Dr. Caro Parascandolo, in experiments on dogs and rabbits, has studied the lesions of the nervous system that occur after burns of various degrees of severity. He has found retraction of the gray matter of the cord with deformed posterior cornua and perinuclear and peripheric chromatolysis in the cells; sometimes what he terms homogeneization of the protoplasm; sometimes granular degeneration of chromatin with presence of chromatic rods in the nucleus; and sometimes total achromatylosis with destruction of the tissue network. The protoplasmic processes presented varicose atrophy or lost their connection with the cell body and were augmented; and degeneration of the cord, affecting the posterior cornua, was the rule. The author concludes that as the result of burns ptomaines make their appearance in the blood and muscles and other organs of animals suffering from them, and cause death by bringing about anatomical changes in the nervous centers. The alterations observable are similar to those met with in different types of infection. It is particularly worthy of notice that these ptomaines are capable by inoculation of producing in the nerve centers the same lesions as are observed in the case of burns.

The salient points brought out in an investigation by Prof. Louis Kahlenberg, of the University of Wisconsin, of the action of solutions on the sense of taste may be summarized as follow: In order that a substance may affect the sense of taste, it must be soluble in water, must be readily diffusible, and must be capable of reacting chemically with the protoplasm of the terminals of the nerves of taste. The modern theories of solutions lead to the conclusion that the taste of a solution that conducts electricity ought in general to be that of the ions and the undissociated molecules that the solution contains: sour taste is caused by hydrogen ions, while hydroxyl ions produce an alkaline taste, which in strong solutions is exceedingly disagreeable; chlorine ions have a salty taste, bromine ions one that is similar, but slightly different in quality from that of chlorine ions, while iodine ions have a salty taste that is different in quality and less intense than that of either chlorine or bromine ions. The taste of NO, ions is slight, probably a trifle salty. Only in strong solutions do they produce a sharp burning sensation on the tip of the tongue. The ions SO, and CH3COO have but very little taste, the effect of the latter seeming to be a trifle sweet. The taste of sodium ions is slight, and is only imperfectly described as being a smooth effect on the tongue, somewhat similar to that produced by a very dilute solution of hydroxyl ions. Potassium ions have a more pronounced taste, peculiar, bitter, and rather disagreeable. Lithium ions have no pronounced taste, having a similar effect, but less in degree, with that of the sodium ions. Magnesium ions are bitter, and calcium ions too, but with a taste different in quality from that of magnesium ions. Silver ions have a metallic taste and cause a peculiar puckering sensation in the membranes of the mouth cavity. The taste and effect of mercury ions are somewhat similar to those of silver. The intensity of the salty taste of the halogen ions decreases as the atomic weight increases. A relation in the sense of the periodic law also appears to exist between the taste and the atomic weights of the cathions. Instances are found that point to the conclusion that the greater the mobility of the ions as measured by their speed under the influence of the electric current, the more intense is the taste; but many exceptions point to the operation also of other factors. The intensity of the taste of solutions of substances containing amido-acid, alcoholic hydroxyl, and aldehyde groups was investigated, with results corresponding in general to what might

be expected from the relative readiness with which these substances permeate plant and animal membranes. The alkaloids have in general a pronounced bitter taste, as they permeate protoplasm rapidly and exert a strong physiological action on the nerves; while colloid solutions are tasteless because the substances they contain diffuse very slowly and are chemically inert.

In the examination of the color sensations of nearly 109 persons, Mr. G. J. Burch observed that by exposing the eye to bright sunlight in the focus of a burning glass behind a red screen a condition of temporary red blindness is induced, during which scarlet geraniums appear black and roses blue. Green blindness and violet blindness may be produced by similar means. The author has systematically investigated the appearance of the spectrum during the color blindness induced by exposure to intense light from various parts of the spectrum, and finds that the red from A to B. the green near E, the blue halfway between F and G, and the violet at and beyond H produce well-defined and characteristic results, indicating that each of these colors corresponds to a definite color sensation. In each case all direct sensation of the color used for fatiguing the eye is lost, but the observer is conscious of a positive after-effect of the same color, by which the hue of all other colors is modified. The temporary abolition of one color sensation is without effect on the intensity of the remaining color sensations. Any two, or any three, of the four color sensations—red, green, blue, and violet-can be simultaneously or successively exhausted. The observed facts are, in the author's opinion, more in accordance with the Young-Helmholtz theory than with that of Hering, but they imply the existence of a fourth color sensation, namely, blue.

