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reservoir falls it immediately accelerates in speed. Duplicate lines of in. iron gas-piping extend beneath the train, with ingenious indian rubber connections between the carriages. The breaks can be worked by sending the air through either line of pipes, so that if one fails the other remains serviceable, and further with two lines of pipes the carriages may be turned end for end, if necessary. The pipes not being in the centre line of the carriage, this could not be effected unless two symmetrical lines of piping were provided. The breaks are actuated by the air pressing on a piston in an air cylinder placed under each carriage. Hence the breaks can be instantly put in action by turning a cock and admitting air from the airreservoir to the piping. The pressure of air in the reservoir is 60 to 70 lbs. per square inch, but it is usually regulated not to exceed 10 to 30 lbs. in the air-cylinders. The details of this break, which are most ingenious and most carefully worked out, cannot be understood without drawings, and for these we must refer the reader to "Engineering" for May 24, where the invention is very fully described.

MEDICAL SCIENCE.

The Physiological Action of Tobacco has been very carefully studied by Herren Vogl and Eulenberg. They investigated the physiological action of (1) those bases volatile below 160° and (2) of those volatile between 160° and 250°. Both portions act like nicotine, producing contraction of the pupil, difficult respiration, general convulsions and death. They act more quickly by the stomach than when sub-cutaneously injected, but even then are not as prompt as nicotine. On post-mortem examination, the lungs and air-passages were found to be highly congested. They think that the disagreeable symptoms produced in the incipient smoker, and the chronic affections which excessive smoking produces, as well as the poisonous effects of tobacco-juice when swallowed, are due to the pyridine and picoline bases, and not to nicotine. They explain the fact that stronger tobacco can be smoked in cigars than in a pipe, by finding that more of the volatile bases are present in the smoke of a pipe; more especially of the very volatile and stupefying pyridine; while in a cigar, little pyridine and much collidine are formed. The authors compared this action with that of the bases obtained from other plants used for smoking; with those from dandelion, willow-wood and stramonium, and with pure picoline from Boghead coal. The action was entirely similar, but, with the exception of the willow wood bases, they produced no contraction of the pupil. Picoline in vapour is extremely poisonous, producing great irritation of the air-passages, convulsions and death. From these results the authors believe that the different effects of smoking opium are due simply to a difference in the proportion of the bases produced by its combustion.-Arch. Pharm. II. cxlvii. 130.

The Supposed Syphilis Corpuscles.-The "Monthly Microscopical Journal" of April, quoting from the "Allg. Wiener Med. Zeit.," says that the latter contains a serio-comic article on this discovery of Lostorfer, which, for a few moments, shook such men as Stricker, Hebra, and Skoda off their

balance. Dr. Wedl, the author of the article, says: "These corpuscles will, at the next meeting of the Medical Society, be solemnly buried in Dr. Stricker's museum. The sympathy of the profession is requested under these painful circumstances, and the Society will doubtless institute special masses for the repose of the departed. It is very lucky that the members did not, in their hurry, have medals struck for the discovery; and there is time left to send counter-orders to Paris and London, to stop enthusiastic researches which might bring some blame on the Vienna Medical Society. The latter may derive from this mishap the lesson to beware of allowing itself to be made a trumpet to ephemeral discoveries." The "Lancet," however, finds it difficult to believe-and the "Microscopical Journal " quite coincides with it-that observers like Stricker and Hebra would have been carried away by imperfect experiments. It is clearly stated that different. kinds of blood were placed under Dr. Lostorfer's microscope (he not knowing whence the blood came), and he constantly recognised his peculiar corpuscles in blood coming from patients affected with syphilis.

Colourless Bile.-In the "Comptes Rendus," March 18, M. E. Ritter quotes the results of a series of analyses made by him on colourless bile, taken from the gall-bladders of men and animals submitted to autopsy. As an instance of the composition of such bile (as yet hardly ever analysed, since the colourless fluid has been taken to be mucus) we mention here the following, in 1,000 parts:-Water, 923·5; salts, 12-4; fat and cholesterine, 6·8; organic matter, 2·1; salts of the bile acids, 55.2. It appears that colourless bile and fatty degeneration of the liver are somehow connected together. Ancient Egyptian Perfume.-Dr. Personne states in the "Journal de Pharmacie," March, that he accidentally obtained a small piece of a chocolatebrown substance, which originally was apparently a paste, but is now hard. On further examination it was found to consist of a lime-soap, mixed with myrrh, olibanum, benzoin, and probably some essential oil. Dr. Personne states that at the present day there is sold in Egypt as a perfume a substance of similar composition, and locally known as Bouh Kourre-bare, which means perfume from the Arabian frontier.

