family
groups make their appearance amongst the decomposition
products of certain bibasic water salts. In particular I
occupied myself with tracing the various movements of
one of the two basic hydrogen nuclei when the tartronate-
H2O2. H2O2. H2O2.
Fo202,2C2O3-2C2O3

Double Hyposulphite of Bismuth and Potash.-In view of an application of the potash compounds in analytical chemistry, I have made them the subject of a special study. Here are the principal results:-The yellow precipitate obtained in alcohol is easily soluble in water; its solution is greenish; it is, on the contrary, very insoluble in alcohol. We may then purify it from the salts which saturate it by receiving it at first on a filter, washing with alcohol, then dissolving in a little water, and precipitating anew by alcohol in excess. After one or two similar operations it may be considered as very pure. It may be then dried gently on the filter, and withstands afterwards, without change, a temperature of 100°. It keeps very well when dried, but changes rapidly if moist, notably in contact with the mother liquid, whence it has been precipitated, and which is, moreover, itself readily changeable. In these conditions, it is, at the end of some hours more or less mixed with sulphide of bismuth, which modifies the colour and composition. The neutral solution of the salt in water changes likewise and gradually deposits sul-culated to give a correct idea of the internal molecular phide. The salt precipitated by alcohol presents a crystalline aspect the more decided as it is formed more slowly. I have been able to obtain it distinctly crystallised on realising by divers methods a gradual mixture of the liquids. The difficulty always rests in the want of stability of the liquor, which ought, however, to remain a very long time in action for the formation of crystals; thus we can scarcely avoid a little sulphide being mixed with the crystals of hyposulphite. The process which has given me the best results consists in making the aqueous solution of the three substances in the required proportions (about 1 part of chloride of potassium and 3 parts of hyposulphite of soda in crystals to I part of metallic bismuth transformed into chloride) precipitating with alcohol and filtering to remove the mother-liquor, re-dissolving in water, and adding alcohol to the solution, but without producing any turbidity; then we plunge into it a dialyser, into which we pour concentrated alcohol so as to raise gradually the alcoholic percentage of the hyposulphite solution. There is formed on the sides of the vessel, and principally under the membrane of the dialyser, yellow greenish crystals, very brilliant, presenting the form of prismatic needles, very fine in general, and from 2 to 3 millimetres in length, but attaining sometimes 10 millimetres in length and millimetre in diameter. These crystals keep very well in the air without any alteration. I have made several analyses of the crystallised salt or crystalline precipitate. They have always given me results which correspond rigorously to the formulaBi203,3 S2O2+3(KÖ,S2O2)+2HO.

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is made by heat to split up into carbonic acid and the glycolate, or when the mesoxalate

H2O2. H2O2. 2C2O2,2C2O3-2C2O3

is by the same agent made to resolve itself into carbonic acid and the glyoxalate; and from these results I have been led to conclude that during the conversion of the mesoxalate into the tartronate by means of nascent hydrogen, that element must have expended its reducing energies upon the carbonous acid adjunct in preference to the more highly oxidised oxalic acid principal, a mode of viewing which is strongly supported by the fact that both the oxalate and the glyoxalate can be speedily transformed into the glycolate by means of this powerful reducing agent. It is, noteworthy, however, that on treating the latter compound with oxidising agents the resulting product is not, as might be expected, the glyoxalate, but the so-called glyoxylate, clearly showing that the two molecules of oxygen, instead of regenerating the carbonous acid adjunct with elimination of two water molecules, prefer to combine directly with the formic acid principal. If now we bring a second pair of oxygen molecules to act upon the latter compound, the resulting product is undoubtedly the oxalate, clearly showing that it is the car

*The chemical formulæ employed are generally the double of the ordinary formulæ. The notation is simplified by means of symbols representing hydrogen or bicarbon nuclei variously modified by their chemical union with different hydrocarbon and halogen adjuncts. Strokes placed above these symbols indicate the number of substituted bromine molecules in the associated hydrocarbons. The following is a list of the symbols embodied in the formulæ of the text:-(1.) Formyl in the two isomeric modifications, Fo2=2C2; H2 and 2Fo=2H; 2C2 (bromformyl, 2Fo=2Br; 2C). (2.) Methyl, Me, 2H,C; H2. (3.) Ethyl, Et=2H.C.; Hg. (4.) Acetyl in two isomeric modifications, Ac, 2H,C.; H, and 2Ac=2H,C,; 2C1 (bromacetyl, 2Ac=2H,C,Br; 2C,; dibromacetyl, 2Ac=2HC,Br1; 2C, tribromacetyl, 2Ac=2C,Br,; 2C2). H2=2; C2 = 12; O2=16.

