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result, much greater than according to Valentin's, who found as the minimum for dogs 1: 4-93, as the maximum 1: 4:31.
Brown Séquard purposes to demonstrate, in a series of communications, the physiological properties of the red and of the dark blood, and especially to show that the properties and functions of these two kinds of blood depend principally on the oxygen and carbonic acid which they contain. We can scarcely give more than the author's inferences; for the arguments and experiments we must refer to the original. 1. The blood, he contends, possesses two distinct physiological properties-viz. that of nutrition, or of the production of the vital properties of the tissues; and that of stimulation of the organs and tissues endowed with vital properties. Thus, the author maintains that arterial blood owes to its oxygen the power of producing the vital properties of the nervous and contractile organs and tissues, to its carbonic acid the power of stimulating certain organs, as the heart, and perhaps also the medulla oblongata. Venous blood, on the contrary, does not possess the faculty of nourishing the brain, but is more able than the arterial blood to stimulate the heart and medulla oblongata, and still more so the pneumogastric nerves, the spinal marrow, the uterus, &c. 2. The essential difference between the arterial and venous blood, with respect to their physiological properties, is caused only by the different quantities of oxygen and carbonic acid contained in the two kinds of blood. Experiments made with venous blood charged with oxygen, and with arterial blood charged with carbonic acid, on muscles, as also on the brain and spinal marrow, have led the author to this inference. 3. All the contractile tissues can, after having completely lost their vital properties, recover them under the influence of oxygenized blood injected into their arteries. 4 and 5. The brain and all the nervous tissues can, after having completely lost their vital properties, regain them under the influence of blood charged with oxygen; 6. The longer muscular organs retain their vital properties after death-i. e. after the cessation of the circulation—the longer they remain able to recover them again, under the influence of oxygenized blood, after they had completely lost them. In general, it may be said, this space of time is longest when the temperature of the contractile organs and of the surrounding air is low, and longer in adult than in new-born animals. 7. The longer the nerves and nervous centres preserve their vital properties after the cessation of respiration or circulation, the longer they remain able to regain them under the influence of oxygenized blood. 8. In limbs separated from the body the muscular irritability may be under the influence of oxygenized blood, augmented to such a degree that irritation produces more effect in them than it had done in their normal condition. 9. Muscular irritability appears to be able to be maintained for an indefinite time in such limbs if one injects blood charged with oxygen.
Bernard has discovered-first, on the blood of the veins of the kidneys; later, on that of the veins of other glands-that this is sometimes as red as arterial blood, at other times as dark as the darkest venous blood. Further observations and experiments have convinced this author that the blood passing from the glands is red while the organs are performing their function; that it is dark while they are in a state of rest. It is evident from these facts, that the signification red and dark blood ought not to be considered identical with arterial and venous blood. Three interesting experiments are annexed to this communication. The first shows that the venous blood from the submaxillary gland becomes red, flows in increased quantity, and in distinctly jerking motion, when the nerve supplying the gland is galvanized. At the same time it was observed that the red venous blood lost, by standing, sooner its redness than the arterial taken from an adjacent artery of the same animal. From the third experiment we see, that tying the sympathetic branch going to the submaxillary gland causes the blood to become red and flow in large quantity, while no saliva is excreted; that galvanizing the sympathetic branch renders the blood dark, diminishes the quantity, and makes it even cease to flow. Through the same experiment we further learn that the galvanizing of the filament derived from the lingualis effects an abundant secretion of saliva, together with an increased flow of red blood.
Brown-Séquard confirms Magendie's observation, that the blood-globules of birds, when injected into veins of mammalia, disappear from the blood of these animals within one hour's time. He promises further information regarding the changes which the oval blood-globules undergo before disappearing. The author contradicts, however, Magendie's assertion, that the blood-globules of mammalia disappear almost immediately from the blood of birds, as he found them in large quantity on the day after transfusion, in much reduced proportion after a few days, and some isolated round globules even in the third week. It will be remembered that Marfels and Moleschott have traced the globules of sheep's blood in the blood of frogs several weeks after the injection.*
* Moleschott's Untersuchungen zu Naturlehre, vol. i. pp. 52–60. 1836.
