160

Doubtful Minerals.

default by imposing the penalties set forth in respect of same in the bond from the date of last settlement-viz., 26th December, 1874. The next payment will accordingly be minus the amount of reduction in price, as per ratio prescribed. I am likewise to add that the Board of Guardians will not hesitate to take still more serious notice of any continued default in the quality of milk supplied to the workhouse.

(By order),

..

Supplies
Do.

H. C. SCOTT, Clerk of Union. 5 degs. 8 degs. Standard rate of cream, 1'022 degs. 1032 degs. Specific gravity, Mr. O'Rorke said that the guardians, finding that the amount of cream did not come up to the required standard in accordance with the bond that had been entered into from time to time, deducted from the amount of the In one account of £17 5s. account due to the defendant. account of they had deducted £4 6s. 3d., and an £20 12s. 6d. they had reduced to £14 11s. 6d. For these reductions the defendant gave a receipt, and offered no objection. The milk continuing to be below the terms of the contract, the guardians determined on sending a sample of it to Dr. Hodges for analysis. Mr. O'Rorke said, that according to the 4th section of the Act of the 23rd and 24th Vic., the productions of Dr. Hodges's certifiHe would now read Dr. cate was made evidence. Hodges's certificate.

Mr. Williamson, who appeared for the defendant, objected to the certificate. Dr. Hodges, he submitted, must appear to give evidence in the case.

Mr. O'Rorke-The Act of Parliament says he must not. Mr. Williamson would allow the certificate to be read, a note being taken of his objection.

Mr. O'Rorke then read Dr. Hodges's certificate, as follows:

Belfast, March 3, 1875. I certify that a sample of milk received by me on the 2nd instant, in a bottle sealed with the seal of Antrim Union, was adulterated by the addition of 34 per cent of water, but contained no substance injurious to health. It gave only The specific gravity of the milk was 1022. 3 per cent of cream, and contained only 7 per cent of solid matters, while pure milk of the poorest quality yields 11 per cent of solid matters.

JOHN F. HODGES, M.D., F.C.S., Public Analyst, Country Antrim. After reading Dr. Hodges's certificate, Mr. O'Rorke said he could hardly trust himself to comment on the atrocity of this case-the supply of this milk to these unfortunate He could hardly believe that any person could paupers. be found in this country having the hardihood to contract to supply a workhouse with milk, and would send in such stuff as this. He would ask the Court, after they heard the evidence, to impose as high a penalty with costs as the law permitted them to do.

The Master of the Antrim Workhouse was then examined, and said that, on the 2nd of March, he put a quantity of the milk supplied by Mr. Harper into a bottle, and sealed it. He proceeded to Belfast, and delivered this sample to Dr. Hodges.

Witness was cross-examined. No person interfered
with the sample from the time he took it until it was deli-
vered to Dr. Hodges.

The Matron was then examined as to the non-inter-
ference with the sample until it went to Dr. Hodges.
Mr. O'Rorke proved to seeing Dr. Hodges writing the
certificate.

Mr. Williamson submitted that on two grounds the
case for the prosecution must be dismissed:-First, that
the certificate of Dr. Hodges could not be relied on as
evidence, and that that gentleman should be present to
submit himself to cross-examination. Second, that the
defendant had entered into a bond with the guardians to
supply milk of a certain specific gravity, and in failing to
do so they were to impose a penalty. They had inflicted

CHEMICAL NEWS,
April 9, 1875.

penalties on the defendant, and therefore he could not be
Mr. O'Rorke replied to Mr. Williamson's arguments,
punished twice for the one offence.
after which-

The Magistrates said they had given this case a great
deal of consideration, and they were of opinion that the
Hodges's certificate was evidence, and according to that
adulteration had been proved. They decided that Dr.
certificate the milk was adulterated by the addition of
The defendant had contracted to
34 per cent of water.
supply pure milk at 1s. a gallon, and of course his profits
on that would be according to the quantity of water he
put in the milk. Under the 23rd and 24th Vict,, chap. 84,
they had come to the conclusion that the defendant
should be fined in £5, and also that he should pay £6 16s.

costs.

