of the symbol represents the poles equidistant with the | to the planes C and to a centre. The former of these,

it is the di-rhombohedron, and consists of two correlative rhombohedra building up a double pyramid, its faces being sosceles triangles. The poles that lie on the 2 sides of discussed, the kind represented by the symbol ar {h kl}

FIG. 12.

Of the numerous mero-symmetrical forms of this system, the general characters of which were described by the lec turer, two in particular were considered which belonged to the hemi-systematic variety. The first presented symmetry only to the planes S and to a centre, the other only

I have remarked that if on packing a batch of caustic soda the slightest turbidity appear, the finished product will on cooling be very inferior. If a drum of such caustic be broken up, the section will probably show a white ring or corona, where the mass has first cooled, but which gradually changes to a dirty grey towards the central or last solidified portion. And it might be fairly imagined by any one inspecting a drum of this unsatisfactory character, that samples taken from the bad core would produce either a tinted solution, or would contain a pretty fair amount of insoluble matter. Such, however, is not usually the case, for even the most hopelessly bad pieces generally give, together with a perfectly colourless solution, the veriest trace of a beautiful white sediment consisting of lime. Occasionally, however, a little iron is present, but the two combined rarely exceed to of a per cent. Sometimes also alumina separates on neutralising the clear liquor with an acid, showing aluminate of soda to have been present. This latter is not a little singular, for the bottoms invariably contain alumina, and why the caustic soda should at an odd time take up a portion seems rather curious. Sometimes in inferior looking samples of caustic soda the aluminate is present without any other impurity exhibiting itself, which would go to prove the insolubility of aluminate soda in the concentrated hydrate.

The caustic drums should never be packed straight ahead till completely full, but by three or four instalments. In the former case, as it cools, it contracts or withdraws from the centre, leaving a hollow core right through the axis of the drum, and causes a loss in drums of nearly 10 per cent, equal to Is. 6d. to 2s. per ton of caustic soda.

In the manufacture of caustic soda, the water employed is an item of considerable importance, for in the production of every ton of 70 per cent, no less than 14 tons water must be converted into steam; and it is rather strange that, with one or two solitary exceptions, not the slightest attempt is made to utilise the enormous waste and loss of heat. I feel quite satisfied that by judiciously fixing a hood over the boat-pans or caustic pots, communicating with some simple description of surface condenser, not only could a considerable amount of water be saved, but the expenditure of steam for causticising, &c., might be also materially lessened. But it requires a little courage on the part of managers to move out of the beaten track, for in Lancashire especially there is little sympathy with failures.

The production of salt cake (including "bottoms," if sold) is, in well-conducted works, 54 to 57 per cent of 60 per cent caustic soda, and the proportion of "bottoms" is 9 to 11 per cent of the good caustic. If, however, much "red" liquor from the soda ash department be used, this proportion will be larger, or say 12 to 14 per cent.

The amount of salt necessary for reduction to 60 is 15 to 16 per cent of the caustic soda packed, though it varies considerably; and the amount of nitre is 1 to 2 per cent, Reckoning, however, to be recovered in the form of caustic alkali, the real loss only amounts to to I per cent. The total quantity of fuel for all purposes should not exceed 6 to 6 tons, but in many works the consumption is over 7 tons per ton of caustic soda. It may be divided as follows:

The raw materials and total expenses per ton of 60 per cent may be put down as follows:£ s. d.

Fuel, say 6 tons, at 75. od.

Salt cake, 37 cwts.

" 38. 3d.

Limestone, 22

os. 4d.

:::

4260

CHEMICAL NEWS,
April 9, 1875.

Office expenses and management
Interest on capital, depreciation, stores, &c.

Total cost f.o.b. Liverpool....

I have but briefly entered into the manufacturing details of cream caustic soda, my desire being principally to describe minutely those of white. The colour is due to the presence of peroxide of iron, which is held in solution or suspension by the soda at its comparatively low finishing temperature, but which separates on solution of the caustic in water. Tate suggests the presence of ferrate of sodium, which would be decomposed on treatment with water.

