jodine from an iodurated iodide of iron, obtained by the action of iron filings and sulphuric acid on the water of the bath, and afterwards decomposing the product obtained by bichloride of mercury. In the description of these processes, there are several points which have appeared not very reasonable to your commission. Among others, that of mixing the iodine obtained with iron filings, to be afterwards purified by distillation. Independently of the inconvenience of the method pointed out by M. Righini, a great portion of the iodine must remain combined with the iron, in the state of a fixed iodide of iron. 6. M. Cottereau, jun., proposes to modify the decomposition of iodurated baths by acetate of lead, by acting on the iodide of lead thus formed, by means of heat and a solution of carbonate of potash, or by a solution of sulphate of potash. The iodide of potash, regenerated by this reaction, is afterwards obtained by evaporation, and purified by crystallisation. The author dwells upon the fact of sulphate of potash being a commercial article less expensive than the carbonate of the same base. 7. The communication of M. Giovanni Ruspini, has, for its object, the employment of acetate of lead and the decomposition of the iodide of lead by sulphuric acid and peroxide of manganese. 8. The process recommended by M. Bouyson is analogous to the proceeding; it differs from it only by the employment of subacetate of lead, instead of the neutral acetate. 9. M. Leudet has applied the combined action of bisulphate of copper and metallic copper on the iodurated iodide of the baths. He thus transforms the whole of the iodine into protoiodide of copper, which he afterwards decomposes by hot sulphuric acid and peroxide of manganese. 10. M. Cottereau, in a note in addition to his first memoir, recommends the subacetate of lead and the decomposition of the iodide of lead by carbonate of potash. 11. M. Clement has applied the processes of Messrs. Berzelius and Soubeiran for the extraction of the iodide of the mother waters of kelp potash; he precipitates the iodurated baths by a mixture of protosulphate of iron and bisulphate of copper, and decomposes the iodide of copper obtained by means of carbonate of soda-a low-priced salt. The result of this reaction is a soluble iodide of soda, which he employs in that state for the preparation of a fresh bath by the addition of a sufficient quantity of water. This process appears to us to be economical, since it dispenses with the necessity of evaporating the liquid containing the iodide, which can be em. | ployed several times in the preparation of an iodurated bath. 12. M. Minard employs acetate of lead to precipitate the iodine from the bath; but he afterwards treats the iodide of lead with caustic potash, and decomposes the product by sulphuric acid with the assistance of heat. The same author proposes to convert the iodide of lead into the iodide of potash, by dissolving the first in boiling water, and precipitating by a solution of carbonate of potash. To sum up all the different methods we have passed in review, as it were, are founded on the previously published processes of Messrs. Berzelius, Liebig, and Soubeiran, for extracting iodine from the mother waters of kelp potash; they, therefore, offer no originality of character. On this account the commission, by their reporter, do not think they should grant the silver medal; but considering the efforts made by the different authors to answer the question proposed by the Society, it proposes, by way of encouragement and honourable notice, to grant six bronze medals to those who have most nearly attained the proposed end. Namely, to M. Legrip, M. Cottereau, jun., M. Leudel, M. Clement, and Messrs. Labiche and Chantrel. Decastere.... ...... =353.17 Healthy human fæces, therefore. posses the property of exciting fermentation, when they have themselves passed into a state of fermentation or putrefaction; but they ac The next table represents the names and quire this state only after being expelled ratios of French weights : from the body, and when subsequently exposed to the air. The disappearance during fermentation of their peculiar foetor is itself a fact full of significance with respect to the view to be entertained of their true nature. The disengagement of gases which goes on in the intestinal canal of persons who are out of health, or affected with disease, shows the facility with which the fæcal matters, from causes operating within the body, may pass into decomposition analogous to putrefaction. It may perhaps not be unimportant to the decision of the question as to the nature of the fæces, if I direct the reader to the fact, that it is easy, by an imperfect oxidation of albumen, to produce the peculiar substance to which the fæces unquestionably owe their peculiar foetor. If we heat in a retort one part of white of egg and three of hydrate of potash, so as to melt the mixture, and continue the heat till the disengagement of ammonia has nearly ceased, and if we then supersaturate slightly the contents of the retort, after cooling, with dilute sulphuric acid, and distil, we obtain, along with a disengagement of carbonic acid and sulphuretted hydrogen, a liquid which is slightly acid (from the presence of acetic and butyric acids), and which has a most horrible fæcal smell. The substance to which the smell belongs is