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a palliative, if not a specific, in a variety of skin diseases. The evidence adduced from the practice of several surgeons proves that it is a very valuable application in scalled head, in combination with hyposulphite of soda; in itch, combined with sulphur; in inveterate psoriasis ; in pityriasis, lepra, lichen, eczema, impetigo, prurigo; in certain forms of lupus, and of strumous and syphilitic eruptions. As a solvent or excipient, or vehicle for pharmaceutical preparations, glycerine is now much employed; and Messrs. Price and Co., of London, have prepared a series of medicinal compounds, in which glycerine is the solvent basis. It is much to be regretted that the price of. glycerine is still so high as to preclude its general use among the lower classes.

HALF-YEARLY REPORT ON PHYSIOLOGY.

BY HERMANN WEBER, M.D.
Licentiate of the Royal College of Physicians, Physician to the German Hospital.

I. ON FOOD AND DIGESTION. 1. VERNOIS and BECQUEREL: Analysis of the Milk of the principal types of

the Cow, the Goat, the Sheep, and the Buffalo. (L'Union Médicale, t. xi.,

No. 26, 1857.) 2. BERTHÉ: On the Assimilation of different Oleaginous Substances. (L'Union

Médicale, t. x. No. 62, 1856.) 3. COKVISART: On a Function of the Pancreas which is little knoron: Digestion

of Azotized Substances. (L'Union Médicale, t. xi. No. 50, 1857.) 4. COLIN : On the Digestion and Absorption of Fats without the Influence of the

Pancreatic Juice. (L'Union Médicale, t. xi. No. 50, 1857.) 5. DONDERS: On the Absorption of Fat in the Intestinal Canal. (Moleschott's

Untersuchungen zur Naturlehre, vol. ii. p. 102, 1857.) 6. KÖLLIKER: Remarks on the Absorption of Fat in the Intestinal Canal; on

the Eristence of a Physiological Fat-Liver in Young Animals; and on the Functions of the Spleen. (Verhandl. der Würzburg. Gesellschaft, vol. vii.

p. 174, 1856; and Schmidt's Jahrb., vol. xcii. p. 20, 1857.) 7. Von WITTICH: Contribution to the Doctrine of the Absorption of Fat.

(Virchow's Archiv, vol. xi. p. 37, 1857.) 8. MOLESCHOTT: New Proof of the Entrance of Solid Particles into the Conical

Cells of the Intestinal Mucous Membrane. (Moleschott's Untersuchungen

zur Naturlehre, vol. ii. p. 119, 1857.) 9. HOLLANDER: Contribution to the Researches regarding the Entrance of Small

Solid Bodies from the Intestinal Canal into the Blood. (Virchow's Archiv,

vol. xi. p. 100, 1857. Extract from an Inaugural Dissertation.) VERNOIS and Becquerel offer the results of the analysis of the milk of sixteen different breeds of cows, five of goats, one sheep, and one female buffalo, They infer from their observations, that the composition of the milk varies considerably with the country in which it is examined; the country where an analysis has been made ought therefore always to be stated. 1. While the cows of Paris and its neighbourhood give 36 to 37 parts of butter to 1000, those of the Tyrol, Switzerland, Holland, and those of the Angus-race yield 70 to 98 parts. 2. There exists an antagonism between the richness of the milk in butter and albumen, and the richness in casein and sugar; a difference which is so marked, that it allows a division into butter-cows and cheesecows (raches à beurre et vaches à fromage). 3. An analogous difference the authors found in the milk of women and of sheep. Here, too, the greatest degree of variation is found with regard to the per-centage of butter. 4. One cannot, in an absolute manner, declare one kind of milk superior to another;

but that of one breed may be preferable in a certain case on account of the larger quantity of butter, that of another in a second case on account of the greater richness in casein, that of a third may be chosen for its proportion of sugar, &c. Thus, the Angus-breed yields most butter, the Norman race most casein. 5. The quantity of food appears to be of considerable influence on the proportion of the different constituents; a large quantity seems to cause an increase of sugar and casein, a moderate quantity to induce an increase of butter and albumen. 6. The authors draw especial attention to the large per-centage of albumen (13 to 1000) in the milk of goats, as also to the richness of the female buffalo, in solid substances in general, and in albumen (13) and butter (80) in particular. Finally, Vernois and Becquerel express the opinion, that the milk of nurses of different climates may offer similar differences as that of different races of cows, according to the differences in soil, in food, &c., corresponding probably to the varieties in character and customs of different nations.