If the cream caustic be prepared from uncausticised "red" liquors, a considerable quantity of nitre is necessary, namely, about 1 cwt. per ton of soda produced. In the latter case, also, much less fuel is required, as in place of being evaporated down from about 15° T. the concentration of the liquors only commences at about 60°, that being their average strength.

PROCEEDINGS OF SOCIETIES.

CHEMICAL SOCIETY.

Anniversary Mecting, Tuesday, March 30th, 1875.
Professor ODLING, F.R.S., President, in the Chair.

THE President, Dr. ODLING, in his annual address, con-
gratulated the Fellows on the satisfactory state of the
Society; the number of Fellows was now 801, 84 having
joined the Society during the past year, whilst, hy re-
movals, resignations, and deaths, they had lost 16. The
names of the Fellows deceased were Thomas Anderson,
M.D., T. W. Burr, H. Dircks, D. Hanbury, F.R.S., F. C.
Matthews, Henry Matthews, Henry Medlock, Ph.D.,
Mr. J. Starks, and Col. P. Yorke, F.R.S. The communi-
cations made to the Society during the past year were 65
in number, the largest ever sent in in any year since the
foundation of the Society. The President then alluded to
the very successful Faraday lecture recently delivered by
Dr. Hofmann, and, on behalf of the Society, tendered his
thanks to Professor Nevil Story Maskelyne, for the course
of lectures on Crystallography which he had given.

In evidence of the greatly increased activity of the Society, he might say that the average number of Fellows in the three years ending March, 1872, was 586, and the number of communications 30 per annum; whilst in the three years ending March, 1875, the number of Fellows was 739, and the number of communications had increased to 59. The development of chemical industry in its application to the manufacture of so-called organic products had been very striking during the last twenty years, and thus the practical fruit of the pursuit of abstract chemical science had again largely contributed to the progress of abstract investigation, since many of the compounds, manufactured on a large scale, are amongst the most valuable raw materials of the scientific chemist.

The analytical methods for the detection of food adulteration which, with few exceptions, had long been in a most unsatisfactory condition, are now being replaced by others more trustworthy and more accurate. With regard to the general policy of adulteration acts, however, it 5 6 should not be forgotten that legislative interference with manufactures of any kind was far from conducive to 7 4 manufacturing progress.

3

158

Society of Public Analysts.

{CHEMICAL NEWS,

April 1875.

but this would most probably be unstable, and be at once changed into NO.BrC=CBr.NO.

Dr. HOFMANN said, it should be remembered that Kekulé had not only proved that chloropicrin is produced by the action of chlorine on the fulminates, but also that chloride of cyanogen is formed; if, however, they went on investigating the matter at Berlin, and Dr. Armstrong did so here, they would doubtless arrive at some definite notion of the constitution of the fulminates.

was struck with the identity in composition between ful- | self intended to study the action of bromine on the fulmi minate and cyanate of silver, and had a great desire to nates, in hopes of obtaining a compoundfind some cyanogen product amongst the products of deNO.Br(C=C(NOBr"), composition, and in many places states his conviction that urea would be found. Dr. Steiner, who has recently worked on this subject in the Berlin laboratory, finds that urea is one of the most frequent products of the decomposition of the fulminates. Aniline was first tried; this acts violently on the fulminates, yielding two substances, one of which is monophenyl urea and the other diphenylguanidine; with toludine similar substances are produced. The action of ammonia itself was then examined, and it was found that when the fulminate is heated with it, it at once yields urea and guanidine. These, however, are only the ultimate products; for if mercury fulminate be digested with ammonia at a low temperature, a compound (C.NH4.NO2.CN C.NH.NO2.CN