CORRESPONDENCE.

MANUFACTURE OF CAUSTIC SODA.

To the Editor of the Chemical News. SIR,-In the CHEMICAL NEWS, vol. xxxi., p. 145. Mr. Morrison suggests an experiment should be made with a view of depriving the lime mud of its water and re-burning I worked at it with that object without success; the it so as to use it over and over again. In the year 1840 difficulty is that it falls to powder, and the price of coal in London precluded me from treating it in a reverberatory &c., J. B. ANDERSON. furnace.-I am,

Soap Works, Southwark, April 5, 1875.

DOUBTFUL MINERALS.

To the Editor of the Chemical News. SIR,-Your correspondent T. A. R., in articles which he has communicated to your Journal, gives me more credit than is my due, and in an uncivil way brings me into collision on a point of trifling importance with the excellent Mineralogist of the British Museum, Prof. Maskelyne.

The system in mineralogical nomenclature of which he complains is not of my making. In his letter (CHEMICAL Chalcopyrite is authoritatively flashed by NEWS, vol. xxxi., p. 107) speaking of the names of species, he says:-" cablegram from Yale College," &c., "Dana all the while sheltering himself under the popular notion that the Greek language is the most approved source for names." Now, with the amount of knowledge that becomes well a teacher in science, your correspondent should not have Chalcopyrite is authoritatively flashed by typogram from thought of Dana or Yale College, but have written thus:Beudent's "Traité de Mineralogie" of 1832, Haidinger's "Handbook" of 1845, Von Kobell's "Mineralogy," and also from nearer home, even from Nicol's "Manual of MineLettsom's" British Mineralogy" of 1858, and in fact from ralogy," published at Edinburgh in 1849, from Greg and nearly all recent works on the subject, Brooke and more meaningless towanite, and their authors are all alike Miller's excepted, which strangely substituted the still blockheads. "I half blush to say it," for "yellow copper ore is a distinctive expression wherever English is spoken, is of any value in the mineral market." That would have and those who like it will continue to use it whilst the ore decided the thing, for all would have appreciated the force of the argument.

In the adoption of the scientific names of minerals used in my treatise, I have simply followed the best authorities, names from a Greek or Latin source, is the old one of and the usual law as to priority. The objection urged to uninformed minds against all scientific nomenclature. The object secured by such names is uniformity the world

April 9, 1875. 1

Chemical Notices from Foreign Sources.

over through all languages. Copper pyrites, yellow copper ore, cuivre pyriteux, cuivre jaune, kupferkies, gelferze, gelbes kupferkies, are some of the many names that were used for this species before the science had accepted of chalcopyrite for universal use. Works on mineralogy give the common names as well as the systematic; and no mineralogist is ever disposed to quarrel with the miner, or any other person, for saying, as often as he chooses, "yellow copper ore."--I am, &c.,

Newhaven, Conn., March 23, 1875.

JAMES D. DANA.

161

liberate about the same amount of heat, both when dissolved in water and when they react on potash. The two oxidation, liberate also quaniities of heat, which differ little valerianic acids, that from valerian and that obtained by in presence of water.

sity for Calculation.-M. Lowe.-Two thermometers, on the same stand, are fitted with a graphic table, which "Hygrodeik" Psychrometer, Obviating all Necespermits the observer to find rapidly the evaluation which he requires.

New Burette.-M. A. Pinchon-The Pinchon burette CHEMICAL NOTICES FROM FOREIGN upon a caoutchouc receiver adapted to a flexible tube, and is fixed almost horizontally upon two supports. Air is forced gradually in at the top by means of a screw acting

SOURCES.

