CHEMICAL NEWS,

June 21, 1862.

349

The effect of surrounding the flame of an ordinary oillamp with a receptacle containing cold liquid, would be likely at first to interfere so much with the proper motion of the ascending current of air as to give rise to the production of a sinoky flame, and to the deposition of considerable quantities of carbon upon the cold metallic surface next the flame.

soap.

CORRESPONDENCE.

Blue Ammonia Vapours.

To the Editor of the CHEMICAL NEWS. SIR, I hope that the controversy going on about Mr. Williams's blue vapours will now be satisfactorily settled to all who, like you, derive their chemical experience from must say, however, that when a boy I have often seen the laboratory, and not from dunghill experiments. I bluish vapours rise from dunghills, immaterial whether close by or far from any chemical works or factories, and his back to the light when he applies his strong liquor how such a vapour would appear to Mr. Williams, with ammonia, must be apparent to all, even if they had never heard of blue ammoniacal vapours or

London, June 14.

BLUE MOONSHINE.

To the Editor of the CHEMICAL NEWS.

SIR,-I am very glad to see that Mr. Williams has accepted your invitation to explain the appearance of his "bluish

1862.

in the construction of lockets and other articles of jewellery."

1453. Richard Archibald Brooman, Fleet Street, London, "An improved method of, and apparatus for, the production of photographic and stereoscopic portraits and pictures."-A communication from Leon Farrenc, Rue St. Quentin, Paris.

14 55. Henry Deacon, Appleton House, Appleton, Lancashire, "Improvements in the manufacture and production of certain colours, and in the apparatus employed therein."

1484. Amand Athanase Lamiable, South Street, Finsbury, London, " Improvements in cementing cast and

wrought iron to obtain cast steel."

1496. Christopher Binks, Parliament Street, Westminster, Middlesex, " Improved methods of obtaining oxygen and chlorine gases.'

1528. William Petrie, Charlton, Kent, "Improvements in vessels for boiling chemical products, as sulphuric acid, and in apparatus for indicating the degree of concentration and temperature of such products in the boiler, which apparatus is applicable to other pyrometric purposes."Petition recorded May 20, 1862.

1550. Henry Cook, Manchester, "Improvements in electric batteries."-A communication from Jean Minollto, Turin, Italy.

Notices to Proceed.

66

3229. Jabez Jones, Liverpool, Improvements in the manufacture of lead, tin, and other metals, or amalgamation of metals of a like nature fusible at a low temperature into sheets of any thickness or length, and in the apparatus connected therewith.'

735. Brereton Todd, Bissoe and Perran Smelting Works, near Falmouth, Cornwall, "Improvements in the manufacture of antimony and oxide of antimony." •

1030. Henry Deacon, Appleton House, Appleton, Lancashire, "Improvements in the manufacture of caustic soda."-Petition recorded April 10, 1862.

1244. William Taylor Glidden, Massachusetts, U.S., "A new and useful mode of restoring phosphatic guano.' -A communication from Louis Harper Brooklyn, New York, U.S.-Petition recorded April 29, 1862.

228. Rudolph Bodmer and William Wilson, Newport, Monmouthshire, "Improvements in the process of manu

reputation that he should do so; and now perhaps it is simply an error in description. made quite clear that what provoked your remarks is I tried several experiments after reading your report of the trial, and I could in could call bluish vapours. no way get what, by any stretch of the imagination, I Since then I have tried those suggested by Mr. Williams in his letter, with no better

success. It is true that when I set a dish of ammonia

and of hydrochloric acid side by side in the open air, and might, if I had never seen the same thing in the laborawatched the vapour form against a bright blue sky, I tory, have called the vapour bluish.

Mr. Williams's error lies in asserting that bluish vapours acid, just as a sky-blue mixture is a proof of the presence from ammonia are proofs of the presence of hydrochloric of water with milk,

of chemical" sweep like a destroying angel over his crops. I can imagine a farmer looking blue as he sees a "waif He may, indeed, get blue vapours; but under no circumtwo gases in question to look other than white. stances can I imagine the vapour from the contact of the vapour may present a different appearance according as it is dense or attenuated; but white it is, and must be. I am, &c.

June 17.

MISCELLANEOUS.