A Mechanical Means of Lowering the Temperature, which is peculiar, is described in a late number of Pfluger's "Archiv," by Herr Manassein. He states that, if rabbits, seated at ease in a box, were swung in a transverse direction to their length, and with a rapidity of twenty-eight to thirty double swings, at a pendent length of 117 ccm., that the temperature taken in the rectum after the swinging was, by 0.3° to 1.2° C., in the mean by 0.66°, lower than before. The depression of temperature continued from a half to two hours, and was most decided after fifteen minutes of swinging; a longer swinging did not increase the effect. The maximum of the depression of temperature occurred, at first, some time (about thirty minutes) after the cessation of the swinging. The last-named circumstance, as well as that the wrapping of the animals in cotton-batting in no wise hindered the effects, and, on the other hand, that a more rapid swinging appeared less effective, prove that the current of air which is produced by the swinging is not the cause. Swinging in the longitudinal diameter made the animal more afraid and more restless; it had, however, the same influence upon the temperature. The effects of the swinging on rabbits were greater

where the eyes were blinded, and less, on the other hand, in animals in which the respiration was moderately disturbed by the tightening of a cord around the neck, and also in animals only slightly narcotized by morphine. In injections of an ichorous fluid, the feverish increase of temperature produced was lessened by the swinging, and indeed, by repeated swinging, brought to a stop.

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Influence of Dr. Wright's Morphic Compounds on the Animal Body.— Some experiments on this subject were carried out by Dr. Reginald Stocker, Pathologist to St. Mary's Hospital, and are of interest. He says that doses of 1 decigramme of the compound Ces H81 IN, O10, 4HI from codeia, and of the similar compound from morphia, were given to an adult terrier by the mouth without producing any perceptible effect whatever; when the dose was increased to 3 decigrammes, in each case repeated defæcation in the course of a few hours was produced, the stools being more loose than ordinarily and frequently of a dark greenish colour; no other symptom was noticeable, and no appreciable difference in the action of the two compounds was perceptible. Doses of 5 decigrammes of the compound C H82 L2 NO10, 4HI from each of these sources were given to the same dog by the mouth, with the result of producing similar repeated defæcation in the course of two or three hours; the sole difference discernible between these and the former experiments being that the effect was produced somewhat sooner and was of longer continuance in the latter cases, a result probably produced solely by the larger dose. No material differences were observed between the codeia and morphia derivative. The same dog was employed throughout, two or three days being allowed to intervene between each experiment, so that the animal had recovered from the effects of a former dose before the administration of another.-Proceedings of the Royal Society, for April, 1872.

Gastric Juice and Pepsin applied to Wounds.-The "New York Medical Journal" states that there have been performed recently a number of experiments with the above fluids, applied as follows: the gastric juiee of dogs was pencilled, at short intervals daily, fifteen to twenty times upɔn the wounded surface, or small pledgets of cotton were applied, and upon them a second larger layer of wadding dipped in a very dilute solution of muriatic acid. Several experiments were made, especially upon chancres, upon soft chancres in particular. After five to eleven days, commencing cicatrization followed as a rule. The remedy is chiefly indicated in soft chancre, in diphtheria, phagedæna, and nosocomial gangrene.

A Curious Memento of Jenner.-A very interesting memento of the discoverer of vaccination has recently been presented to the Royal College of Physicians by Sir John William Fisher. It consists of a cow's horn, beautifully polished, presented to Sir J. W. Fisher, in the year 1813, by Dr. Jenner, and polished by himself. The gift was made in grateful acknowledgement of services rendered to Jenner's sick children by Mr. Fisher, then a medical assistant in Soho. The horn is now mounted in silver, and bears an appropriate inscription, stating the circumstances under which it was presented to the college. Dr. Burrows, the President, in asking the acceptance of the horn, stated that it was probable-though there was nɔ record of the fact-that the horn had been taken from one of Dr. Jenner's favourite cows on which he made his experiments on vaccination.

Atheroma in the Arteries.-Dr. Moxon has been making some recent researches on this subject, which are of importance. He shows the connexion between inflammation of the arterial tunics, atheroma, and aneurism, and he dwells upon, and accounts for, the relatively greater frequency of the latter affection among soldiers. Dr. Moxon holds (1) that what is called atheroma of arteries is sub-inflammation of various degrees, of which the lower degrees end in fatty degeneration of the coats, along with the inflammatory products; and (2) that the determining cause of this change is mechanical strain, a general altered nutrition-such as obtains in gout, syphilis, &c.-being regarded in the light of a predisposing cause.-Vide Lancet, June 8.