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

Comptes Rendus Hebdomadaires des Seances de l'Academie
des Sciences, No. 9, March 1, 1875.
Certain Problems of Molecular Mechanics.-M.
Berthelot. The author describes the butyrate of soda as
the starting-point of his considerations, and examines the
heat liberated by the anhydrous salt and its hydrates
during solution, the successive states of the dissolved
salt, and the formation of crystalline hydrates.

Experiments on the Artificial Imitation of Native
Magneto-Polar Platinum.-M. Daubrée.-It is well
known that certain specimens of native platinum not only
act upon the magnetic needle, but are themselves polar,
in the manner of true magnets.
magnets, according to M. de Koksharrow, are capable of
These native platinum
withdrawing a considerable quantity of ferruginous grains
from the auriferous sand of the Ural after an ordinary load-
stone ceases to have any effect. A similar magneto-polar
platinum was produced by fusing the metal with a small
quantity of iron.

On Magnetism.-Th. du Moncel.-The property of magnetism of not readily penetrating into the whole of a magnetic mass explains easily the law of the proportionality of the attractive forces of electro-magnets to the diameters of their nuclei. their surface rather than with their mass, and explains This law is in relation with the great power which the author has developed in a tubular electro-magnet with a nucleus 10 centimetres in diameter, a tube I centimetre in thickness, and with arms 30 centimetres in length. This electro-magnet, with a single Bunsen element, and with only 482 folds of wire of 4 m.m. diameter, exerted an attractive force of 160 kilos. The force was slightly increased with 5 Bunsen elements, but it was not further perceptibly increased even with 20, because the magnetic mass was no longer in relation with the electric energy.

the liquid is forced out by drops.

Moniteur Scientifique, du Dr. Quesneville,
January, 1875.

Process Employed in the Royal Works of Freiburg for Freeing Sulphuric Acid from Arsenic.-M. F. Bode. -A very valuable paper, which, however, cannot be made intelligible without numerous illustrations.

by the Electrolytic Process.-Taken from the Bulletin Determination of Copper and certain other Metals de la Societe d'Encouragement.

Researches on the Methods of Determining Phosphoric Acid, conducted at the Agricultural Station at Halle, on the Saale.-O. Abesser, W. Jani, and M. gravimetric methods are concerned, may be summed up Maercker. The results of the authors, as far as the as follows:-For precipitation with molybdate of ammonia should be from 50 to 100 c.c. a quantity of the sample is taken, containing from o'1 to 02 grm. of phosphoric acid. The bulk of the liquid The molybdic solution is

prepared according to Fresenius, by dissolving 150 grms.
this solution into 1 litre of pure nitric acid. The quantity
molybdate of ammonia in 1 litre of water, and pouring
As the ammonium molybdate of commerce contains about
of solution used should be such, that for 1 part of phos-
phoric acid there may be about 50 parts of molybdic acid.
solution are required for o'i grm. of phosphoric acid. A
large excess of molybdic acid is not a direct obstacle to
83 per cent of molybdic acid, about 100 c.c. of the above
to be desired, since a certain quantity of free molybdic
the exactitude of the operation, but it is a hindrance not
precipitation of the phosphoric acid to let the mixture
acid is almost always deposited, which does not easily re-
dissolve in ammonia. It is sufficient for the complete
digest for four to six hours at 50° C. After cooling, the
yellow precipitate is filtered, and washed with a mixture
parts. The yellow precipitate of phospho-molybdate of
of solution of molybdate of ammonia and water, equal
monia, I part of commercial ammonia to 3 of water.
ammonia is dissolved upon the filter with dilute hot am-
is necessary to neutralise the excess of ammonia with
It

Purple Colouring-Matter derived from Cyanogen.-hydrochloric acid. Chloride of ammonium is formed, an
M. G. Bong. Already noticed.

Determination of Boracic Acid, and its Separation when found along with Silica and Fluorine.-M. A. Ditte. Already noticed.

Reciprocal Displacement of the Volatile Fatty

Acids.-M. H. Lescœur.