The

F. C. S.

Note on Thallium, by WILLIAM CROOKES. SINCE my preliminary announcements of the discovery of this element, I have purposely avoided publishing the various results of experiments week by week as they were obtained, my object being to prepare, at some future time, a paper on the subject, which might be deemed worthy of a place in the "Transactions" of the Royal Society. Within the last week, however, it has come to my knowledge that a continental chemist has recently had the good fortune to discover a plentiful source of this element, and has prepared the metal and several of its compounds. This has induced me to collect together into one paper all the facts which I have as yet discovered. It will probably be published in an early Number of the CHEMICAL NEWS; and in the mean time, both for the purpose of placing the dates on record, and of showing that though silent I have not been idle during the past year, I publish the following letter from a good friend whose assistance in this matter has been of

more material service to me than a perusal of his letter would lead the reader to imagine :

"5, New Cavendish Street, London, W. "June 16, 1862.

·

"My Dear Sir,-I well remember paying you a visit in January last to see the thallium' you had then got into a more definite shape. As I had seen its reaction in the spectroscope many months before, and was much interested in the remarkable discovery, I felt great pleasure in watching the progress you had then made in the investigation.

"You had several compounds of the body, including, if I remember rightly, the sulphide (of which I possess a specimen), and the oxide which you had obtained in crystals. The quantity of material you had, however, was but small; and it was only by exercising the greatest amount of ingenuity that you were able to demonstrate the nature of its compounds.

"The most interesting point, I well remember, was the metal itself, deposited by means of a weak galvanic current,-first on a bar of copper, where it presented a coherent metallic appearance, of dark colour, but which, when freshly scraped with a knife, gave a coloured metal similar to lead. You also had a larger quantity precipitating on platinum in the spongy form, which compressed, gave metallic lustre; and when tried in the spectroscope, gave the green line magnificently.

46

Very shortly after I met our friend, Mr. E. O. Brown, of the Chemical Department, Woolwich, who had been testing some of your results, and I was much interested to hear so many particulars as to its chemical cha racter and reactions. Its precipitation as a subsalt or subchloride by water, and its iodide and oxide, pointed out its true metallic character; if, indeed, any doubt could have existed in my mind previously upon the subject.

"I am sorry I was prevented from fulfilling the promise I made you in January, to work the sulphur containing the thallium for you on a large scale, and so get out sufficient for the purposes of a strict chemical investigation. This I have been prevented from doing from unforeseen circumstances, as you are aware; and I must say I am very much astonished that with your means you have been able to make out the large number of facts you already know respecting the element, particularly when we consider that the mineral you had to work with did not probably contain more than two or three grains in the pound. "I remain, yours, very truly,

"W. Crookes, Esq., F.C.S." "John Williams. The following paragraph on this subject appeared in the London Review for the 14th inst. :

“Thallium. — Mr. Crookes, whose discovery eighteen months ago of this new element by the spectroscope we have already announced, has since prepared numerous compounds of it, some samples of which are to be seen in the Chemical department of the International Exhibition. We were shown some time since a specimen in its pure metallic state, obtained by Mr. Crookes, but as no detailed statement of its characters, nor of the nature and actions of its salts, have been as yet published, although a short abstract has been displayed with the specimens since the opening of the Exhibition, it may be interesting to our readers to know what this new element--the only one discovered by an English chemist since Sir Humphrey Davy's detection of the metallic bases of the alkalies-is like. is a dense, heavy, rather lustreless metal, very like lead, to which metal it is also very similar in its physical properties, but is a trifle heavier, and tarnishes perhaps a little quicker. Its colour, however, is not identical. In chemical properties it is similar to mercury, lead, and bismuth. Mr. Crookes is continuing his researches, and we are glad to state that the Royal Society has voted him a grant of 50l. towards the expenses of these costly investigations."

It

NEWS

Ozone.—In a letter to Professor Faraday, Schönbein writes:-"After many fruitless attempts at isolating ozone from an ozonide, I have at last succeeded in performing that exploit; and have also found out simple tests for distinguishing with the greatest ease ozone from its antipode, antozone.' As to the production of ozone by purely chemical means, the whole secret consists in dissolving pure manganate of potash in pure oil of vitriol, and introducing into the green solution pure peroxide of barium, when ozone, mixed with common oxygen, will make its appearance, as you may easily perceive by your nose and other tests. By means of the ozone so prepared, I have rapidly oxidized silver at the temperature of 20° C., and by inhaling it produced a capital 'catarrh.'"-Philosophical Magazine.