With the view to test Frerich's theory of uræmic intoxication, Hammond performed two series of experiments on dogs. In the first series he injected into the veins of sound animals sixty grains of each of the following substances-urea, urea and vesical mucus, carbonate of aminonia, nitrate of potash and sulphate of potash; in the second series he injected the same substances, after having previously extirpated the kidneys. From these experiments the author concludes:-That urea (simple or combined with vesical mucus), carbonate of ammonia, and sulphate of potash, when injected into the blood vessels of sound animals do not cause death. 2. That nitrate of potash, when thus introduced, is speedily fatal. 3. That death ensues from the injection of any of the above-named substances into the circulation of animals whose kidneys have been previously extirpated. 4. That in neither case does urea, when introduced directly into the circulation, undergo conversion into carbonate of ammonia.
Ludwig and A. Spiess found that the temperature of the saliva excreted under the influence of electric irritation of the nerve is about 1° C. (i.e., 1·8° F.) higher than that of the blood in the carotid close to the salivary gland. The experiments were made by means of a thermomultiplicator, for the description of which we refer to the original. The result just mentioned proves, at all events, that the act of secretion is one of the sources of the warmth for the organism.
Martins availed himself of a journey to the Faroe Islands and to Spitzbergen to examine the temperature of various families of the order Palmipedes (Uria, Porcellaria, Larus, Anas, &c.). In looking over the table giving the average temperature of the various families and species of Palmipedes, living in the North of Europe, we are struck by the low temperature of the Porcellaria glacialis, being only 38 76° Cent. (i.e., about 101.77° F.) especially when we compare it with that of Anser cygnoides 42.84°) i.e., about 109-11° F.). This great difference of about 7:34° F. in animals nearly related must astonish still more, if we think of the energetic swimming and flying powers of the porcellaria glacialis.
Brown Séquard confirms the fact, that in general the temperature of sea birds, and particularly that of the genus porcellaria, is lower than that of other birds. This physiologist offers the hypothesis, that the long fasting to which sea birds are frequently exposed, may in part explain this phenomenon.
IV. SECRETION; EXCRETION; METAMORPHOSIS of Matter.
1. FUNCKE: Contribution to the Knowledge of Cutaneous Transpiration. (Moleschott's Beiträge, vol. iv., p. 56, 1858.)
2. MOSLER: Researches on the Passage of Substances from the Blood into the Bile. (Virchow's Archiv, vol. xiii., p. 29, 1858.)
3. FIGUIER: On the Formation of Sugar after Death in the Liver of Animals.
Méd., vol. xi., No. 79, 1857.)
4. BECQUEREL: On the Non-existence of Albumen in Normal Urine, and the Insufficiency of Chloroform as a Reagent on Albumen. (L'Union Méd. vol. xi., No. 144, 1857.)
5. GIGON: On the Inferiority of Phosphoric Acid as a Reagent on Albumen, and on the Reality of the Normal Albuminuria. (L'Union Méd., vol. xii., Nos. 12 and 13, 1858.) 6. KUHNE and HALLWACHS: On the Formation of Hippuric Acid after the Ingestion of Benzoic Acid. (Virchow's Archiv, vol. xii, p. 386, 1857.)
7. KUHNE: On the Metamorphosis of Succinic Acid. (Virchow's Archiv, vol. xii., p. 396.)
Funcke communicates valuable researches on the physiology of cutaneous transpiration The method of obtaining the excretion was that used by Schotten, viz., to wrap up the arm in a wide sleeve of India-rubber, and cause an increased excretion by various degrees of muscular action under varying external influences. The quantity of the excretion was found to be very variable, as well in the same person under various external influences, as also in different persons under the same external influences. The author calculated the quantity o sudoriparous excretion within an hour to vary between 53 040 and 815:337 grms., that c solids between 0-923 and 6.967 grms. The proportion of solids dissolved in the fluid (i.e exclusive of epithelium), varied from 0.696 to 2.559 per cent., and in general the law wɛ confirmed, "that the relative amount of solids exhibits an inverse proportion to the amour of excretion." With regard to the solids alone, the proportion of inorganic salts increased i the same ratio as the total amount of solids decreased. The most important result of Funcke
experiments, however, is the corroboration of the normal existence of urea in considerable proportion in the healthy cutaneous transpiration, a fact which had been denied by Schottin, who, it will be remembered, found it in so large a quantity on the skin of cholera patients.