CHEMICAL NEWS, Sept. 15, 1876.

Chemical Constitution of the Alcohols.

121

SYNOPTICAL ARRANGEMENT OF CHEMICAL FORMULE EXPRESSING THE CHEMICAL CONSTITUTION OF Three CLOSELY-RELATED ORGANIC FAMILY GRoups.

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bonous acid adjunct which has been regenerated with elimination of two water molecules. In connection with the term "glyoxylate" the reader will not fail to recall to mind a very keen and spirited controversy, regarding the true formula of that water-salt, which was inaugurated last year at one of the meetings of the London Chemical Society, where Messrs. Perkin and Debus took a very prominent part. Having carefully pondered this interesting problem from the novel and more elevated standpoint of my "Typo-nucleus" theory, I feel confident that a condensed report of the results of my speculative labours will be welcomed by many as a pleasant and profitable interlude, while fresh data are being gathered on the rich and productive soil of experimental research. I have therefore bethought myself of embodying an epitome of my researches in the present communication, and shall at once proceed to state the leading topics of my programme, which I have found it advisable to divide into two parts. In the first part I shall expound the molecular changes accompanying the substitutional action of bromine and perbromide of phosphorus on the water-salts of acetic, glycolic, glyoxylic, glyoxalic, and oxalic acids. In the second part I shall expound the molecular changes which ensue when the dry or dissolved combinations of the bromacetic, dibromacetic, and bromoglycolic acids with the alkalies, oxide of silver, and oxide of ammonium are subjected to the decomposing influence of temperature. Let us then, in the first place, inquire into the contents of the first part of my programme.

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H2O2. H2O2. F0202, 2F005

|

while the third derivative, although endowed with the attribute of stability, is, under certain conditions, prone to pass into the ẞ variety— H202.

=2C2Bг2,2F003.

As regards the molecular changes attending these metamorphoses they are believed to consist, with reference to the first two derivatives, in the splitting up of the brom- or dibrommethyl adjunct into formyl-bromide, which instantly re-unites as adjunct with the residual formic or bromo-formic acid principal; but with reference to the third derivative the molecular changes are held to consist in the splitting up of the tribrommethyl adjunct into bromo-carbonous acid, 2C2Br2, which, by its transition from the hydrocarbon type into the acid nucleus type, becomes now qualified to re-enter into chemical union with the residual bromo-formic acid principal. I have not as yet succeeded in gathering reliable data for studying the action of bromine on the glycolate and glyoxalate which, in theory, ought to give rise to the bromo-glycolate and bromo-glyoxalate. The first of these derivatives may, however, be got in another way,-namely, by treating the glyoxylate with perbromide of phosphorus, and decomposing the resulting bromoxyglycolyl-bromide, Fo2Br2,2 FoO4Br, with water, where it is plain that the molecular changes must consist in the replacement by hydroxyl of that particular bromine molecule which forms a constituent element of the dioxyformyl-bromide principal; while the second may be got as an ether salt by treating the oxalate of ethyl and potassium,— Et2O2.K202.

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Reverting again to the above-mentioned bromoxyglycolyl-bromide, the reader will bear in mind that its formation depends upon the successive action of two molecules of perbromide of phosphorus on the glyoxalate, and, being impressed with the theoretical importance of the fact that a third molecule of perbromide is yet capable of acting substitutionally upon this derivative with production of a body which is found to be identical in all respects with the dibromoxyacetyl-bromide as obtained by the action of the perbromide on the dibromacetate, I have deemed it desirable of submitting to him a full analysis of the molecular changes which mark the various stages of the process. In taking for my guide the analo

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