Calculation of the Moments of Maximum Inertia of the Molecules of the Chlorinated Derivatives of Toluene.-M. G. Hinrichs.-A mathematical paper; not adapted for abstraction.

Study of the Amounts of Heat Liberated in the Formation of the Potash-Salts of Certain Acids of the Fatty Series.-M. W. Louguinine. The author draws the following conclusions:-That the amounts of heat disengaged in the formation of the potash-salts of acids of the fatty series seems to increase as we ascend the homologous series; the two isomeric butyric acids

ΙΙΟ

cipitate should be dissolved in as little ammonia as
excess of which is not desirable; hence, the yellow pre-
possible. Hydrochloric acid is added to the ammoniacal
the magnesian mixture, for, if hot, basic salts of magnesia
solution as long as the precipitate formed re-dissolves
quickly. The liquid must then be cooled before adding
the result. The magnesian mixture is prepared with
are sometimes thrown down, and increase the weight of
grms. of crystalline chloride of magnesium,
140 chloride of ammonium, 700 of liquid ammonia, and
acid, we require 10 c.c. of this mixture. The presence
1300 of water.
of soluble magnesic salts diminishes the solubility of the
To precipitate or grm. of phosphoric
double phosphate of magnesia and ammenia.
adding the magnesian mixture, we pour in one-third of
its volume of concentrated liquid ammonia. The total
After
bulk of the liquid should not exceed from 100 to 110 c.c.
In three or four hours the precipitate is ready for filtration.

162

Chemical Notices from Foreign Sources.

|

April 9, 1875. phosphate at 124 per cent (of which 20 grms. form 1 litre of solution); add 10 c.c. of acetate of soda, and run in the uranic liquid into the cold solution till the reaction begins to appear. Then boil, and try the reaction of ferrocyanide of potassium with a drop of the liquid upon a porcelain plate. To have the final reaction very distinct, dry pulverised ferrocyanide of potassium must be used. A quite freshly prepared solution also gives a distinct and regular reaction, but an old one does not. The solution of superphosphate is determined in the manner just described, in 50 c.c. With very rich superphosphates the final reaction loses somewhat of its distinctness, from the uranic phosphate which is abundantly precipitated. To avoid this inconvenience, take 25 c.c. in place of 50, and dilute with an equal volume of water.

Losses of Nitric Acid in the Manufacture of Sulphuric Acid.-M. W. Hasenbach.-This paper has been already noticed.

by Water.-M. A. Ditte.-Noticed elsewhere. Researches on the Decomposition of Certain Salts Applications of Indigo.-M. A. Schultz.-Reserved for insertion in full.

Extract of Indigo.-M. P. Hubert.-It is well known that extract of indigo is sodic sulphindigotate, precipitated from a sulphuric solution of indigo by means of soda crystals and chloride of sodium. The product, after being washed more or less perfectly, often still contains a greenish matter, which is visible if a little of the extract is spread out on filter-paper. To assay a sample, two grms. are dried in a stove. The loss in weight shows the quantity of water present. The residue is ignited, and weighed to find the mineral matter. The amount of indigo is shown by the difference. According to M. Girardin, the extracts of commerce are divided into single, double, and treble, according to their strength. The following is the mean composition :

Water.

Indigo.