A number of cases of what may be called color hearing, or the association of a sense of color with certain sounds, are described by Dr. W. S. Calman, who finds that they may fall into two groups. In the first group a crude color sensation, often very beautiful, is associated with certain sounds, as those of the vowels severally, and of musical notes and instruments. The appearance is usually that of a transparent film like a rainbow, in front of the observer. In the second group color sensations occur whenever letters or written words (symbols of sound) are spoken or thought of, so that when a word is uttered the subject visualizes the letters, with each of which a distinctive tint appears. The author is led from his studies of the subject to regard the phenomenon as one of "associated sensations analogous to the sensation of shivering which we experience in one part or other of the body at the sight or thought of an action, or when having to endure certain disagreeable or squeaking sounds. The tints excited are very definite and characteristic, each for its own sound, and do not vary as time goes on, while the colors are hardly ever the same in two persons.

Miscellaneous.-The results of more than one hundred cases are cited by MM. S. Arloing and Paul Courmont as showing that the aggregation of the tubercle bacilli when the blood serum is introduced into a culture may furnish, very rapidly, an important element of information in the early diag nosis of true tuberculosis. In two cases, however, the test failed, though tuberculosis was undoubted and in an advanced stage. The fact that positive results were almost always obtained when. the tuberculosis lesions were in an early stage is taken as showing that the serum reaction is the more valuable. Feeble aggregation was induced in some cases where tuberculosis was not found by the ordinary clinical methods, and the inference is drawn that latent tuberculosis may be consistent

with the appearance of perfect health. One of the latter cases afterward developed into tubercular laryngitis.

A form of the tubercle bacillus capable of existing in cold-blooded animals, such as the frog, has been described by MM. Bataillen and Terre. A third form of this bacillus, originally human, has now been obtained after a passage of three days in the frog. On solid media this form grows rapidly at temperatures between 12° and 48° C., and is distinguished from the form previously described by three points, appearance of cultures, power of easily developing at high temperatures, and possession of the property of rendering beef broth turbid. The colonies on the potato are brownish and the bacilli are not stained by the methods of Gram or Ehrlich. Experiments on animals have led to the conclusion that many cases of pseudo-tuberculosis are in reality true tuberculosis, having as a cause one of the forms of Koch's bacillus.

The relations of toxins and antitoxins, particularly in the cases of snake poisoning and diphtheria, have been investigated by Dr. C. J. Martin and Dr. T. Cherry with reference to the nature of the substances themselves and the nature of the antagonism between them. The first of these two problems has not been satisfactorily answered, but the authors have found that the materials in question have high molecular weights, and should be classed with proteids or proteidlike substances. Applying a method of separating substances of large from those of smaller molecular size in a solution containing both, it appeared that the antitoxin of diphtheria did not pass through the filter. Its molecular size was therefore presumed to be of the same order as that of a globulin. When antitoxic serum was filtered in this manner, all the proteids, and together with them all the antitoxic virtue, were absent from the filtrate. Toxin, on the other hand, the molecular size of which is of the albumose order, was not held back by the filter. Corresponding results were obtained with the toxin and antitoxin of snake poison. Concerning the nature of the antagonism between the two substances difference of opinions has prevailed, some authors believing it to be chemical, like that between an alkali and an acid, and others regarding the action as indirect, operating in some way through the cells of the organism. Experiments with cobra poison in which the antitoxin was destroyed by heating the solutions to 68° C. for ten minutes, while the venom was not attenuated, have been held to show that the toxin and antitoxin do not act in vitro, but only in corpore, or that the action can not be explained as a simple chemical operation. Such experiments are shown by the authors not to be conclusive, because in them no account is taken of time as a factor in aiding chemical action; and they present experiments of their own, illustrated by a graphic curve, showing that when the antitoxin is allowed to act upon the toxin for more than ten minutes before the solution is applied they completely neutralize one another in vitro. This result was obtained with both snake venom and diphtheria toxin and the antitoxin.

The chief points noted in a paper by W. B. Hardy regarding continued observations upon the action of the hyaline cells of frog's lymph upon bacilli, are that actual measurements show that contact with an oxyphil cell of frog's lymph retards or stops the growth of a chain of Bacillus filamentosus; that the action of the cells upon this organism is generally determined by temperature. Below 19° C. the cells usually completely arrest growth; between 20° and 25° C. the growth is only retarded. The cells exert the action by coating the chain with a slime which is derived from the oxyphil granules. Con

tact with a hyaline cell does not necessarily have any effect upon the rate of growth of Bacillus filamentosus. If the bacillus is inclosed within vacuoles developed in the cell substances, then retardation of growth occurs.

