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and thus become blood-capillaries, and in their further passage sometimes join veins, sometimes lymphatics. The preparations, represented as successful injections, show not only the injected capillaries of sanguiferous, but also the injected serous vessels. Führer's second proposition, concerning the lymphatics, appears to have been adopted by the old physiologists in the seventeenth and eighteenth centuries.

Brown-Séquard's experiments, performed on various kinds of animals, with regard to their power of resisting asphyxia, prove:-1. That in new-born animals the temperature of their body, at the time of the experiment, is of great influence on the time during which they remain alive under conditions causing asphyxia; which conditions, in the author's experiments, consisted in submersion under water of 25° Cent. (77° Fah.) Thus, of four young dogs, one day and a half old, being of the same litter,

One having the temperature of 37° Cent. survived 19 minutes.

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2. Also, in adult warm-blooded animals, their temperature is of very great influence on the space of time during which they survive submersion. It appears, therefore, to be a general law, that the more the temperature of animals is lowered, the longer they are able to resist asphyxia. 3. The influence of the species of the animal on the time during which the asphyxiating agent can be endured, is much greater in young than in adult animals. On the whole, mammals, young and adult, survive longer than birds. 4. With regard to the influence of age, the author infers from his experiments, that it is less general than Legallois and Edwards had assumed it to be. In cats and dogs, it is true that the new-born animals survive three times as long as the adults; but the adult guinea-pig frequently survives longer than the new-born; the adult pigeon, too, survives in general as long as the new-born.

III. ABSORPTION; SECRETION; METAMORPHOSIS OF MATTER.

1. KÖHLER: On the Doctrine of Absorption. p. 401, 1859.)

(Virchow's Archiv, vol. xiv.,

2. FUNCKE: On the Endosmotic Qualities of the Peptons. (Virchow's Archiv, vol. xiii., p. 447, 1858.)

3. VALENTIN: On the Respiration after the Suppression of the Transpiration, and on the Reviving Influence of Higher Degrees of Warmth. (Archiv f. Phys. Heilkunde, Jahrgang 1858, p. 433.)

4. BROWN-SEQUARD: Note on the Existence of Rhythmic Contractions in the Excretory Ducts of the Principal Glands in Birds. (Brown-Séquard's Journal, vol. i., p. 775, 1858.)

5. HOPPE On the Circum-polarizing Quality of the Constituents of the Bile. (Virchow's Archiv, vol. xv., p. 126.)

6. KÜHNE: Contributions to the Doctrine of Icterus. First Communication. (Virchow's Archiv, vol. xiv., p. 310, 1858.)

7. BERNARD: On a New Function of the Placenta. (See Sub. VII.)

Köhler's communication on the absorption of poisons is the result of numerous experiments performed at the Physiological Institution of Marburg, under the superintendence of Nasse. The author endeavours to show the difference in the rapidity of absorption between starving and fed animals. The animals experimented upon were rabbits, dogs, and pigeons; the substances used, strychnia, hydrocyanic acid, and ether; the channels of introduction, the

digestive tube, the peritoneal cavity, the respiratory organs, and the subcutaneous cellular tissue of the back. The inference arrived at is, that starving diminishes absorption and retards the symptoms of poisoning and death. This result is contradictory to the views of many physiologists, but is analogous to that obtained by Kaupp in his experiments on the action of loss of blood on the phenomena of poisoning by strychnia. Köhler's experiments exhibit, it must be stated, frequent exceptions to the law he endeavours to establish, but in part these exceptions appear to depend on concomitant circumstances.

Funke proves by experiments on rabbits, that the absorption of the albuminpeptons in the digestive canal takes place with much greater rapidity than that of albumen. The author further shows that the quantity of albuminpepton passing within a certain space of time and under otherwise equal circumstances, through a filter of animal membrane, is considerably larger than that of albumen passing through it. Funke's experiments regarding the endosmotic properties of the substances in question finally demonstrate that the faculty of diffusion of the peptons is much greater than that of albumen. The endosmotic equivalent of the peptons is calculated at eight, that of albumen at 120. The addition of dilute hydrochloric acid diminishes the rapidity of diffusion of the peptons, and raises the endosmotic equivalent considerably. Alkalies in larger proportion increase the rapidity of diffusion and lower the endosmotic equivalent; in smaller proportion they have the opposite effect. These facts are of practical value, if we take into consideration the acidity of the fluids in the stomach, and their alkaline reaction in the small intestines.

