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logical labours of the Royal Institute in France for 1815. (Thomps. Ann. June, 1816, p. 462.) gives notices of observations on the lynx, the leo cornuta, and the catoblas of the ancients. The first, Cuvier thinks was not the modern lynx, but the caracal; the two latter names belong to the antelope gnu, Linn. The five unicorns of the an: cients, he refers to the rhinoceros. The ancient asp, is the coluber haje, described by Geoffroy in his work on Egypt. The dolphins of the ancients were of two kinds, one our present dolphin, delphinus delphis, Linn. the other belonged to the sharks. The ancient fables respecting the hyaena and the ichneumon, Cuvier accounts for, by their peculiarity of conformation; the rigidity of the cervical muscles of the hyaena, often giving the appearance of continuous vertebrae. Cuvier's analysis proceeds to offer us observations on the musette, or musaraigne, on the anatomy of the moluscae, in particular of the anatises, the balanes, and the shells approaching the patellae, oscabria, haliotides, and ascidiae. M. M. Savigny, Des Marets, Le Sueur, and Lamoroux, have also pursued the subject of the pyrophoric sea animals (pyrosomata) lucernaria. Lamoroux has formed a system of the flexible, coralligenous polypi, which he has divided into 10 families, including nearly 50 genera, and 560 species. M. Le Clerc de Laval, has examined the confervae, and some microscopic animals. (Have not the confervae been found to afford an instance of a conversion of animals into vegetables? Some German author on the subject, whose name does not now occur to me, says so.)
M. de Latreille has described certain crabs of the Mediterranean Sca.
M. de Savigny has also treated on the anatomy of the scolopendrae, and some other insects.
M. de Labillardiere has presented to the Class some observations on the habits and economy of bees, and the circumstances under which they put to death or spare the male bees.
He and M. de Latreille have also presented observations on the coleopterous drill-insect, the vrillete, or death-watch; already described by Allen and Durham, 20 Phil. Trans. 376. and 22 Phil. Trans. 832. This animal is the ptinus pulsator, Linn. Durham has also figured and described another animal that beats; 24 Phil. Trans.
PHYSIOLOGY AND MEDICINE.
Dr. Wilson Philips, in a paper read at the Royal Society in January, 1816, has rendered it probable that the circulation of the blood and the action of the muscles are independent of the nervous influence, and that this influence only acted on the muscles like any other stimulus. But the case is very different with the secretions. Whenever the nervous influence is interrupted the secretion is at at end. Several rabbits had the eighth pair of nerves divided, and in all of them the parsley, which they ate after the operations, remained in the stomachs quite unaltered, and exactly resembled parsley chopped small with a knife. The stomach was also much"distended, and a portion of the food was contained in the oesophagus.
This was owing to the unsuccessful attempts which the animal made to vomit, which always follow the division of the eighth pair. The animal soon shows a violent dyspnoea, and seems to die at last of suffocation. Since the experiments of Galvani on animals, it has been a favourite opinion of many physiologists that the nervous influence is the same with galvanism. To put this to the test of experiment, a portion of the hair of a rabbit opposite to the stomach was shaved, a shilling tied on it, the eighth pair was divided, and the extremities of the nerve coated with tinfoil. These were connected with a galvanic battery of 47 pairs of plates four inches square. The trough was filled with a liquid composed of one part muriatic acid and seven parts water. This action was kept up for 26 hours. No dyspnoea took place, and after death the food in the stomach was found as much digested as in the stomach of a healthy rabbit which had eaten food at the same time. The smell of the parsley was destroyed, and the smell existed which is peculiar to the stomach of a rabbit during digestion. This experiment was several times repeated with the same result. So that it appears that the galvanic energy is capable of supplying the place of the nervous influence; and that while under it, the stomach digests food as usual. Mr. Wilson likewise made a number of experiments to show that heat is a secretion from the blood produced by means of the nervous energy. When new drawn blood is subjected to the action of the galvanic battery, it continues several degrees hotter than blood not subjected to the same process. . It should appear, that Mr. WilVol. I.