M. S. Arloing has found that the development of the immunizing effects of anti-diphtheric serum is influenced by the place and mode of introduction. When administered separately, its complete antitoxic action is greatest when it is introduced into the blood, and least when introduced into the conjunctive tissue.

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In a research by J. T. Cash and W. R. Dunstan on the pharmacology of certain alkaloids in relation to their chemical composition, the pure alkaloids aconitine, benzaconine, aconine, and an aconitine derivative, diacetylaconitine, were examined with reference to their action upon warm- and cold-blooded animals, a similar series of experiments being made with each alkaloid for purposes of contrast. It was found that if the dose of aconitine, which is invariably lethal per kilogramme body weight, be represented by the unit, that, in very general terms, diacetylaconitine would have of the toxicity of aconitine, benzaconine, and aconine. The variation in toxicity among these alkaloids is therefore enormous. The details of the chief results obtained and of the points of difference in the action of the several alkaloids are given in the paper of the authors. All the alkaloids examined reduce body temperature, though in varying degree. It is further pointed out that while the toxicity of aconitine mainly depends on the presence of the acetyl group, the introduction of two additional acetyl groups into the aconitine molecule does not materially alter the pharmacological action, but merely reduces the toxicity of the parent alkaloid. The removal of the acetyl group abolishes the stimulant action upon the respiratory center and pulmonary vagus. It also favors reduced activity in motor rather than in sensory nerve endings. The benzoyl grouppresent in benzaconine, absent in aconine-causes a peculiar and distinct modification in the heart's action, associated with a disturbance of sequence never witnessed after aconine. The curarelike effect of aconine and the intermittent failure of the stimulated benzaconine muscle are also traceable to the modification in chemical constitution arising from the absence or presence of the benzoyl group. Attention is drawn to the practical bearing of the fact that benzaconine and aconine, pharmacological antagonists of aconitine, occur with it in the root of Aconitum napellus, from which the medicinal preparations of the drug are made. In experiments to determine the action of anæsthetics on vegetable and animal protoplasm, J. B. Farmer and A. D. Waller studied the effects of carbon dioxide, ether, and chloroform with leaf of elodea and other plants and nerve of frog. The action of carbon dioxide was to produce an initial slight acceleration, followed speedily by a complete cessation of movement. On disconnecting the carbon-dioxide apparatus and aspirating air through the chamber, the protoplasm, after the lapse of two or three minutes, began to show signs of recovery. Fitful movements of the granules first occurred, and then they soon resumed their processional motion around the cell, at first very slowly. The movements rapidly became accelerated and considerably exceeded the normal rate. The acceleration did not last long, and was followed by a slowing down to the ordinary speed. The results of experiments with chloroform and ether are also given in the authors' paper.

Conclusions are drawn by E. Overton from comparisons of experiments in growing plants in sugars with observations made on autumnal leaves in the

Alps, that the red coloring matters of green plants are probably of the nature of glucosides, and are in most cases unions of tannin compounds with sugar. The chief factors in their production are sunshine, which, on the one hand, augments assimilation and the production of sugar, and, on the other hand, accelerates the chemical process leading to the formation of the pigment, and the low temperature, which prevents the conversion of the sugar into starch. In other words, the red autumnal tints are in great measure the direct results of the autumnal climatic conditions. It is possible in many plants to produce red autumnal tints at any time of the year by feeding with glucose. Generally speaking, this artificial production of red cell sap is possible only when the natural reddening of the leaf has its seat in the mesophyll cells. In cases where the coloration is in the epidermis experiments with glucose are unsuccessful.

As the result of the examination of numerous tumors, M. F. J. Bosc has found that the abnormal formations foreign to the tissues can be grouped under five morphological types-microbial forms, granulations, cellular forms of very variable origin, encysted forms, and sarcotic forms. All these forms exist in epithelia, carcinoma, and sarcoma, but sarcoma contains especially the microbial forms and the granulations.

Prof. Küttner, of Tübingen, found from experiments with Röntgen rays, at the Constantinople Hospital, that splinters of bullets and of bone which had penetrated into the soft parts of the body could not be distinguished from one another. It also appeared that the opinion that deep-lying pus could be located was erroneous. Injuries to the central nervous system, the spinal cord, and the peripheral nerves were solely ascertainable by the aid of the Röntgen rays; it was impossible to do this before. It could, further, be seen whether a bone was totally or only partially severed. It was recommended that photographs be taken for shot wounds in the extremities. The author concluded that the Röntgen rays are of great importance for medical aid in war, but only for fixed hospitals, such as reserve hospitals and those installed in fort reserves, while for moving field hospitals their application is very limited.