Chemical International Banquet.-The English chemists entertained the chemical jurors and other distinguished chemists at present visiting London, at a banquet given at the Trafalgar, Greenwich, on Tuesday evening last. The chair was taken by Dr. Hofmann, President of the Chemical Society, and the company consisted, among others, of Professor Faraday, the Master of the Mint, M. Balard, M. Pelouze, Professor Schrötter, Dr. Percy, Professor Fehling, Mr. Walter Crum, Professor Daubeny, Professor Wurtz, Dr. De Mussy, Professor Regnault, M. Peligot, Professor Williamson, Professor Baumbaner, Professor Frankland, Le Viscount de Villa Maier, Dr. Odling, Dr. Stenhouse, Mr. Grove, Mr. Warren De la Rue, M. Woskrescenski, M. Stas, Professor W. A. Miller, Baron Thénard, Dr. Atkinson, Mr. G. Wilson, Mr. Maskelyne, M. Persoz, Professor Forchammer, Professor Brodie, Mr. D. Campbell, M. Daubrée, Mr. Smee, M. Barres will, Mr. Attfield, Professor AnderProfessor Roscoe, Mr. Young, Professor Piria, Dr. Müller, Professor Sobrero, Professor Mennier, Professor F. C. Calvert, Mr. Abel, Dr. Normandy, Professor Lourenço, Professor Chandelon, Professor Redwood, Mr. Morson, Mr. Perkin, Dr. Noad, M. Kuhnheim, Dr. Buckton, Dr. Gilbert, Dr. Lieben, Dr. Price, M. Barral, Mr. Hiesch, Professor Herapath, Dr. Marcet, Dr. Longstaff, Mr. Hanbury, Mr. Field, Dr. Bence Jones, Dr. Bernays, Mr. J. P. Gassiot, Dr. Gladstone, Dr. Letheby, Dr. Lyon Playfair, Mr. Porret, Mr. T. Taylor, Mr. Warrington, Dr. Dexter, Professor Fremy, M. Hulot, &c.

son,

S.-Dilute hydrochloric acid will effectually remove ink stains from paper. The paper will not be injured if the acid be thoroughly washed out of it immediately after it has done its work.

A. B. O'Neill's treatise on Dyeing is the best with which we are acquainted.

A. Wilkinson-A porous surface moistened with water containing a very small quantity of mineral acid will probably answer your requirements.

Bronze for Rifle Barrels-Rifleman.-The following is the composition of the acid solution generally used by armoury-serjeants at British stations for the purpose of bronzing the iron barrels of rifled small

arms:

SCIENTIFIC AND ANALYTICAL CHEMISTRY.

99'95

II.

95'90

95'78

4:06

4'10

99'96 99'88

Theory. 95.86

4'14

100'00

The crystals are anhydrous and yield results closely corresponding with the formula 9HgCl,NH,Cl. They may be formed by dissolving 25 parts of chloride of mercury and one part of chloride of ammonium in hot water, with the aid of a little hydrochloric acid, and crystallising. No. III. is an analysis of the salt so prepared. It crystallises in forms of the oblique system, has a specific gravity of 306, dissolves readily in water, but is decomposed, the solution depositing crystals of chloride of mercury, unless a little hydrochloric acid be added. A solution of this salt gives a yellow precipitate with potash, but does not evolve ammonia, even when boiled; with bichloride of platinum, when added in considerable excess, it gives a yellow precipitate.

If an excess of hydrochloric acid be added to a solution of the above salt, it deposits on evaporation long acicular crystals, containing,—

Chloride of mercury Chloride of ammonium Water

Theory.

which corresponds with the formula 3HgCl,NH,Cl4HO. They are permanent in the air, and very soluble in water. If three equivalents of chloride of mercury one equivalent of chloride of ammonium be dissolved in water, and the solution evaporated, on cooling it becomes almost solid, from the formation of a mass of very small acicular crystals, which dissolve again on the slightest elevation of temperature. Some of the crystals dried at 100° C. gave:

But the water they contain appears to be variable, the loss at 100° C. being on different occasions 2'53, 4*67, 4.88, and 5.02 per cent.

TECHNICAL CHEMISTRY.

On the Preparation of Pure Caustic Soda on the Large Scale, by Dr. PH. PAULI, of the Union Alkali Works, St. Helens, Lancashire.