The precipitate is washed on the filter with dilute ammonia (31) until chlorine can no longer be detected in the filtrate. No subsequent correction is needful. When dry, the precipitate is removed from the filter (which is burnt separately). The flame must be feeble at first, and be gradually increased. It is finally ignited with the gas blowpipe. Brief Description of the Systematic Course of the Volumetric Analysis of a Superphosphate.-20 grms. of the sample are treated with water in a mortar. The lumps are broken up without pressing them strongly, and the whole poured into a litre-flask, which is filled with water up to the mark, closed with a stopper, shaken briskly for some minutes, and filtered immediately. This method of extraction is not applicable to superphosphates prepared from Lahn phosphorite, which must be extracted by washing on the filter (see Fresenius, Neubauer, and Luck). The filtrate is examined with acetate of sodium to find if there is a precipitate of phosphate of iron. If there is a precipitate, 200 c.c. of the filtrate are mixed with 50 c.c. of a solution containing per litre 100 grms. of crystalline acetate of soda, 100 grms. of concentrated acetic acid, equivalent to 30 or 40 grms. of glacial acid. Filter to separate the precipitate, wash on the filter three or four times in boiling water, ignite in a platinum crucible, and calculate 0'47 of the final weight as phosphoric acid. The liquid filtered from the precipitate of phosphate of iron is then titrated; 50 c.c. of this represent 40 c.c. of the original solution. If there is no precipitate of phosphate of iron, titrate 50 c.c. with uranium solution, after the additton of 10 c.c. of a mixture of acetate of soda and acetic acid. The acetate of soda and free acetic acid are not without influence upon the appearance of the final reaction of uranium with ferrocyanide of potassium. It is therefore necessary in titrating the uranium solution with phosphate of lime to add the above mixture in a quantity exactly equal to that used for superphosphates. Titration of the Uranic Solution.-500 grms. of nitrate or acetate of uranium (crystalline) diluted with water to the bulk of 14 litres, yield a solution, of which I c.c. precipitates about 5 milligrms. of phosphoric acid. Nevertheless it is prudent to take an excess of 25 to 30 grms. of the uranic salt, since there remains almost invariably a deposit of insoluble basic salts. As the nitrate always contains free nitric acid we add, to neutralise it, acetate of soda in the proportion of 50 grms. to 500 grms. of the uranic salt. To the acetate we add, per 500 grms., 50 to 100 grms. of concentrated acetic acid, which renders the solution of the salt more stable. It is needful to let the uranic solution stand some days before filtering, since the deposition of the basic salt does not take place imme-a similar solution of a standard quality. The shades must diately. It is best to standardise, not with sodic phosphate, but with an acid calcic phosphate; thus reproducing, as far as possible, the circumstances to be dealt with in the analysis of superphosphates. To prepare the liquid for titrating the uranic salt, digest 5'5 grms. of tribasic phosphate of lime with dilute sulphuric acid, containing 2.85 to 2.90 grms. of SO3. The authors employ for this purpose the dilute sulphuric acid serving for the determination of nitrogen by Will and Varrentrapp's method. After digestion the mass is taken up with water, and diluted to 1 litre. It is then filtered to remove sulphate of lime, and the small quantity of basic phosphate of lime which has not been dissolved. It is more convenient, and quite as exact, to dissolve the pure basic calcic phosphate in a slight excess of nitric acid, and to determine the amount of phosphoric acid contained in the liquid by adding ammonia, and igniting the precipitate. It must not be forgotten that tribasic phosphate of lime, though it appears dry, still contains 10 to 15 per cent of moisture, account of which must be taken in preparing the solution for standardising. 50 c.c. of this liquid contain about 0125 grm. of phosphoric acid, and are precipitated by 25 c.c. of the uranic solution prepared as above directed. For the titration itself take 50 c.c. of the solution, i.e., as much phosphoric as there is in the solution of a super

Single extract
Double extract

Treble extract

Salts.

89.0

4'96

5'7

85'0

IO 20

4.8

73'7

12'40

13'9

The following results have been obtained with commercial samples at Rheims :

Water
Indigo
Salts

.. 845 897 82.65 9115 88.6 87.2 10.6 5.6 9'55 8.2 6'05 8.4 4'7 4'7 7.80 2.85 5'2 But the dyer has still to make comparative trials with a solution containing 1 grm. per litre of the sample, and with

of equal weight must be dyed, sulphate of soda and sulbe compared in the colorimeter; two swatches of merino phuric acid having been previously added, and a decolourisation assay must be made with a standard solution of potassic permanganate, containing o'5 grm. of the crystalline salt per litre.