The fact that some fatty substances, when eaten, are almost entirely excreted by the alvine dejections, while the amount of fat in the fæces does not become increased by the moderate consumption of other fats, led Berthé to' the examination of the quantity of fat excreted with the fæces under the influence of various oleaginous matters administered to the same healthy subject in doses of from thirty to sixty grammes per diem. These experiments led the author to the inference, that there is a point of saturation of the body for most of the fatty matters, from whence almost the whole amount of fat ingested passes unassimilated through the intestinal canal. This point is arrived at after about twelve days with olive and almond oil, and almost all vegetable oils; after about a month with butter, whale oil, and English purified cod-liver oil (huiles de baleine et de foie de morue Anglaise, décolorées ou lavées); while the use of the pure brown cod-liver oil (huile de foie de morue brune et pure) did not lead to an increase of fat in the fæces, even when its use had been continued for more than a month. Berthé therefore proposes a division of the fatty substances into three groups :-1. Substances of difficult assimilation (olive, almond oil, &c.); 2. Assimilable substances (butter, whale oil, English cod-liver oil, and probably all animal fats); 3. Very assimilable substances (brown and pure cod-liver oil).

Corvisart confirms the observation of Purkinje and Pappenheim regarding the existence of a substance in the pancreas (pancreatine) endowed with the virtue of dissolving azotized constituents of food. The author contends that the pancreatic juice exercises its influence only on that part of the nitrogenous substances which has escaped the action of the gastric juice, producing a kind of albuminose similar to that resulting from the influence of the gastric juice. The reaction of the surrounding Auid, whether alkaline, neutral, or acid, is of no importance regarding the performance of this function of the pancreatic juice.' Corvisart further states that the active principles of the gastric and pancreatic juice (pepsine and pancreatine) counteract each other when mixed together; that in the normal condition this is prevented, a, by the pylorus; b, by the gastric digestion itself, through which the pepsin is consumed; C, by the admixture of the bile, which destroys the power of the pepsin.

Colin's experiments regarding the absorption of fats are made on cows, in which he considers the formation of pancreatic fistula, and the opening of the pancreatic duct, as easy operations. Comparing the contents of the thoracic duct obtained from cows in which a pancreatic fistula had been established, with that of others where the pancreatic juice was not removed, the author arrived at the inference, that after the elimination of the pancreatic juice, the fat is digested and absorbed in the same manner as in the normal condition. It will be remembered that the experiments of Lenz, Herbst, and otl ers led to the same result.

Donders, too, found that absorption of fat takes place without the influence of the pancreatic juice ; that, however, this process is assisted by the emulsifying power of the pancreatic fluid. Donders further refers, respecting the absorption of fat, to the results of Von Wistinghausen's experiments, that the passage of fat through animal membranes is much facilitated by their previous impregnation with bile. Microscopic observation leads the same author to consider the presence of canaliculi in the thickened walls of the epithelial cells of the intestines, as described by Funke and Kölliker, as highly probable.

Kölliker proved, by injection of oil into the rectum of a young cat, the possibility of the absorption of fat through the epithelial cells of the colon. He further constantly found fat in the epithelial cells of the stomach of sucking animals, but no white chyliferous vessels. He corroborates Brücke's obser. vation, that fat is absorbed by the follicles of Peser's glands, but does not offer decided proof in favour of the absorption of fat by bloodvessels.

Hollander repeated at Dorpat, under the superintendence of Bidder, some of the experiments of Marfels and Moleschott. "The authors injected in many instances the defibrinated blood of oxen, calves, and sheep, through an elastic tube, into the stomach of frogs; they continued doing this in the same animals for several days running, once or twice daily, but they never succeeded in finding any of the injected globules in the blood of the frogs. The essay shows that the experiments were performed with much care, but the negative result does not offer a valid objection to the permeability of the epithelial cells of the small intestines, as it appears more than probable that the blood-globules had undergone a considerable alteration under the influence of the gastric juice, before they reached the cavity of the jejunum and ilium.

Donders, likewise, in a great number of experiments, never succeeded in obtaining a proof for the passage of solid molecules through the epithelial cells of the intestinal tube.