Hg" is formed, and this, when heated, gives besides urea and guanidine, various substances, which crystallise with the greatest facility, amongst which he might mention two bodies having the composition C-H13N11O3 and C6H1N903. Again, Dr. Gladstone, many years ago in Liebig's laboratory, tried the action of sulphuretted hydrogen on silver fulminate, and obtained ammonium sulphocyanate. These experiments were afterward repeated by Kekulé, who found, however, that only a portion of the carbon went to form the sulphocyanate, another portion being given off as carbonic acid. Dr. Steiner has recently passed sulphuretted hydrogen through mercury fulminate, suspended in anhydrous ether; mercury sulphide is formed, and the ethereal solution, when allowed to evaporate spontaneously, leaves a residue consisting of ammonium sulphocyanate and a magnificent white crystalline substance, C-H8N4O6S2, which is insoluble in water, and is left behind when the product is treated with❘ water. This new compound only exists at temperatures below 24°, above that temperature it splits up with violent ebullition, thus :—

C5H8N4O6S2=2NH,CNS+3CO2.

It is perhaps formed from fulminic acid, thus:

6CHNO+3H2S=C5H8N4O6S2+CNS.NH4.

The other communication he had to make was a simple experimental illustration, to show that when chlorine displaces oxygen, only one volume of the latter is liberated for every two of the former absorbed. It was well known that when a solution of chloride of lime was heated with a little sesquioxide of cobalt, or nickel oxygen was evolved, so that if chlorine were passed into a boiling solution of caustic soda containing some of the sesquioxide suspended in it, it would be absorbed, and oxygen given off. A long tube, about a metre in length, sealed at one end and closed at the other with a stopcock is filled with chlorine, and then about 20 or 30 cubic centimetres of soda solution, containing suspended in it some freshly precipitated sesquioxide of nickel, is allowed to run in. If the tube be now heated in a water-bath, and, when cold, the stopcock is opened under water, it will rush in until the tube is half full. The two volumes of chlorine have disappeared, and the one volume of gas now in the tube will be found to be pure oxygen.

Dr. ARMSTRONG said that for some months past he had been working on the fulminates, and he believed that Kekulé's formula, C.NO2.CN.H2, which made fulminic acid the nitro-derivative of cyanomethane, was not so well founded as was generally supposed. Meyer, by the action of nitrous acid OH.NO on secondary nitropropane, C(CH3)2H.NO2, obtained a body C(CH3)2.NO.NO2, but the action was different with primary nitropropanes; the ethyl compounds, for example, yielded C(CH3) (NOH)NO2. It seemed probable that fulminic acid was not a nitroderivative, but perhaps a compound NO.HC=C(NOH)". The results obtained in Dr. Hofmann's laboratory might perhaps be explained on this hypothesis, but they would no doubt lead to the elucidation of this matter. He him

The meeting was then adjourned until Thursday, April 15th, for which the following papers are announced: (1) "On the Gases Enclosed in Coals from the South Wales Basin," by J. W. Thomas; (2) " On Narcotine, Cotarnine, and Hydrocotarnine," by G. H. Beckett and Dr. C. R. A. Wright; (3) "Note on Isomeric Change in the Phenol Series," by Dr. H. G. Armstrong; (4) "On Andrewsite and Chalkosiderite," by Professor Nevil Story Maskely ne; (5) " An Examination of Methods for Effecting the Quantitative Separation of Iron Sesquioxide, Alumina, and Phosphoric Acid," by Dr. W. Flight.

SOCIETY OF PUBLIC ANALYSTS.

THE following cases of successful prosecution for the adulteration of milk will be found to be of interest to many Public Analysts, involving as they do several points upon which much difference of opinion exists, such as whether abstracting the cream from milk can properly be regarded as an adulteration, and whether the personal attendance of the Analyst, in the absence of any scientific evidence on behalf of the defendant, should be required to confirm his certificate.

It will be seen from these cases that neither in Wales nor in Ireland has the Act of 1872 been allowed to become a dead letter; and it will also be noticed, from the amount of the penalties inflicted, that the magistrates appear to be of a less tender-hearted type, in their feeling towards offenders, than many of the Metropolitan ones.