son has gone rather farther than his experiments will warrant, when he concludes that the nervous influence and galvanism are the same. It is clear that the section of the nerve interrupts the nervous influence. Mr. Wilson’s experiments (supposing them correct) show us that galvanism puts an end to this interruption. But it may do this merely by serving as a conductor to the nervous influence. On Thursday, the 1st of February, Dr. Wilson Philips’ paper was continued: he considers it as proved by his experiments that the ganglia communicate to the nerves proceeding from them the general influence of the brain and spinal marrow. Nerves proceeding from them supply all the involuntary muscles. But if this be the case, it will be asked, how comes the digestive power of the stomach to be destroyed by cutting the eighth pair of nerves, seeing that the stomach is supplied with nerves from ganglia? The eighth pair coming from the largest portion of the nervous matter possesses the greatest influence; but the digestive power of the stomach is weakened likewise by the interruption of the nerves proceeding from ganglia. This he proved by destroying part of the lower portion of the spinal marrow of different rabbits. In every case the digestive power of the stomach was impaired or destroyed; the urinary bladder and rectum lost the power of discharging their contents, and paralysis of the lower extremities ensued, and a great degree of cold took place. The heat of one rabbit before death sunk as low as 75°. Though the power of the stomach as an organ of digestion is destroyed by cutting the eighth pair of nerves, still its muscular power 3 I
remains; but it does not act as usual, because the stimulus of digested food is wanting; or it acts so as to throw the food out of the stomach the wrong way, in consequence of the unnatural stimulus of undigested food. On Thursday, the 8th of February, Dr. Wilson Philips’ paper was concluded. He showed that the heat of animals was in all probability owing to the nervous energy. He finished his paper with a general view of the facts which he had established in the three papers which he had laid before the Royal Society. The muscular energy depends upon the particular structure of the muscles; the nervous system is supported by the sanguiferous; but the sanguiferous can act without the influence of the nervous system. Secretion and animal heat are entirely dependent upon the nervous system. Hence the muscles cannot for any length of time continue to exert their energy if the nervous influence be cut off. The nervous influence appears the same with the galvanic energy. On an objection being made, that these experiments ought to have been repeated on other animals besides rabbits, Dr. W. Philips repeated them on dogs, with the same results. The experiments of Dr. Wells, Berzelius, and Mr. Brande, tending to show that the colouring matter of the blood is not iron, or any combination of iron, but animal matter, have been lately confirmed by the analysis of Vauquelin, to which, for want of room, I am obliged to refer in Dr. Thomson's Annals of Philosophy for September, 1816. Mr. Rose has discovered that the urine in hepatitis contains no urea; hence it has been supposed,
(I think prematurely,) that the only use of the liver is, to separate urea from the blood. But the phenomena of the gallstone, tend to support this opinion of Dr. Thomson. In Annals of Philosophy for April, 1816, is a statement of several facts by Dr. Balfour, Mr. W. H. Bailey, M. Percy, and M. Jos. Baronio, on the reunion of parts señarated from the living body, which appear to be incontrovertible. In the No. 2, and No. 3, of Brande's Journal, are two papers by Dr. Parke on the laws of sensation, which have great merit for the condensation of known facts, and the expression of known laws of the animal economy, though he is greatly indebted throughout, to Bichat’s views of the same phenomena. From the days of Aristotle to Locke and his followers inclusively, the motto has been, Nil unquam fuit in intellectu, quod non prius erat in sensu. However this may be, we must resort to physiology to account for sensation. According to Dr. Parke, sensations arise either from the impressions of external objects on our organs of sense, or from unusual states of the internal viscera, and organs of animal function. These sensations are modified either, 1st. By the object making the impression; or, 2d, By the state of the organ impressed; or, 3d, By the state of the sensorium; or, 4th, The general state of the system; but in all cases subject to regular laws, which govern the objects and the impressions. Sensations therefore, according to Dr. Parke, have been improperly confined to the impressions of external objects; wherein he is doubtless right. He considers mechanical distention as the only natural and habitual stimulus to muscular structure, and as the immediate cause of muscular action. Dr. J. Want has introduced Briony root as a remedy in dropsy, gout, and rheumatism. Four ounces sliced and infused in 8 ounces of white wine; the infusion to be taken at twice in two days. Sir Everard Home ascribes the action of specific medicines to their being received into the circulation. The eau medicinale D’Husson, which was at first supposed to be white hellebore, he considers as a vinous infusion of the roots of the colchicum autumnale or meadow saffron. Dr. J. Want thinks, it is a spirituous tincture of the roots of that plant, whereof he prescribes two ounces cut into small pieces, to be digested in four ounces of alcohol. I believe the usual dose is from 70 to 80 drops. It (that is, the medicine imported and sold under the name of Husson’s gout-drop, at 3 dollars for a vial full, containing 240 drops;) has been given in Philadelphia in cases of gout, and of gout complicated with dropsy, with very good effect. Mr. Brande having recommended (very properly) magnesia as a remedy in nephritic complaints, has published a paper on the ill effects produced by the inordinate use of it. It appears, that, when taken where the symptoms do not require it, and persisted in, accumulations of sandy matter, consisting chiefly of magnesia, are apt to take place in the bowels. This may be so occasionally, but I have seen magnesia long persisted in, when no indications called for it, without any bad effect: an acid diet for a few days, I should presume, would prove a remedy for the excess. The gout and the