Valentin caused suppression of the function of the skin in rabbits by covering the greater extent or the entire surface of their skin by glue or albumen. The author's experiments especially show the change thus produced in the phenomena of respiration and calorification, as also the beneficial influence exercised by a high degree of temperature in cases of suppressed function of the skin. If a rabbit, covered with a solution of albumen or glue, is kept in a temperature below 20° Cent. (68° Fah.), it appears at first not to suffer, but after from two to six hours it loses the power of standing; the respiratory movements become rare and almost imperceptible; peripheric irritation causes scarcely any reaction; the temperature of the rectum sinks from 39° Cent. (102-2° Fah.) to 20° Cent. (68° Fah.), and lower, the sinking being more or less rapid in the ratio of the surrounding temperature; the animal takes no food, and shortly dies. The diminution of the respiratory movements is accompanied by a very marked diminution in the quantity of carbonic acid exhaled; a stay of four hours in a temperature of 18° to 19° Cent. (64-4° to 66-2° Fah.), caused a reduction in the exhalation of carbonic acid to th of the normal amount, a stay of thirteen hours in a temperature of from 14° to 19° Cent. (57-2° to 66 2° Fahr.) to 1th of the normal amount, while the number of respirations had decreased to ths of the number before the application of the impermeable coat. The quantity of oxygen absorbed decreases likewise considerably, but not to the same degree as the exhalation of carbonic acid. Thus in one instance the proportion of oxygen absorbed to carbonic acid exhaled was (by weight) 0.72 to 1 before the experiment, while after the coating with glue and the stay in a temperature of 18° Cent. (64-4° Fah.), the proportion was 1-69 to 1. The urine contained in most cases albumen; the proportion of urea did not seem much altered. The post-mortem examination did not exhibit any striking changes; the serous effusions into the various cavities were by no means the rule (Fourcault); the glycogenic substance was found in the liver of only one animal. Remarkable is the change of phenomena under the influence of increased temperature. Animals coated with glue or albumen, which had offered almost the appearance of death, regain a great degree of liveliness, become enabled to stand on their legs, and often take again food;

their respiratory movements increase in frequency and extent, their warmth rises considerably, the quantity of carbonic acid exhaled is found to be much larger, and the proportion between absorption of oxygen and exhalation of carbonic acid in general almost normal. Hitherto, however, Valentin has not succeeded in keeping any of the animals coated with glue or other impermeable substances alive. Yet it cannot be denied that the author's experience regarding the effect of artificial warmth may be beneficially employed in the treatment of extensive burns, and also other complaints connected with suppressed action of the skin.

Brown-Séquard confirms Bernard's observation,* that the ductus choledochus and the ductus pancreaticus of birds contract in a rhythmic manner. The author has found the same phenomenon to take place in the ureters of birds, and especially during spring, on the vas deferens of adult birds. The contraction commences at the origin of the ducts, and extends gradually towards their termination. The rhythm of the movements is not the same in the four different kinds of excreting ducts. The celerity of the rhythmic movements of these ducts, just as that of the heart's contractions, is frequently increased by asphyxiating the animal. The destruction of the spinal centre is not followed by immediate cessation of these rhythmic movements. In mammalia Brown-Séquard has never found the rhythmic contractions of the excretory ducts, with the exception of the ureters.