For a long series of observations upon the surface and the deep temperature of healthy men M. S. Pembrey and B. A. Nicol applied their tests to the urine and the rectum. The average of 343 observations upon the temperature of the rectum was 98.24 F., and that of 377 determinations of the temperature of the urine was 98.64° F. for a day of twenty-four hours. The average for the time of activity (7 A. M. to 11 P. M.) was 98.58° F. for the rectum, and 99.12° F. for the urine; while for the period of rest it was, respectively, 97.42° F. and 97.67° F. The maxima of the averages were 99.25° F. and 99.58° F.; the minima, 97.03° F. and 97.25° F. The times of the maxima were about 6 P. M. and between 4 and 5 P. M.; the times of the minima were about 2 A. M. and between 4 and 5 A. M. The maxima of all the observations, except those taken immediately after considerable exercise, were 100.6° F. and 100.1° F.; the minima, 96.8° F. and 96.9° F. Muscular exercise produced a marked rise, even as high as 101° F., in the temperature of the rectum and arine. This might be accompanied by only a slight rise or fall in the temperature of the mouth. The temperature of the mouth was found not to be an exact measure of the deep temperature of the body. It is unreliable after exercise or in cold weather, owing to the cooling of the mouth. In some cases the buccal temperature may be from 3° to 4° F. below the temperature of the rectum or urine. Mental work has apparently little influence upon the

temperature; it is generally accompanied by a fall in temperature, owing to the concomitant decrease in muscular activity. The effect of rest and sleep is to produce a steady fall in the temperature, and is the most important factor in producing the fall in the curve of daily temperature. The effect of food is to raise slightly (from 0.3° to 0.7° F.) the temperature of the rectum and urine, and, in the case of the evening meal, somewhat to delay the fall of temperature at that time. The mouth shows a relatively greater rise, owing to the increase in the vascularity and muscular and glandular activity of the tissues bounding the mouth. After a hot meal the temperature of the mouth is often above that of the rectum. The temperature of the rectum shows an average excess of 0.48 F. over that of the urine, and of 1.17° F. over that of the mouth, The average temperature of the urine is 0.82° above that of the mouth. The relative values, however, vary under different conditions. The surface temperature of the skin in the exposed parts of the body is liable to considerable variations, but that of the parts habitually covered by clothes is fairly constant. A simple flat-bulb mercurial thermometer readily gives results which compare favorably with those given by thermo-electric methods of determining the temperature of the skin.

The formation of enamel has been studied by Charles S. Tomes in the teeth of the Elasmobranch fishes, and he concludes that just as the teeth in that order present the simplest known form of tooth development, so they also present the first introduction of enamel as a separate tissue. In the first introduction it was a joint product, made under circumstances which almost precluded the formation of an outer layer upon the teeth; but in the further specialization of teeth in reptiles and mammals the tooth germs sink more deeply into the submucous tissue, and are protected for a much longer time. The enamel organs become more specialized, and finally take upon themselves the entire work of enamel building, manufacturing both the organic matrix and furnishing it with lime salts, as unquestionably happens in mammals. If these conclusions be correct, it would be quite justifiable to call the formation in these fishes enamel, even though the dentine pupila has had a share in its production.

The hepatic organ is found by M. A. Dastre, whenever it is present, to be always distinguished from the other tissues by the increased amount of iron it contains. Thus in the crustacea the liver is rich in iron, containing four times as much as muscle, while the blood and ovary contain practically none. In cephalopod mollusks the hepato-pancreas contains, weight for weight, twenty-five times as much iron as any of the tissues; in Lamellibranchs the ratio is about 5 to 1, and in Gasteropods the same. The presence of this iron is independent of the metal in the blood. Thus, when copper is present in the blood as hæmacyanin, iron only is present in the hepatic tissue.

It has been shown by M. Raphael Dubois that the active agent in the production of light by animals and plants is a substance possessing the characteristics of the zymoses, which has been named, from that fact, luciferose. The light is not the result of combustion, or even of direct oxidation. The fixation of oxygen was shown by subsequent researches to be necessary, but it is effected indirectly, or through the intervention of luciferose, which behaves in this relation like an oxidizing ferment. The luminous organs of glowworms and of the eggs contained in the ovaries of the female give a blue color with tincture of guaiacum. The blood of the glowworm and of some other insects give the same reaction; but the au