stone have nearly the same sources, they are very apt to alternate, and they may be considered as varieties of the same disease, like fever and ague, and dysentery. The best prophylactic remedy I know applicable either to the one or the other, (premising moderate cathartics, with perfect abstinence from wine and acid drinks,) is, alternate doses of magnesia and Castile soap, the one on one day, and the other on the next. The soap may be taken to the amount of half an ounce in two doses. I have reason to believe, that attacks may thus be prevented which would otherwise have taken place. In the 3d No. of Brande’s Journal of Science and the Arts, page 199, is the very curious case of Col. Martine, who himself filed away by a file made of a knitting needle, or a watch-spring, a stone in his bladder. Dr. Bigelow, of Massachusetts, has published a very interesting memoir on the ergot of rye. This kind of damaged grain, (spurred rye,) has usually been supposed to produce (and probably when used as an article of food, does produce) the dry gangrene: in Massachusetts, the ergot is exhibited as a medicine in amenorrhoea, and to facilitate labour in pregnant women, to the amount of half an ounce aday. It is exhibited also in retention of the placenta, and in uterine haemorrhage, as is said with good effect. Electricity has been found useful in a case of aphonia. In a paper of Dr. Scott's, on the Arts of India, are some suggestions of the probable virtues of chlorine as a medicine; I take this opportunity of suggesting also, whether it might not be a very useful gargle, used in a weak state, (combined with water,) in cases of carious teeth, and ulcerated sore throat, and as an application to ill conditioned ulcers? its anti-contagious qualities would naturally lead to this employment of it.
Men of science are yet in doubt, whether the galvanic and the electric fluid are identical: the different processes for obtaining and exhibiting these fluids, (if indeed they be distinct) the different sensations they produce, the different effects they have upon natural bodies, the passage of the electric shock through a circle of persons, however extended, without sensible diminution; while the galvanic effect is hardly felt in the midst of a circle of a dozen persons,—these, and some other distinctive marks that might be enumerated, have excited doubts as to the identity of electricity and galvanism. The following curious experiment of Confiliachi, tends to prove that they are the same fluid.
Surround, says he, an active galvanic pile with moist leather, or some such covering, so as to create a resemblance to the organs of a torpedo inclosed in his skin: let the pile be interrupted in some part of it, or divide it into two columns placed near each other. Communicate a long metal wire with one, and another with the other pole of these piles, and let the distant end of each of the wires dip in water in some non-metallic vessel; these wires should be a few inches asunder in the vessel. Dip the hand in the water, and bring it in contact or very near to the wires; when a communication is made between the two columns by means of a good conductor, a shock is felt in the hand. Hence he concludes, that electricity and
galvanism are the same, the shock in question being similar to that of the Leyden vial. There are three theories afloat to account for electrical facts: Ist, Franklin's; one fluid, which may exist either in its natural quantity, in less than its natural quantity, or in more than its natural quantity; electric phenomena depending on the efforts of the fluid, or the substances that have an affinity for it, to regain its natural equilibrium when disturbed. 2. Du Fry's, Symmers; two fluids, vitreous and resinous; the one producing the effects ascribed to positive or surplus electricity, the other to negative or deficient electricity: this is nearly abandoned by modern electricians. 3. Sir Humphry Davy's; that there is no specific electric fluid, any more than a specific matter of heat; but that the phenomena arise from peculiar movements in the bodies affected by what is called caloric and electricity. An . opinion that does not seem well calculated to explain the phenomena in either case. It seems established that oxygen and its compounds are positively electrified: potassium, hydrogen, and combustible bodies negatively electrified. Bodies may be electrified, 1. By friction, as glass, sulphur, &c. these are bodies idio-electric. 2. By communication, as metals; an-electrics. 3. By heat, as the tourmalin; flyro-electrics. 4. By superposition, as in the pile of Volta, and that of Zamboni; sunafuto-electrics. 5. Bodies positively galvanic naturally, as oxygen, the acids, &c. which are attracted by the positive wire. 6. Bodies negatively galvanic naturally, as potassium, hydrogen, &c. which pass to the negative pole. J. P. Dessaignes has published