THREE tons of commercial caustic soda, containing excess of water, alumina, and all the impurities which commonly occur in this substance, are fused in a castiron pot. During the evaporation nearly all the carbonate, and by far the larger quantity of the other salts, separate out on the surface as a scum, and can be easily removed. The liquid mass is then heated to dull redness, and kept at that temperature during the night. In the morning the mass appears perfectly transparent, the sides and bottom of the vessel being coated with cauliflower-shaped masses of crystals consisting of silicate of alumina, with chloride and sulphate of sodium and a little lime. The clear fused liquid is ladled off from these crystals, and when cooled is ready for use.

The soda thus obtained is perfectly free from alumina; a small quantity of the soda was fused in a platinum crucible, and some pure alumina added. This remained undissolved in the fused mass, swimming about like a precipitate in the red-hot liquid. On cooling, water was added to this fused mass, and the alumina was found to dissolve completely. If the commercial soda contains oxide of iron, this also separates out completely during the process of fusion. Lime, on the other hand, is dis solved in large quantities by the caustic soda, but it is completely separated by solution in water. The caustic soda prepared in this way is hard and brittle, and can be easily obtained as a fine powder by attrition in an iron mortar. It contains only a trace of carbonate of sodium. This product, which will doubtless prove a valuable reagent in chemical laboratories, is now prepared on a large scale by Messrs. Evans and McBryde, Union Alkali Works, St. Helens, Lancashire.

Aluminium.—Owing to the length of Mr. M'Gauley's important article on Aluminium, commenced last week, we

were compelled to defer the conclusion to a subsequent Number; and so much space being this week occupied by

our Index, we are again obliged to omit several articles which we have in type. We therefore feel that it is only right to state at once, what we intended mentioning at the conclusion-that the above article was extracted from the Intellectual Observer, one of the best as well as most popular of the monthly magazines. We shall take an early opportunity of giving a more extended notice of this serial; and in the mean time can refer our readers to the extract already given as a sample of the sterling character of the intellectual food provided for its readers by the publishers, Messrs. Groombridge and Co.

PHARMACY, TOXICOLOGY, &c.

On the Colour-tests of Strychnia, as Modified by the Presence of Morphia, by ROBERT P. THOMAS, M.D., Professor of Materia Medica in the Philadelphia College of Pharmacy.

(Continued from page 342.) Experiment 2 was an exact duplicate of the first in all of the varied strengths of the two articles, with the simple difference of having them in solution in water acidulated with acetic acid, instead of being in the solid form.

To obviate the necessity of a subsequent concentration of the solutions by heat, the salts or alkaloids were macerated in small measures only, of acidulated water, and to each solution an excess of a solution of potassa was added, and then an equal measure of chloroform, which dissolved out the strychnia, and subsequently yielded it as a filmy deposit in a capsule, by spontaneous evaporaWith sulphuric acid and bichromate of potassa, the proper test-colour was manifested by the deposit in each

tion.

case.

In my opinion, these experiments determine conclu sively that strychnia can be 'detected by colour-tests, even when masked by morphia-either as the alkaloid or one of the salts-to the extent of twenty times its own weight.

But the question raised is not so much whether strychnia will be masked by pure morphia or its salts, uncontaminated with anything else, as whether morphia in the presence of organic mixtures has the power of preventing the recognition of strychnia by the usual colour-tests. To determine this latter point, my attention was directed, in the next instance, to the devisal of a simple and practical method, by which its recognition could be secured. Upon reflection, I concluded that the most feasible plan of overcoming the difficulty would be to separate the poison entirely from the organic mass, by chemical agents and solvents.

After careful investigation and repeated trials, I selected as the agents the three fluids used in experiment 2. These fluids can always be obtained at trifling cost, of easily ascertained strength, and of known purity. They are,-1. Acetic acid, of the specific gravity 1041. 2. A solution of one drachm of caustic potassa in a fluid ounce of water. And, 3. Chloroform.

Acetic acid was chosen, because, when in excess, it has the property of dissolving all of the ordinary salts, both of morphia and strychnia, as well as their tannates, which are generally described as being insoluble; and, therefore, by treating an organic mass containing these alkaloids with this acid, we would obtain a solution of the acetates of morphia and strychnia.

The solution of caustic potassa was selected for several reasons. For instance, in neutralising the acetic acid, it forms a soluble salt of potassa, thereby getting rid of the acid when we are done with it. It saponifies the fats of the organic materials; it decomposes their sugars; and it dissolves morphia, but does not dissolve strychnia, thus enabling us to separate the one alkaloid from the other by its agency.