MILK PROSECUTIONS.

At the Swansea Police Court, a milk dealer was summoned for unlawfully selling, as pure or unadulterated, certain milk which was then and there found to be adulterated, or not pure. Mr. Smith appeared for the defendant. The inspector deposed that on the morning of the 11th day of March he met the defendant, and asked him if he sold milk; he replied "Yes," and he then purchased a pint of him, for which he paid 21d. He put twothirds into a bottle which he sealed, and the remaining one-third he put into another bottle, which he sealed and gave to the defendant. He then told him he was going to have the milk analysed, and that he could accompany him to Dr. Morgan with the sample if he chose. He, however, did not do so. Dr. Morgan, the Public Analyst, was then sworn, and handed in his certificate of the result of his analytical test. The sample contained 80 per cent of genuine milk, and 20 per cent of skimmed milk.

Mr. Smith made a powerful defence to the Bench on behalf of the defendant. He said that all the constable bought was milk and nothing but milk, and they were not charged with selling anything but milk. A great deal had been said about adulteration, and he could not for one moment wish to uphold adulteration; but at the same time he must do his duty to his client, and he contended that adulteration could not be by simply taking away one of the component parts. You could not adulterate water by subtracting from it, and so in like manner he contended that they could not adulterate milk by taking away. They could make it less valuable and less pure, but they could not in the strict sense say they adulterated an article by taking away from. According to the best lexicographers!

At the Antrim Petty Sessions, a milk dealer was summoned at the instance of the Guardians of the Poor of the Antrim Union for that he, on the 2nd day of March last past, at Antrim, in the County of Antrim, did sell as pure and unadulterated to the said complainants a quantity of drink-to wit, new milk, whereas same was adulterated, and not pure, contrary to the statute in that case made and provided, whereby defendant had for said offence forfeited and become liable to pay a penalty not exceeding £20, together with such costs attending proceedings and conviction as to the justices trying the same may seem reasonable.

Mr. A. O'Rorke appeared to prosecute on the part of the guardians, and Mr. Williamson appeared for the defendant.

it meant to debase, to lessen in value, to corrupt, not by | tect the public in this respect, and to see that they really abstracting from, but in every sense in which these words obtained that for which they paid. were used, by the addition of some foreign matter. He contended that they could not corrupt by taking away. In order to ascertain the correct meaning of the word adulterate, he had referred to what was the meaning of the word debase, and he found that it meant to make impure by the admixture of a baser material; he was also bound to say that the word debase meant to reduce in fineness -purity, quality, or value-but he contended that there were no such words as these made use of in the Act of Parliament. He was quite aware that his client was charged with selling milk which was "not pure," and he contended, first of all, that they had not adulterated in any way, because they had not by admixture put anything to, or altered the character of, the article which they had sold. Secondly, he contended that they had sold what they pretended to sell, viz., milk, and milk only; and there was nothing in the Act of Parliament in reference to the sale of milk, to declare whether they should sell new milk or old milk, or partially so. If a person asked for new milk, then (but he would not say then absolutely) he would be entitled to have the pure article; but he contended, under the circumstances stated, that they could not convict, unless it was proved that the article was adulterated by the admixture of some foreign substance the Act clearly implied the adding to, or putting into, and not taking away from. After a little further legal contention, the Bench decided to hear the other cases before giving their decision. Several other persons were then charged with a similar offence, viz., selling milk which was not pure, i.e., having been deprived to a certain extent of its fatty matter, or cream, by skimming. In one case, the sample analysed by Dr. Morgan was found to contain 64 parts of genuine milk and 36 parts skimmed milk.