Mosler performed some experiments with the view to determine which of the substances introduced into the blood may be traced in the bile. After having produced biliary fistulas in dogs, the author injected various substances into the blood. 1. By injection of lukewarm water into the crural vein, he proved that albumen does not pass so rapidly into the bile as into the urine; that, however, dilution of the blood causes an analogous alteration in the secretion of the bile to that described by Kierulf with regard to the secretion of the urine.* 2. Injection of grape-sugar showed that the quantity of grape-sugar in the blood, sufficient to effect its passage into the bile, must be still greater than that causing its admixture to the urine. Cane-sugar was found to pass more easily into the bile than grape-sugar, an injection of 40 grms. of the former being sufficient, of 70 grms. of the latter. 3. The introduction of even a moderate quantity of iodide of potassium into the blood leads to the entrance of this substance into the bile, from which however it soon disappears again. 4. Nitrate of potash introduced, as also the former, through the mouth, is soon discovered in the urine, but not in the bile. 5. Sulphate of copper, given by means of a pill, was in one instance distinctly traced in the bile. 6. Calomel did not enter so readily into the bile, nor did it effect such an increase in the quantity secreted as is generally supposed. 7. Sulphate of quina was never found in the bile. 8. The same was the case with benzoic acid. 9. After the administration of oil of turpentine, the bile assumed a peculiar resinous smell, which, however, was not identical with the violet odour of the urine.
Figuier communicates experiments, the result of which, according to the author's opinion, di-proves the formation of sugar after death in the liver of animals. He explains the opposite results obtained by Bérard and others, by the supposition that the livers had not been sufficiently washed out. The livers of three horses, after having been washed out during two hours and a half, did not yield a trace of sugar after a lapse of twenty hours. In three other examinations, the livers, after a stream of water having been passed through during an hour and a-half, exhibited still a notable amount of glucose, which was not found augmented after these organs had been left for twenty-four hours. Figuier promises to prove that Bernard's glycogenic substance is nothing but albuminose.
In contradiction to Gigon's assertion, that normal urine contains albumen, and that chloroform is the best test for it.t A. Becquerel states:-1. That not only albumen, but also other organic substances, and principally mucus, form an emulsion with chloroform, and that it is the presence of mucus, and not of albumen, in normal urines, which causes the production of an emulsiform precipitate by the addition of chloroform. 2. That normal urines contain no trace of albumen. 3. That chloroform is a very untrustworthy test for albumen.
Gigon, on the other side, repeats his former assertion, that chloroform manifests, under all circumstances and without exception, the presence of the smallest traces of albumen, that it precipitates it even when only one part is contained in 40,000 of fluid, while in a much less diluted solution no precipitation takes place by boiling, addition of nitric acid, pyrophosphoric acid, creosote, tannic acid, or any other reagent hitherto used for the purpose. With regard to pyrophosphoric acid, especially recommended by Becquerel as the most delicate reagent, Gigon remarks, that it does not show the albumen when the solution is more diluted than one to two thousand. The author gives then the result of the examination of two specimens of normal urine, of which the one yielded for twenty-four hours the quantity of 26 grms., the other 1.71 grm.
Kühne and Hallwachs endeavoured to find in which part of the system the transformation of benzoic acid into hippuric acid takes place. Injection of a solution of benzoic acid into the veins of dogs was not followed by excretion of hippuric acid through the kidneys; prevention of the entrance of bile into the digestive tube, by means of biliary fistula, did not prevent the transformation of benzoic acid when it was injected into the stomach; prevention of the formation of bile in the liver, through a ligature round its vessels, caused prevention of the transformation of benzoic acid; injectionin to the veins of dogs of a solution of benzoic acid mixed with the constituents of the bile, was followed by excretion of hippuric acid with the urine. The authors infer from these results, that the transformation does not take place in the alimentary canal, nor in the whole of the vascular system, but in the vessels of the
Cons. this Journal, No. xxv., 1854.