Chloroform was resorted to for its solvent and volatile properties. Thus 100 parts of it, according to M. Pettenkoffer, at ordinary temperatures dissolve 2016 parts of strychnia and only 0.57 parts of morphia. A fluid-drachm of it, holding the strychnia in solution, will evaporate

spontaneously in a few minutes if placed upon a saucer or plate.

As the solution of potassa dissolves morphia and rejects strychnia, while chloroform has the reverse promorphia, it must be evident that the conjoint use of perty of taking up the strychnia and rejecting the these fluids would effect an entire separation of the two alkaloids the morphia being held by the potassa and the strychnia by the chloroform.

Another important practical advantage in the use of these fluids is found in their different specific gravities. The chloroform, being the heavier, sinks to the bottom of the vessel containing them, and thus a separation is easily accomplished.

The eliminating properties of the three fluids were determined in the following way:

Experiment 3.-One grain of strychnia and three grains of opium were macerated for three days in a mixture of equal measures of acetic acid and water; then filtered, and to the clear liquid equal bulks of the caustic solution and chloroform were added, and the whole well shaken together. Upon subsidence the chloroform was separated, and a part of it evaporated on a plate. The deposit thus obtained was treated with sulphuric acid and the bichromate of potassa, in the manner before described, when a fine play of test colours resulted.

In this and the subsequent experiments care was always observed to have the caustic solution in sufficient excess over the acetic acid to dissolve the morphia, and leave the solution alkaline to test paper.

Having thus determined the practicability of regaining the strychnia in a separate state from a solution in which it had been associated with the various alkaloids of opium, I proceeded, in the next instance, to the examination of its relations to morphia in the presence of organic matter. For this purpose a nutritive mass was prepared as the representative of the contents of a man's stomach, if death should occur soon after a meal. The mass consisted of two ounces of minced meat,-such as is used for pies, and containing meat, suet, various dried fruits, cider, spices, and a little brandy-two ounces of bread, a portion of salt, pepper, and vinegar, and two fluid-ounces of a strong infusion of coffee, well sweetened. In other words, an association of the nitrogenous and non-nitrogenous elements of food, with spices, alcohol, tannic acid, and caffein. To this mass one grain of strychnia and five grains of morphia, which had been previously well triturated together and dissolved in a mixture consisting of one fluid-drachm of vinegar and fifteen fluid-drachms of water, were now added, and the whole carefully mixed. The mixture was set aside for twenty-four hours to permit the alkaloids to permeate the entire mass, and it was then divided into four equal parts, each part being made the subject of an experiment, as follows:

Experiment 4-The first portion, containing one quarter of a grain of strychnia and one and a-quarter grains of morphia, was treated with f5ij. of acetic acid (1041), and fživ. of water. The mixture having been allowed to stand for sixty hours, was raised to the boiling heat, and ebullition was maintained fifteen minutes. Having been strained and filtered, equal quantities of chloroform and the caustic solution were added to the filtered liquid. The whole were well agitated together, and after subsidence the chloroform was separated and evaporated. Upon treating the deposit with sulphuric acid and ferricyanuret of potassium, the distinctive play of colours appeared.

This experiment proves that strychnia is not decom.

CHEMICAL NEWS, June 28, 1862.

posed by a heat of 212°, maintained for a short period, even though morphia and organic matter be present. The elevated temperature is objectionable, however, from the large amount of starchy matter dissolved by the boiling water, which clogs the subsequent steps of the process.

Experiment 5.-The second portion, containing the same amount of alkaloids as the preceding, was macerated twelve hours in fij. of acetic acid and f3ij. of water, then strained with pressure, and filtered. The resulting liquid was treated with equal measures of chloroform and the caustic solution. The deposit from the evaporated chloroform yielded the proper colours with the test agents.

This, like many subsequent experiments, proves that it is unnecessary to employ heat; acetic acid, mixed with an equal measure of cold water, being amply sufficient for the extraction of alkaloids from an organic mass.

Experiment 6.-The third portion was macerated, like the preceding, for twelve hours, in acetic acid diluted, and then pressed and filtered. The resulting liquid was placed in a capsule before the register of an ordinary house furnace, and was evaporated to a syrupy consistence by the warm air passing over its surface. To this the chloroform and the solution of caustic potassa, in equal measures, were applied, and all well mixed. The separated chloroform yielded a deposit which was proved to be strychnia by the test agents.