soluble in water and alcohol; it combines with alkalies, without, however, neutralising them; when exposed to the air, it is rapidly changed. By means of caseine, gelatine, and fibrine, when treated in the same way, we can procure all the different varieties of fæcal odour. The fæces of a sucking child, which, under the miscroscope, appeared to consist, for the most part, of epithelial cells, swelled by moisture, caused, during three days, no fermentation in the solution of sugar; on the fourth day, bubbles of gas appeared; on the fifth, a regular fermentation set in, and the sugar disappeared. By distillation, there was obtained a thoroughly well-flavoured spirit. As soon as the fermentation set in, the so-called fungi of fermentation appeared. A NEW METHOD FOR DETECTING The fæces of a healthy adult, in two other experiments, produced no fermentation, even after five days. Those of a second individual, suffering from weak digestion, produced in the saccharine solution, by the end of the first day, a feeble fermentation, in consequence of which the fæcal smell entirely disappeared. By distillation, there was obtained a very small quantity of alcohol, of a most offensive smell, as of putrid cheese. When the same person had taking, fasting, a certain quantity of salt and water, to promote the action of the bowels, and the consequent evacuation was richer in swollen epithelial cells, a perfect fermentation took place. N.S., VOL. IV. SPURIOUS MUSK-PODS.* BY J. MOORE NELIGAN, M.D. OWING to the high price and great demand for musk, both as a medicine and a perfume, it is very generally much adulterated. This fact is so well known to apothecaries and to druggists, that those who have even a moderate consumption of the drug prefer purchasing it in the unopen musk-bag, or, as it is technically called, musk-pod. This precaution, however, is often found not to be a sufficient protection against fraud, as spurious musk-pods are not uncommon in com *Dublin Journal of Medical Science. 3 U merce, so well prepared that even the most experienced eye is often unable to distinguish the true from the false. It is now very generally known that musk is the peculiar secretion of a small sac situated immediately in front of the preputial orifice of the male musk animal, the moschus moschiferus, and that it is principally imported into the British market from China. The Chinese, finding a greater demand for musk than they are able to supply with the genuine article, squeeze out some of the secretion, which is fluid in the recent state, and mix it with, it is believed, the dried blood of the animal; this compound, which presents the same physical characters as true musk, they put into small sacs made of pieces of the skin cut off from other parts of the animal's body, and prepared with the usual ingenuity of this people, so much so, indeed, as almost to defy detection with the naked eye. The method hitherto adopted for detecting this sophistication has been the peculiar position of the hairs, which are arranged in a circular manner around the orifice in the genuine musk-pod; and also the absence of any remains of the penis in the artificial pods. But those characters are not invariable, and I have seen some spurious muskpods which were so skilfully prepared as to be undistinguishable from the genuine article when compared with them. The plan which I propose depends on the microscopic characters of the hairs which grow on the preputial sac of the musk animal, and which, as far as I have been able to detect by direct experiment, differ very remarkably from those of the false sacs which are met with in commerce. This test I have recently had an opportunity of pointing out to my friend Professor Christison, of Edinburgh, and of illustrating it to him from specimens in his own museum. The difference appears to depend on the fact, that the hairs of this part of the animal are furnished in the interior with distinct, regular, coloured cells, while in hairs taken from other parts of the animal's body those cells appear to be obliterated, as is generally the case in this and the allied tribes of animals. The method I have now proposed is a very simple one, and of easy application, and cannot be considered too scientific in the present day, when every pharmaceutist must be supposed to be provided with a microscope at the least of the power above spoken of, without which he could not possibly detect the adulteration of arrow root and of the other feculas of commercc. CASE OF POISONING BY OIL OF VITRIOL AT WANDSWORTH. WHEN we inserted, in our last number, the reprint of a letter that appeared in the pages of the Lancet, we had not the most remote idea of giving reasonable offence to Mr. A. S. Taylor, or his friend. The statement was inserted because it was an apt illustration of the chance of error in giving chemical evidence without previous experiment. Mr. Taylor has forwarded us a pamphlet, in which the evidence given by the surgeon is reported as follows, together with the witness's explanation: "What strength of diluted sulphuric acid would serve to produce such injuries as you saw?-The dilute sulphuric acid of the Pharmacopoeia, which is one-fifteenth acid to fourteen-fifteenths water, or thereabouts, would produce injury to the mucous membrane of the mouth; but what I saw must have been produced by a much stronger fluid. An overdose of that aniseed might embarrass a child, but would produce no dangerous effects. 