The cases having been proved by the sworn certificate of the Analyst, the Bench retired for consultation, and after a short absence, the stipendiary said that two of these cases had been disposed of by giving the doubts which had arisen in favour of the defendants. Tbe others were seven in number; and after hearing the arguments which had been directed to the Bench by Mr. Smith on the statute and the facts, and after considering the evidence as fully as they could, they had come to the conclusion to convict the defendants in the words of the statute. The allegations in the summons was to the effect that the defendants did sell a certain article, to wit, milk, which was not pure. For that offence the Bench would convict them, following the words of the statute. No douht there was a great deal of force in the argument addressed to them on the meaning of the word adulteration. The Bench were of opinion that, if the whole expressions of the statute were taken together which had reference to "adulteration," or "not pure," they would cover the offence with which the defendants were charged. The scientific evidence must be taken as condusive, unless it was upset upon cross-examination, which had not been done. In the first case (this being a second conviction), he would be fined £10 and costs; and each of the others would be fined £5 and costs. He would also say that, in the case where a fine of £10 was imposed, the Act ordered that an advertisement should be inserted in the local papers notifying the conviction, and that would be done in the usual form. These were the first cases of this exact nature which had come before the Bench, but if any more of a similar character came before them, a much higher penalty would be inflicted. It was a most serious offence to withdraw (either by adding to or subtracting from-both were equally fraudulent) the essential property of the article sold. It was most important that the public should be protected. Parents gave their children milk, which, if pure, was the most healthy and nutritious food which could be given them; but if there were subtracted from it its fatty properties, the child could not get such nourishment as it should, and the milk was obliged to be supplemented by the addition of other food. The Bench were determined to pro

Mr. O'Rorke stated the case, and having read the summons, said that the prosecution was of a very serious nature-serious so far as it affected the health of the poor people who were supplied with the milk contracted for by the defendant. Under the Poor-Law Code the guardians of the poor had to advertise for tenders for the supply for the different articles used in the different unions, and among these was the contract for new milk. Accordingly on the 9th April, 1874, the Guardians of the Antrim Union issued the following notice or advertisement:"The Board of Guardians of this Union will, on Thursday, the 30th day of April inst., receive and consider tenders for the supply of new milk (supplemental quantity)unadulterated-at--per imperial gallon, for twelve months, ending 30th April, 1875. Probable requirements, say from 30 to 40 gallons weekly in summer, and from 60 to 80 gallons weekly in winter. All supplies must, under a penalty, indicate eight degrees of cream on the lactometer, and show a specific gravity of not less than 1'030." In pursuance of that advertisement, a tender was sent in by the present defendant, which tender was accepted, and the requisite sureties entered into for the supply of new milk from the 1st May, 1874, till the 30th April, 1875. The first Act he (Mr. O'Rorke) thought necessary to call the attention of the court to, was the 23rd and 24th Vic., chap. 84, with regard to the adulteration of food and drink. Having read the provisions under which, for adulteration, a defendant was liable to a penalty of £10, he said that the Legislature had passed more stringent measures in the Act of 35 and 36 Vic., chap. 74, which was passed in 1872. Mr. O'Rorke read the sections of this Act, and said that for adulteration the Legislature had been going on providing penalties ranging from 40s. to £10, and under the Act of 1872, the magistrates had power to impose a penalty of £20. Mr. O'Rorke read and commented on the different sections of the Acts of Parliament. The Legislature, he contended, had provided these Acts to meet such a case as the one with which this defendant stood charged, Moreover, the price paid was a very fair one, viz., Is. per gallon. However, shortly after the contract was entered into, the milk was found not to be of the stipulated quality, and a letter was written to the defendant pointing this out. Notwithstanding their remonstrance, the milk supplied by the defendant continued to be less than the standard contracted for, and on the 15th January the following letter was written :

Union Office, Antrim, 15th January, 1875. SIR,-J am instructed by the Board of Guardians to call your attention to the fact, that the new milk supplied by you of late for the use of the workhouse inmates has been ascertained-not only by instrumental tests applied, but by personal examination by the guardians themselves

to be very inferior in quality, as compared with the milk produced by the workhouse cows, and also defective as regards the standard rate of cream and specific gravity prescribed in your bond. Under these cireumstances, the guardians feel it their duty to mark their sense of this