By this experiment we learn that a solution containing both alkaloids in contact with organic matters may be evaporated by a moderate heat almost to a solid consistence without their decomposition.

Experiment 7.-The fourth portion was set aside for twelve days in a room having a temperature of 68° to 70°. At the expiration of this period the mass had become sour and offensive, and was spotted with crusts of mould. It was then macerated for twelve hours in a mixture of f3ss. of acetic acid and f3jss. of water; after which it was strained, filtered, and evaporated like the preceding to the consistence of syrup, by the passage of a current of warm air over the surface. As the resultant liquid was intensely sour as well as bitter, I added two measures of the caustic solution and one of chloroform, and agitated the mixture as in former cases. When the chloroform was separated, and a part of it evaporated in a capsule, the most beautiful and distinctive colours appeared after the employment of the proper tests.

This experiment was instituted for the purpose of ascertaining whether strychnia is liable to undergo any change in the presence of organic matter by the lapse of time, even where that matter has fermented and exhibited evidences of incipient decomposition. The result affords a strong inference that it could be detected in the contents of the stomach after a body had been deposited several days in the grave.

I carried this experiment a step further with a view of determining whether morphia could also be regained from an organic mixture in a state of commencing decomposition. Consequently, after separating the chloroform and caustic solutions from each other, I added acetic acid to the latter, drop by drop, until it was neutralised. Then a solution of tannic acid was added, and the precipitated tannate was collected and dissolved in acetic acid. The solution afforded a red colour with nitric acid, and a rich blue colour with the persulphate of iron, and was, moreover, very bitter to the taste, thus establishing conclusively the presence of morphia.

Having entirely satisfied my own mind by the fore

353

going experiments that no inherent difficulties exist in the detection of strychnia by the colour-tests when it is associated with morphia and involved in a great mass of animal and vegetable matters, I might with propriety dismiss the subject; but as so large a quantity as a grain of the poison might not be found in the stomach after death, in consequence of the use of emetic remedies, or the partial absorption of what had been swallowed, I concluded to try the process on a much smaller scale, and accordingly performed as follows:

Experiment 8.-Two ounces of minced meat (similar to that used in experiments 4, 5, 6, and 7), and two ounces of bread, were macerated eight hours in four fluid-ounces of water, holding in solutionth of a grain of strychnia and 3rd of a grain of the sulphate of morphia.

Half a fluid-ounce of acetic acid, with an equal measure of water, was added, and the mixture set aside for six hours. It was then strained with pressure and filtered. The remaining clear liquid was divided into two portions, a and b.

One portion (a) was placed in a capsule in a current of air at 70°, and thus evaporated to a syrupy consist ence. It was treated with the caustic solution and chloroform, as in the former cases; and, upon careful application of the tests to the film obtained by evaporating the chloroform, clear and undoubted evidences of the presence of the poison were afforded by a transient yet distinct play of colours.

The other portion (b) was treated directly with a measure of chloroform and two measures of the caustic solution. After mixing these carefully together, the chloroform was drawn off, placed in a capsule, and evaporated spontaneously. A very delicate filmy deposit, of a white colour and bitter taste, was observed in the capsule. A part of this gave, with sulphuric acid and ferricyanuret of potassium, a distinct but evanescent change of colours, indicating positively the presence of strychnia.

To determine more satisfactorily the precise nature of the deposit obtained from this experiment, I evaporated upon a slip of glass drop after drop of the chloroformic solution, until an appreciable deposit was procured, and to this a drop of dilute nitric acid was added. When dry it was placed under a microscope at a magnifying power of 100 diameters, and a crop of well-defined crystals of the nitrates of strychnia and brucia was apparent.

This experiment proves conclusively that strychnia in minute quantities can be regained from organic mixtures, notwithstanding the presence of three times its weight of sulphate of morphia.

In conclusion, I may be permitted to offer to those who shall be called upon to determine the presence or absence of strychnia in cases of suspected poisoning, a few practical suggestions, viz:

1. In testing for minute portions of the poison, success or failure depends entirely upon the care given to the details of the process.

2. In examining the contents of a stomach, the employment of heat is not required for the detection of strychnia, nor should any unnecessary fluid be added which might require subsequent evaporation. Equal measures of acetic acid and cold water, in sufficient amount to thoroughly acidulate the mass, are all that is