Molescbott, on the other side, has repeated many of his former experiments, in order to find under which circumstances the entrance of solid particles into the cells takes place. Although he again obtained many positive results, principally when he had employed recently-precipitated particles of Berlin blue, yet he has hitherto not been able to ascertain which are the most favourable circumstances, or why the absorption takes place in one case, and not in several others.

Von Wittich contributes an observation of great importance regarding the question at issue. A rabbit killed (by bleeding) six hours after it had been bitten in the back by a dog, and thus deprived of the use of its posterior limbs, exhibited the chyliferous vessels, originating from the lower half of the ilium, filled with an entirely red fluid. This redness was shown to be caused merely by the admixture of the red blood-globules in a large proportion, not by that of colouring matter. The corresponding part of the intestinal tube contained mucus mixed with blood, after the removal of which the mucous membrane manifested the appearance of fine red dots, which, by means of a lens, were recognised as villi filled with blood. Von Wittich does not hesitate to explain this state of things by adopting the view, that the blood-globules pass as such through the epithelial cells and the parenchyma of the villi into the chyliferous vessels; he is of a similar opinion regarding the entrance of fat and other minutely-divided solid substances into the absorbent vessels. After various unsuccessful attempts, the author succeeded also, by means of the experiment, in proving the entrance of blood-globules into the chyliferous vessels of the cæcum, five hours after he had injected blood into that portion of the intestinal canal. Von Wittich agrees with Brücke and Moleschott, in opposition to Hyrtl and others, in attributing to the contraction of the muscular coats of the intestinal tubes much influence on the absorption of substances contained within its cavity.

39-xx.

16

II. BLOOD; RESPIRATION; CIRCULATION. 1. ZIMMERMANN : On Fibrin, and the Cause of its Coagulation. (Moleschott's

Untersuchungen zur Naturlehre, vol. i. p. 133, 1856.) 2. HARLEY: On the Chemical Changes of the Blood during Respiration. (Vir.

chow's Archiv, Band xi. p. 107, 1857.) 3. BERNARD : On the Elimination of Sulphuretted Hydrogen through the Surface

of the Lungs. (Archiv. Génér. de Méd., Fevr. 1857.) 4. HOPPE: On the Influence of Carbonic Oxide on Haniato-globulin. Prelimi

nary communication. (Virchow's Archiv, Band xi. p. 288, 1857.) 5. HOPPE : On the Influence exercised by Change of the Pressure of the dir on

the Blood. (Müller's Archiv, p. 63, 1857.) 6. VALENTIN: Contribution to the Knowledge of the Hybernation of Marmots.

(Moleschott's Untersuchungen zur Naturlehre, Band i. p. 206, 1856.) 7. ABERLE: On the Measurement of the Diameter of Arteries in Living Man.

(Dissert. Inaugur., Tübingen, 1856.) . 8. WAGNER, R.: On the Observation of the Circulation of the Blood, and the

Locomotion of the Chyle in Warm-blooded Animals. (Göttinger Gesels, der

Wissenschaft., No. 13, 1856 ; and Schmidt's Jahrb., Band xciii. p. 18, 1857.) 9. KUNDE: Physiological Erperiments on Apparent Death. (Müller's Archiv,

Jahrgang, 1857, p. 280.) Regarding the nature and origin of fibrin, Zimmermann repeats that he considers it as an excrementitious substance, exhibiting a certain stage in the metamorphosis of proteinaceous bodies, not any longer fit to serve in the nutrition of the organism. A small quantity of fibrin is regarded as a necessary constituent of the blood, but “the healthier the subject, the smaller the quantity of fibrin." By further oxidation, fibrin is, in the normal state, transformed into other excrementitious circumstances. “Sometimes, however," the author says, “the formation of fibrin takes place in so tumultuous and rapid a manner, that the transformation into excrementitious substances cannot take place; whence arises exudation of the accumulated fibrin, a process through which the blood is, for the time, purified of this substance. Later, when the cause for this abnorinal crisis has ceased, the fibrin may again be absorbed and otherwise excreted. Such is the case in pleuritis, pneumonia, &c." (p. 181.)