Influence of the Presence of Nitrogen in Textile Fibres on the Direct Fixation of the Aniline Colours. M. E. Jacquemin. The author shows that gun-cotton takes up magenta in the same manner as do silk and wool. On the other hand, oxamide could not be dyed in a solution of magenta at 80°.

Liebig's Annalen der Chemie und Pharmacie.
Band 175, Heft 3, Jan. 23, 1875.

On Amidoid Derivatives of Hydroxylamin.-This paper is divided into five sections, namely:-On the Formation of Diphenyl-urea from Dibenzhydroxamic Acid, and the Transformation of Benzoic Acid into Aniline, by H. Rotermund; On the Structural Formula of Hydroxylamin and its Amidoid Derivatives, by W. Lossen; On the Distillation of Dihydroxamic Acids, by F. Pieschel; On the Methods of Replacing the Carboxylgroup of Aromatic Acids by the Amid-group, by W.

April 9, 1875.

Lossen; and On the Ethers of Dihydroxamic Acids, by E. Eiseler. None of these essays are susceptible of useful abstraction.

Properties of Normal Sulphobutylic Acid, and its Salts.-N. Grabowsky.-The author describes the pure normal acid, CH3CH2CH2CH2SO2OH, as a thick syrupy liquid, in which no trace of crystallisation appears. It is readily soluble in water and alcohol, but more sparingly in ether. It readily forms salts with carbonates and The soda salt, C4H,SO,Na, forms hydrated oxides. tabular crystals free from crystalline water, readily solu

The baryta salt, ble in water and boiling alcohol. (CH,SO3)2Ba+H2O forms large foliaceous crystals which on exposure to dry air lose their crystalline water, but without any alteration in form. The author has also produced and examined the lime, lead, copper, and silver salts.

Testing Fibres in Cloth.-Could you kindly inform us if there is any means of testing cloth made with a mixture of cows' hair, goats' hair, and wool, so as to demonstrate what quantity of each it contains, or whether there is any wool at all in it? We want to know how to tell the difference.-R. H. S.

Anthracene.-Having recently been engaged in the manufacture of anthracene, I am anxious to gain all the information on that subject I possibly can obtain. Would you kindly inform me of the best works on that particular source of manufacture, or of tar in general, and its products?-W. F.

Now Ready, Second Edition, price 3s. 6d.,
MANIPULATION;

MICROSCOPICAL

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action Action of Nitric Acid upon Normal Butyl-sulphide. HOW TO MAKE MONEY BY PATENTS.

-N. Grabowsky.-The author obtains as the result of the reaction butyl-sulphon, (C4H9)2SO2. He concludes that as a general law thio-ethers with normal radicals are

BARLOW & CO., 23, Southampton Buildings, W.C. respecting Patents for Inventions."

able to form both oxides and sulphones, but those with Chem

abnormal and mixed radicals oxides only.

Synthesis of Diethyl-Carbinol, a New Isomer of Amylic Alcohol.-G. Wagner and Alex. Saytzeff.-The authors obtained this compound by adding to a mixture of 1 molecule of formic ether and 4 molecules of iodide of ethyl a little zinc-sodium, and so much dry, finely granulated zinc that it may just rise above the surface of the liquid.

New Synthesis of Secondary Butylic Alcohol.-J. Kanownikoff and Alex. Saytzeff.-The authors obtained this compound by the reaction of 1 molecule formic ether with 1 molecule iodide of ethyl and I molecule iodide of methyl, with the addition of zinc and zinc-sodium, as in the former paper.

An Improved Apparatus for Fractionated Distillation.-G. Glinsky. This paper is not intelligible without the accompanying illustration.

author

Composition of the Platinum Compound of Dehydro-triaceton-amin.-W. Heintz.-The demonstrates that this body is not identical with Städeler's acetonin-platin-chloride.

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NOTES AND QUERIES.

Beer.-Would any of your readers inform me where any systematic analysis of beer (that can be relied on) is described, especially concerning the detection of the bitter principles used for adulteration?M.B

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