'By a Juryman: What would be the difference, if any, in the appearance of vitriol and water, and aniseed and water, when separately mixed; and would either two, when mixing, produce any effervescense, or other effect which would distinguish them one from the other?-Hot water, as in this case, being added to the aniseed, with a lump of sugar, some bubbles would escape from the surface whilst the sugar was dissolving; but in mixing sulphuric acid and water hot, the fluid would remain clear. There might be a trifling difference perceptible afterwards in the colour of the mixture. "By Mr. Locke: An ordinary person might not notice any difference in the two fluids, contained as they are in two bottles so similar, unless their attention was directed to it. I should discover it. "On further reflction, it occurred to me, that I had not included the sugar in speaking of the mixing sulphuric acid and water, in answer to the juryman's question; and bearing in mind that Mrs. Barker had invariably asserted, and had that day sworn, that she had put aniseed first, then sugar, and lastly water, I produced in court a mixture of one drachm of sulphuric acid, with a lump of sugar, and then a drachm of water added to them. The result gave a black fluid, at a very high temperature. Mr. Locke begged to know if I had mixed the three ingredients in the following order-the acid first, then the water, and, lastly, the sugar. I said, no. He asked me what would be the effect. I said, I thought something similar to the other whether the liquid swallowed by the child would, or would not, carbonise sugar; since, according to my experiments, which are only confirmatory of those of other chemists, sulphuric acid, which is so diluted as not to carbonise sugar, will certainly not charr blood, mucus, or mucous membrane. Nevertheless, as it will be seen by the mode in which the learned counsel dealt with Mr. Tatham's evidence, this, which I believe to be a chemical impossibility, was forced upon the jury as a truth-There was no change of colour, as they the jury had seen. Therefore, the mistake might have been made by Mrs. Barker !' mode. He then begged me to make such a mixture before the court, telling me to put double the quantity of water to that before used. This I did, and the effect was a deep yellow fluid, of intense heat, and which gradually became darker on cooling. The quantity of sugar left for this experiment was only a few grains. This Mr. Locke described as a mistake, and said it went to prove the possibility of Mrs. Barker's having used the vitriol in lieu of the aniseed. Now Mrs. Barker, in all her examinations, including her evidence that day in court (and her statement on this subject was confirmed by the prisoner herself, on the night of the accident), had stated most distinctly that she put the "Mr. Harrington goes so far as to assert, aniseed first in a cup, then a lump of su- in the paper referred to, that the innocence gar, and afterwards added hot water out of or guilt-indeed the hanging of the accused the teakettle; so that, had she used vitriol-depended on the simple fact, whether instead of aniseed, an ebullition would first have taken place, and then a black fluid product at a very high temperature would have appeared around the sugar, surely calculated to arrest her notice ere she administered it to the child as an aniseed mixture." On this and the evidence of the mother of the infant, Mr. Taylor observes, reflecting at the same time on the statement of the cor respondent of the Lancet "A very erroneous ex parte statement, in reference to this subject, has been lately published in a medical periodical, communicated by Mr. J. J. Harrington, attorney for the prisoner. Although it had been distinctly sworn on the trial by a witness (Mrs. Baker) who could no thave known the importance, in a chemical point of view, of her answers, that the sugar and liquid (whether aniseed or vitriol) had been mixed before water was added, t writer assumes that the water and anisced were most thoroughly intermixed before the addition of sugar; and contends, from his own experiments, that the medical opinion given by Mr. Tatham, which, as it will be seen, was based upon sworn evidence, and not on any assumption of bis own, was erroneous. It is only fair to suppose that Mr. Harrington could not have known that the results, arising from the mixture of vitriol, sugar, and water, depend materially on the order in which the substances are mixed for there is no apparent reason why he should have suppressed a fact so important, and so necessary to the formation of an opinion as to the truth or error of the chemical testimony. As it is, the reader is left to conjecture how, and in what way, the witness (Mrs. Barker) had mixed the ingredients alleged to be poisonous. The fact that the contents of the stomach were completely charred to a tarry liquid renders it almost unnecessary to discuss the question, | sugar would, or would not, be carbonised under the circumstances. If this view be correct, and if there be any faith in chemical experiments, repeatedly performed, he has unintentionally, but conclusively, proved that the accused was guilty; for when the ingredients are put together in the order and proportions sworn to, the mixture becomes invariably blackened, whether