The coagulation is caused, according to Zimmermann, by the commencement of decomposition or putrescence; it is accelerated by the addition of substances in the state of transposition of elements, as pus or ichorous fluid from gangrenous wounds (Nasse), in the whole by all influences favouring putres. cence; it is retarded, on the contrary, by such influences as retard or prevent decomposition. The putrescence causing the coagulation of fibrin does not take place in the fibrin itself, but in other constituents of the blood, and principally in the red blood-globules. The chemical constitution of the fibrin passing into the solid state is regarded as remaining unchanged, with the exception of transposition of its atoms, effected by the contact with a substance in the state of decomposition, analogous to the transformation of casein by the action of rennet.

Harley describes some valuable experiments which he performed at Heidelberg in the laboratory of Professor Bunsen, and with the assistance of that distinguished chemist. After baving repeatedly shaken a certain quantity of blood with renewed portions of atmospheric air, until it was saturated with oxygen, and had given off as much carbonic acid as possible, he placed the blood thus treated with an equal volume of atmospheric air, in an hermetically-closed vessel, shook it frequently, and examined the air after it had been for a varying space of time in contact with the blood. In this manner the author found the air, after twenty-four hours' contact with fresh blood of oxen, to have lost

10:54 per cent. oxygen, and gained 5.05 per cent. carbonic acid. In another experiment with fresh arterial calves' blood, the minus of oxygen in the air employed was 9:63 per cent., the surplus of carbonic acid, 5.96 per cent. In both experiments, we meet with a greater loss of oxygen than is accounted for by the surplus of carbonic acid : the author inclines to the view that this remnant of oxygen is spent in the formation of water. Amongst Harley's experiments respecting the share which the various constituents of the blood exercise on the atmospheric air, we observe that those performed with fibrin lead to a result similar to that described by Scherer, * i.e., that fibrin has the power of absorbing a considerable quantity of oxygen, and of giving off carbon or carbonic acid. Albumen, too, was found to be possessed of the same property; but the quantity of oxygen absorbed, and that of carbonic acid excreted, are not so great as is the case in the experiment with fibrin. The comparative experiments with the coagulum and the serum of blood, manifest that the absorption of oxygen and the excretion of carbonic acid are larger in the former than in the latter case. Hæmatin was observed to exercise on the surrounding air the same influence as that ascribed by Scherer to the urohæmatin-namely, to deprive the air of a large amount of oxygen, and to enrich it with carbonic acid--a virtue which Harley attributes to the colouring substances in general, as well in the vegetable as in the animal economy.

Although the author's researches on the subjeot are not yet brought to an end, yet the experiments before us make it probable (in opposition to the view formerly maintained by Magnus) that a part of the oxygen admitted during respiration enters at once into a chemical combination with the various constituents of the blood.

The circumstance that sulphuretted hydrogen can be ingested in considerable quantity into the digestive canal without producing symptoms of poisoning, while the admixture even of so small a proportion as one part to 800 parts of air is sufficient, when inhaled, to kill a middle-sized dog, led Bernard to search, by means of experiments, for the cause of this remarkable difference. The injection of sulphuretted hydrogen gas into the jugular vein was rapidly fol. lowed by several deep inspirations and expirations, through which a large quantity of sulphuretted hydrogen was eliminated (proved by testing with acetate of lead); this process of elimination being completed within a few seconds. Similar was the effect when a concentrated solution of the gas was injected into the jugular vein. The ingestion of such a solution into the stomach was likewise followed by exhalation of the gas; but the interval between the ingestion and the exhalation was considerably greater, and the process of elimination lasted longer. Injection of the solution into the rectum led to an analogous result, sixty-five seconds having elapsed before the first traces of the sulphuretted hydrogen were discovered in the expired air.

The author alludes to the value of such experiments for the determination of the celerity of absorption, circulation, &c. . Thus the injection of the solution into the jugular vein led to dark spots on the test paper after three seconds; that into the crural vein only at the end of six or seven seconds; showing the greater space of time required for the transmission of the blood through a greater distance. The question, whether the whole amount of the sulphuretted hydrogen injected is exhaled through the lungs, Bernard is inclined to deny, as the injection of a small quantity into the arterial system of a dog did not cause the appearance of any gas in the expired air. This, however, took place when another injection was made soon after the first.

The observation made by Dr. Wolff, of Waldenburg, in Silesia, that the blood of labourers who had perished in coal-mines, and that of rabbits killed by means of carbonic oxide, are bright red, induced Hoppe to examine the change

• Scherer, in Liebig's Annalen, vol. xl.

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