Hoppe found that cholesterin and the various acids of the bile possess the faculty of circular polarization. The following are the figures for the rotation of the different substances, as observed by the author:

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Kühne's contribution to the pathology of icterus contains many experiments of physiological interest. By means of Hoppe's method, for the description of which we refer to the original, Kühne proved, first, that icterus, caused by closure of the common duct, is always attended by the excretion of biliary acids through the urine, besides the colouring matter of the bile; while normal urine does not contain biliary acids. He further found that the urine of icteric patients affected with closure of the ductus choledochus, does not exhibit any traces of hippuric acid; as also that in each case the ingestion of benzoic acid does not lead to excretion of hippuric acid, as it does in health, but that the benzoic acid is excreted as such. This fact, first observed in man, is corroborated by experiments on dogs. In a former essay the author has stated his view, that the transformation of benzoic acid into hippuric acid takes place by means of the glycocholic acid; the absence of this transformation in the cases in question lead him to the inference that the formation of glycocholic acid ceases after the closure of the common ducts-an inference which is supported by direct chemical analysis. Numerous injections of the salts of soda with the biliary acids into the veins of dogs had the constant effect of causing the passage of these salts, together with bile pigment, through the urine. In most cases the urine exhibited also traces of albumen, and in many hæmatin, without blood-globules. Some animals had, after the injections, convulsions of epileptiform nature. The regular appearance of the biliary pigment in the urine is ascribed by the author to the decomposition of

* Comptes Rendus de la Soc. de Biol., vol. i., p. 171. 1849.
† Conf. Sub. IV. of this Report.

Conf. this Journal, No. xliii., p. 229. 1858.

blood-globules and the transformation of hæmatin into biliary pigment, through the influence of the biliary acids. This view, it will be remembered, is contradictory to that of Frerichs, who inferred from similar experiments that the biliary acids were sometimes transformed within the organism into biliary pigment. Kühne shows, at all events, that the biliary acids possess the power of decomposing the blood-globules, and his further experiments render also his theory regarding the origin of the biliary pigment very probable. It is evident that this view, if correct, would support the theory that the liver is an organ in which the blood-globules are decomposed. In the report of the cases of artificial icterus, by ligature of the common duct, two phenomena are mentioned, which appear as yet not sufficiently explained-viz., that the skin of the dogs had no icteric appearance, although the urine was loaded with biliary pigment, and that in one of the dogs the urine became after some time deprived of biliary pigment, although the fæces remained uncoloured; that therefore the liver seemed to have lost its function of forming biliary pigment.

IV. NERVOUS SYSTEM.

1. WAGNER: Critical and Experimental Researches on the Functions of the Brain. (Zeitschrift f. rat. Med.; Third Series; vol. v., p. 215, 1859.) 2. NONAT: Facts tending to show that the Anterior Fasciculi of the Spinal Marrow are subservient to the Transmission of Sensitive Impressions. (Brown-Séquard's Journal, vol. i., p. 752, 1858.)

3. BROWN-SEQUARD: New Experiments on the Transmission of Sensitive Impressions in the Spinal Marrow. (Brown-Séquard's Journal, vol. ii., p. 65, 1859.)

4. VON BEZOLD: On the Crossed Action of the Spinal Marrow. (Zeitschrift f. wissensch. Zoolog., vol. ix., p. 307; and Schmidt's Jahrbücher, vol. i., p. 28, 1859.)

5. LISTER: Preliminary Account of an Inquiry into the Functions of the Visceral Nerves, with Special Reference to the so-called "Inhibitory System." (Proc. of the Roy. Soc. of London, vol. ix., p. 32.)

6. PFLUGER: Experimental Contribution to the Theory of "Inhibitory Nerves.” (Archiv f. Anatomie and Physiologie ;* Jahrgang 1859, p. 13.)

7. HABER: On the Action of Curare on the Cerebro-spinal Nervous System. (Archiv f. Anat. und Physiol., Jahrgang 1859, p. 98.)

8. BUDGE: On the Centrum Genito-spinale of the Sympathetic Nerve. (Virchow's Archiv, p. 115, 1859.)

9. WAGNER: Notes on some Experiments on the Cervical Portion of the Sympa thetic Nerve in a Decapitated Woman. (Zeits. f. rat. Med.; Third Series; vol. v., p. 331, 1859.)

10. ECKHARD: Preliminary Account on the Influence of the Irritation of the Sympathetic Nerve on the Secretion of Saliva. (Zeitsch. f. rat. Med.; Third Series; vol. v., p. 334, 1859.)