+ L'Union Médicale, Oct. 1857.
liver; therefore in blood mixed with the constituents of bile, and especially at the expense 'of the glycocholic acid, the glycin of which unites with benzoic acid to form hippuric acid by giving off two equivalents of water.
Kühne confirms, by experiments made on himself, the observation of Buchheim* and Piotrowsky, that the ingestion of succinic acid is followed by the excretion of hippuric acid in considerable amount through the kidneys.
V. NERVOUS SYSTEM.
1. SCHIFF: On the Function of the Posterior Fasciculi of the Spinal Marrow. (Moleschott's Beiträge, vol. iv., p. 84, 1858.)
2. BROWN-SEQUARD New Researches on the Physiology of the Spinal Marrow. (Brown Séquard's Journal de la Physiologie, vol. i., p. 139, 1858.)
3. BROWN-SÉQUARD: Influence of either Lateral Half of the Spinal Marrow on the corre sponding Half of the Brain and Face. (Brown-Séquard's Journal, 1. c., p. 241.)
4. BROWN-SEQUARD: Causes of Death after Extirpation of the Vital Point. (BrownSéquard's Journal, 1. c., p. 217.)
5. AUBERT and TSCHISCHWITZ: On the Arrest of the Diaphragm through the Pneumogastric Nerves in the Contraction and Relaxation. (Moleschott's Beiträge, vol. iii., p. 272, 1857.)
M. Schiff records some important points on which he is at variance with Brown-Séquard, 1. While the latter denies that the white posterior columns convey sensitive impressions to the brain, Schiff is led by his experiments to the inference that the white posterior columns, and these alone, conduct the impressions of touch; while the perception of common sensation -i.e., pain through stronger mechanical, chemical, or thermal agencies, cannot be produced by the posterior columns alone. 2. The grey substance conducts the impressions of co umon sensation-pain caused by strong pressure, burning, vulneration, &c. The perception of mere touch is not conveyed by the grey substance. 3. After the section of one half of the spinal marrow, or of both posterior columns, simple touching is not felt any more, but stronger impressions on the respective parts of the body are felt as pain. True hyperesthesia, as contended by Brown-Séquard, does therefore, according to these inferences, not exist.
Brown-Séquard, on the other side, adheres to his former assertions. He further relates experiments performed with a view to explain cases of paraplegia from disease of the spinal marrow with persistence of sensibility. The result of these experiments tends to show that every small portion of the conducting part of a lateral half of the spinal narrow contains conducting elements for the sensitive impressions coming from all points of the opposite side of the body situated below that small portion of the spinal marrow; and that impressions from any part of one lateral half of the body are transmitted to the brain by conducting elements distributed over all portions of the conducting part of the opposite lateral half of the spinal marrow.
The same author communicates that section of either half of the spinal marrow in the lumbar region is frequently followed, after some time, by convulsive winking of the eyelids, as also by twitchings of the other muscles of the face on the same side, by increased secretion of mucus from the corresponding half of the nose, sometimes also by disturbed nutrition of the eye of that side. He infers from these observations, that through the section of the spinal marrow an impression is propagated to the corresponding hemisphere in a manner different from that in which sensitive impressions are transmitted, as these pass to the opposite side.
Brown-Séquard states, that extirpation of the small portion of grey substance on the point of the calamus scriptorius, which Flourens called "point vital," does not necessarily produce immediate death; that the latter, if it takes place, is induced by the sudden arrest of the actions of the heart, which depends on the irritation of the medulla oblongata; that after the section of the pneumogastric nerves, the extirpation of the vital point does not produce the sudden arrest of the heart's actions; that the stoppage of the respiratory movements sore times observed, is not the effect of the removal of this small portion of grey substance, but of the irritation of the spinal marrow acting like the galvanization of the pneumogastric nerves that respiration and circulation may continue for days after the extirpation of the portion in
Archiv für Physiol. Heilkunde, p. 142, Jahrgang 1857.
question; that this is, therefore, not the prime mover of the respiratory mechanism, nor the centre of the "vital force."