Chemical Composition of Pus.-The "British Medical Journal" states, in a recent number (May 28, 1872), that Hoppe-Seyler has obtained results which are interesting in reference to the question of the origin of the puscorpuscles and their identity with the colourless and lymph corpuscles. He introduced fresh crystalline lenses of the ox into the abdominal cavity of dogs, and analysed them after a period varying from one to fourteen days. As was expected, the lenses became infiltrated with lymph-corpuscles. Glycogen was found in greatest abundance at the eighth day, at which period they contained the greatest number of contractile corpuscles. The glycogen is due to these corpuscles. If the lenses were not plunged immediately into boiling water, but allowed to stand for some time, no glycogen was found, but in its place sugar. In the pus of congestion-abscesses, no glycogen occurred. The occurrence of glycogen, therefore, may be taken as a means of distinguishing lymph from pus-corpuscles. When glycogen is found in abscesses, it will be found to coexist with the presence of numerous contractile corpuscles. Lymph-corpuscles, therefore, by their transformation into rigid pus-corpuscles, become deprived of their glycogen. Animal Starch.-The "British Medical Journal" in one of its May numbers, gives an account of M. Dareste's researches on this point. It says he has observed granules which present the optical characters of starch in the hen's egg, both when newly laid and during the process of incubation. The granules in the new-laid egg give a blue with iodine; while those observed during incubation sometimes give a blue, but often give a red. The granules appear and disappear several times. The formation of the area pellucida is partly due to the disappearance of the third series of granules. The fourth series form the glycogen in the liver. He attributes the disappearance of starch to its conversion into grape-sugar, and its reappearance to the change of grape-sugar back to starch.

Action of Alcohol on the Body.-This subject is yet far from being exhausted. Dr. Subbotin gives in the "Zeitschrift für Biologie" (Band vii., Heft 4), also "Lancet," June 8, 1872, the details of a considerable series of experiments he has recently performed on rabbits. The mode of detection of the alcohol he employed was its acetification by chromic acid, or rather by bichromate of potash and sulphuric acid, the quantity being determined by the subsequent estimation of the distilled acetic acid by means of soda solution. The respiration experiments were conducted in an apparatus lent to him by Voit, and constructed on the plan of the large apparatus of Pettenkofer and Voit. Alcohol of the strength of 29 per

cent. was injected into the stomach through the exposed œsophagus, and this tube at once ligatured. The results at which he arrived were: That, during the first five hours after the introduction of alcohol into the stomach, a considerable amount escapes by the skin, lungs, and kidneys; that at least twice as much escapes by the lungs and skin as by the kidneys; that the amounts he obtained, showing that from 6-79 to 74 per cent. were thus eliminated, were, from various considerations, certainly below the quantities really discharged from the system. These conclusions he arrived at in 1870. Quite recently, however, he instituted another series of experiments, the object of which was mainly to determine for how long a time after ingestion alcohol continued to be excreted by the skin and lungs. In one of these experiments he found that 12.6 per cent. of the alcohol was eliminated in eleven hours and a half through all these channels; in another instance 16 per cent. was eliminated in twenty-four hours, either in the unaltered condition or only changed into aldehyde. Subbotin maintains that alcohol cannot be regarded as in any sense a food, since, under its influence, the metamorphosis of tissue diminishes, the temperature falls, the amount of carbonic acid excreted lessens, and a smaller quantity of urea is discharged. Its action, he thinks, is direct upon the nervous system.

METALLURGY, MINERALOGY, AND MINING.

An Improvement in Blowpipe Operations.-MM. Armin, Junge, and Mitzopulos, of Freiburg, have greatly improved the blowpipe by an apparatus of which the following is a description :-A common wide-mouthed bottle is carefully fitted with a caoutchouc cork bored with two holes, into each of which passes a piece of glass tube bent at a right angle. On to one of these tubes is slipped the caoutchouc tube coming from an ordinary caoutchouc bellows, whilst the other is put in communication with the blowpipe nozzle by means of four pieces of caoutchouc tubing joined by three pieces of glass tube, drawn to a fine point at each end. This forms the main peculiarity of the arrangement. When air is forced into the bottle by the blower, in jerks, it finds a difficulty in escaping as fast as it comes in, on account of the six fine openings in the glass tubes that it has to pass through on its way from the bottle to the nozzle, and it thus acquires a certain pressure in the bottle, and flows out towards the nozzle as a regular blast. The bottle may be about 6 inches high by 31 inches wide, with a neck 1 inches in diameter; but of course the dimensions are of no great importance. On the whole a somewhat large bottle is better than a small one. The pieces of glass tubing used are 2 inches long by of an inch in diameter. The apparatus will be stronger if instead of a glass bottle a tin cylinder is used, about 4 inches high by 2 inches in diameter, with two tin tubes opening into its top. Small metal cylinders, with a fine hole at each end, may be used instead of the little glass tubes. A blowing apparatus constructed in this manner will deliver a perfectly regular blast, and will be of practical interest to those who are thinking of working in places where it is impossible to repair the ordinary instruments.-See Chemical News, June 7th.

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