the acid, sugar, or water, be added first; always provided the acid and the water be not in the first instance well shaken and mixed. If, however, an individual be permitted to assume that the three substances were mixed in an order different to that repeatedly sworn to, and to draw an inference from this assumption contrary to the evidence adduced, it would be better to assume at once that no sugar was used. It appears to me that we are bound to take the experiment according to the evidence, when there cannot be the slightest suspicion of fabrication, or to reject it altogether. We have no right to twist facts of this kind to suit our own particular views. Mr. Harrington cites this as a case showing with what caution what he calls" speculative" chemical testimony ought to be received in Courts of Law; but the result of this investigation appears to me to show that a Court should exercise the greatest caution in not allowing itself to be imposed upon by chemical experiments entirely at variance with the facts proved. Let us suppose that it had been given in evidence that the liquid (aniseed or vitriol) had been well mixed with water before the sugar was added,-Would a medical witness have been permitted to express an opinion unfavourable to the prisoner from results obtained by an inverse mode of performing the experiment? Assuredly not. Yet, what would have been denounced as gross deception in medical evidence, was received without comment as legal evidence in favour of the accused." IV. REVIEWS AND NOTICES OF BOOKS, &c. ANIMAL CHEMISTRY, OR CHEMIS- | education and qualifications of those who TRY IN ITS APPLICATIONS TO PHYSIOLOGY AND PATHOLOGY. By Baron Liebig. Edited by W. Gregory, M.D., F.R.S.E., &c. Third Edition. Part I. London: Taylor and Walton. THIS is the first part of a new and greatly enlarged edition of Liebig's Animal Chemistry; and contains the "the Chemical Process of Respiration and Nutrition," and the first section of the "Metamorphoses of Animal Tissues." The latter is entirely new, and is "devoted to a consideration of the method which ought to be followed, and of the principles which ought to guide us in the investigation of that important subject." Want of space prevents us this month from entering more fully into the important subjects treated on in this valuable work. BECKMANN'S HISTORY OF INVENTIONS, DISCOVERIES AND ORIGINS. Translated by W. Johnson. Fourth edition, carefully revised and corrected by W. Francis, Ph.D., F.L.S.; and J. W. Griffith, M.D., F.L.S. Vol. II. London: H. G. Bohn. WE have here the completion of this very useful work, which is rendered more valuable by the notes and corrections of its able and industrious editors. Mr. Bohn is entitled to great praise for the admirable manner in which this work is put before the public: and we can only account for the marvellous cheapness at which it is published, by referring it to the mighty powers of steam; by which have devoted themselves to it-who, by their character and conduct, have raised it from the questionable position it formerly occupied in the eyes of the public; and by their writings and discoveries have not only caused it to be looked upon in the present day as a branch of a liberal profession, but one of vast scientific importance in the human organisation. Mr. Robinson has divided his treatise into two parts; the first commencing with the history of the art-after which he proceeds to explain, by well-executed engravings, the original formation of the teeth; their position at first; infantile diseases from teething; the foundation and advancement of the second caries, and method of stopping, &c. set; prevention of irregularities; causes of In the treatment of irregularity by mechanical means, the author has shown great mechanical ingenuity in the invention of a series of contrivances for correcting those deformities, as also in the invention of instruments used in extraction, &c. The second part is wholly practical; containing an elaborate and well-arranged treatise on mechanical dentistry; in which every manipulation connected with the manufacture of artificial teeth, gold plates and springs, swivels, suction-pieces in bone, alloys of gold, assaying, as applied to the dental art; all of which are minutely and handsomely illustrated. The work concludes with two important and interesting chapters on dentonomy and dental education. "literature is cheapened, and, by being CHEMISTRY AND PHYSICS IN REcheapened, diffused." THE SURGICAL, MECHANICAL AND MEDICAL TREATMENT OF THE TEETH; INCLUDING DENTAL MECHANICS. With 139 engravings. By James Robinson, Surgeon-Dentist to the Metropolitan Hospital. Webster, 60, Piccadilly. DENTAL Surgery, of late years only, has attained the rank and assumed the station and importance to which it is so justly entitled; and this is mainly owing to the superior LATION TO PHYSIOLOGY AND PATHOLOGY. By Baron Justus Liebig, M.D., F.R.S. London: Baillière. THE work now before us, although written in a singular style-for, in fact, it chiefly and deductions from established data-is consists of a series of axioms, suggestions, admirably adapted to excite the mind of the reader, and produce a stream of deep and useful thought it is a text-book on which many a useful essay might be written; of this our readers can judge for themselves, by the following extract from the commencement of the work: |