11. PFLÜGER: On a New Re-agent exhibiting the Axis-cylinder. (Arch. f. Anat. und Physiol., Jahrg. 1859, p. 132.)

Wagner urges the necessity of the combination of the clinical observation on man with experimental researches on animals, in order to arrive at a more exact knowledge of the functions of the various portions of brain. He especially requests pathologists to give more accurate descriptions of symptoms during life and appearances after death, pointing to the necessity of our universally using the same terms for the signification of the various portions of

This journal, which is the continuation of Reil's, Reil's and Autenrieth's, J. F. Meckel's and Johannes Müller's Archiv, since J. Müller's death, is edited by the well-known C. B. Reichert and E. du Bois-Reymond.

the brain. For experiments, the author recommends pigeons, and insists on the importance of ascertaining the weight of the whole brain and of the single portions; he proposes the following method:

"After the animal has been killed by suffocation, and the whole body has been weighed, the brain, with the origin of the olfactory nerves, and without the hypophysis (pituitary gland), is removed from the cranium by cutting through the chiasma of the optic nerves, and through the medulla two millimètres behind the calamus scriptorius. The brain thus taken out is then weighed, after which the following parts are removed and weighed separately:-1. The hemispheres of the cerebrum immediately before the thalami optici and immediately behind the commissura anterior, which remains attached to the hemispheres. 2. The mesencephalon (corpora quadrigemina, thalami optici, with the optic nerves cut off close to the origin of the oculo-motor nerves from the pons). 3. The cerebellum from the valvula-cerebelli anterior (valve of Vieussens), and cut off at the base of the inferior peduncles (crura cerebelli ad medullam). 4. The remaining piece of the medulla oblongata, the trunks of the cerebrum (Grosshirnstämme), and the origins of the cerebral nerves. Finally, the corpora quadrigemina are removed in the sulcus surrounding them from the mesencephalon, and again weighed separately." (p. 228.)

Nonat read in 1837, before the Academy of Medicine, a memoir, in which he asserts, as the result of repeated experiments, that the anterior and posterior fasciculi of the spinal marrow do not exclusively serve either motion or sensation, but that both convey sensation as well as motion. Nonat's experiments, at all events, proved that section of the posterior fasciculi does not cause abolition of sensation in the parts below the section. The author maintains at present the same view which he expressed in 1837.

Brown-Séquard's latest series of experiments lead to the corroboration of two important inferences communicated by him in former essays, but repeatedly contested since then by other physiologists (Chauveau, Schiff, &c.).† In a vigorous rabbit the author cuts first the roots of all the anterior nerves of the lower extremities and of the other lumbar pairs, and having convinced himself of a high degree of sensibility in the lower extremities, he cuts through the right lateral half of the spinal marrow at the first lumbar vertebra; the result is "that the right posterior limb is even more sensitive than before, while the left posterior limb has lost its sensibility." Other experiments areSection of both posterior fasciculi of the spinal marrow; result-the tactile sensibility and the other kinds of sensibility persist below the section: Section of the entire thickness of the spinal marrow in the dorsal region, with exception of the posterior fasciculi; result-the posterior limbs have lost the tactile sensibility, and all other kinds of sensibility. Brown-Séquard infers-1. That the conductors of the sensitive impressions of the limbs and trunk cross in the spinal marrow, and not in the brain, as was supposed; 2. That the posterior fasciculi of the spinal marrow do not seem to be subservient to the transmission of any kind of sensitive impressions to the brain, but that the central grey substance is subservient to the transmission of these impressions. Bezold thinks with Ludwig that the principal cause of the great discrepancy in the results obtained by various physiologists regarding the functions of the spinal marrow, lies in the fact that different men have experimented on different classes of animals, and each of them has generalized his experience. The author has therefore instituted separate series of experiments on amphibia, birds, and mammalia. I. In frogs the results arrived at are:-1. Sections of either -half of the spinal marrow from its commencement until immediately above the origin of the nerves of the lower extremities, exercise no influence on the motions of the limbs of the other side, nor do they produce any change in the * Conf. this Journal, No. xxxv., p. 233. 1856.

+ Ibid., No. xli., p. 241 (1858); and No. xliii., p. 230. 1858.

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