The numerous experiments of Aubert and Tschischwitz performed on rabbits lead the authors to the following inferences:-1. That very weak streams of electricity cause in general a predominance of the contractions of the diaphragm, accompanied by either very frequent and small, or by rare and deep inspirations. 2. That streams of moderate strength produce the arrest of the diaphragm in the state of contraction—i. e., inspiration. 3. That strong streams lead to arrest of the diaphragm in the state of relaxation-i.e., expiration; that they cause at the same time relaxation of the heart. 4. That the whole diaphragm is influenced, even if only one pneumogastric nerve is irritated. It will be observed that these results tend to explain the opposite assertions of other experimenters-Traube, Lindner, Kölliker, Müller, and Snellen having found this arrest to take place in the state of contraction; Eckhard in the state of relaxation.
1. GRAFFE: Remarks on Various Subjects. (Gräfe's Archiv, vol. ii., Abth. ii., p. 299; and Canstatt, 1.c., p. 11.)
2. HELMHOLTZ. (Physiological Optics, 1855; and Canstatt, 1. c., p. 55.)
3. SCHULTZE: On the Mode of Termination of the Olfactory Nerves. (Monatssch. d. Berlin Akad., Nov. 1856; and Schmidt's Jahrb., vol. xciv., p. 169.)
Gräfe describes a case of importance for the doctrine of accommodation-namely, a complete paralysis of all six muscles of the eyeball without diminution of the faculty of accommodation. In another case Gräfe observed a spasmodic condition of the apparatus of accommodation, finding it, after an injury to the eye, constantly in a state suited for near objects, with inability to see distinctly distant objects.
Helmholtz gives, in his 'Physiological Optics,' a description of the eye which contains new information on several points-as the diameter of the curvature of the cornea, the lens, the distance of both surfaces of the lens from the vertex of the cornea, &c. We are, however, prevented from entering on these subjects.
Schultze's researches are performed on the representatives of all classes of vertebrate animals. They lead to a result which is not quite in accordance with that obtained by Ecker and Eckhard. The author shows that the terminating fibrils of the olfactory nerve are in no anatomical connexion with the epithelial cells; that they penetrate, however, between the cells to the free surface of the mucous membrane; offering thus a striking analogy with the termination of the optic and acoustic nerves.
VII. ORGANS OF LOCOMOTION.
1. DEITERS: De Incremento Musculorum. (Dissert. Inaug. Bonnæ, 1856; and Caustatt, 1. c., p. 105.)
2. AUERBACH: On the Tonus Muscularis.
statt, 1. c., p. 118.)
3. HEIDENHAIN: On the Tonicity of Muscles. statt, 1. c., p. 118.)
(Bericht. d. Schles. Gesellsch., 1856; and Can
(Physiolog. Studies, Berlin, 1856; and Can
4. HEIDENHAIN: Restoration of the Exhausted Irritability of Muscles by Continuous Galvanic Streams. (1. c., and Canstatt, l. c., p. 118.
5. MATTEUCOI: Researches on the Physical and Chemical Phenomena of Muscular Contraction. (Comt. Rend., vol. xlii. and vol. xliii.; and Canstatt, 1. c., p. 16.)
6. VALENTIN: The Action of Contracted Muscles on the Surrounding Air. (Archiv f. Physiol. Heilkunde, Jahrgang 1857, p. 285.)
7. MATTEUCOI: On the Conditions which Influence the Duration of the Muscular Contraction after Death. (Compt. Rend., vol. xliii.; and Canstatt, 1. c., p. 16.)
8. BROWN-SÉQUARD: On the Laws of Muscular Irritability, Cadaveric Rigidity, and Putrefaction. (Compt. Rend., vol. xlv., Oct. 1857.)
* Beiträge zu Anat. und Phys. Giessen, 1855.