Transcript
Page 1: EFFECT OF ELECTRO-MAGNETISM ON THE ACTION OF THE HEART

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EFFECT OF ELECTRO-MAGNETISM ON THEACTION OF THE HEART.

By Dr. BUDGE, Lecturer in the University of Bonn.ALLOw me to communicate to you the following interesting

experiment, which I made in the presence of the ProfessorDr. Albers, Drs. Brach, Kuch, Kilian, Mayer, Wutzer,Neumann, Remak of Berlin, Wolff, and many others. Theresult of the experiment is invariable.

Let an electric stream, by means of a magneto-electricrotation apparatus, pass through the medulla oblongata of afrog, when the palpitations of the heart will cease as long astthe rotation is in action; and it will begin again, in the sameway as before the experiment, a few seconds after the rotationhas ceased. This experiment produces, in fact, tetanus in thewhole of the body. When any other part of the spinal marrowis exposed to the same electric stream, tetanus is equally pro-duced; but the-heart continues its movements without inter-Tuption. Finally, when the whole skin of the frog is subjectedto this stream, so that one wire lies close to the heart, tetanusin- the whole body is produced, but without affecting the heart.Directing the stream upon the ramus intestinalis nervi vagi,lying before the lungs, produces the same effect as uponthe medulla oblongata.Bonn, April, 1846.

REVIEWS.

Transactions of the Medical Societyof London.London. Highley, 1846.

WE are glad to see that this, the oldest public medicalsociety in England, has re-commenced the publication of anewseries of Transactions. Twenty-eight years have now elapsedsince the publication of the last volume of papers; and aftersuch a lapse of time, it can hardly be without the idea of re-peating it year after year, that the present volume has beensent forth. We hope this will prove to be the case. The

permanent record of,papers will stimulate their writers togreater care and labour than would be given to productionsintended to be merely ephemeral, and we should hope that afeeling of emulation between the. different societies will provebeneficial to them all.The present volume contains twenty-two papers, contributed

by the fellows of the Society, some of which manifest greatfalent, and all of them that solidity which might be expectedfrom well-educated men, most of whom are engaged in exten-sive practice.One of the most important papers is that of Mr. Pileher,

On the Nervous System, particularly the Excito-Motory,or Reflex Functions." Of this it is not too much to say, thatit is the clearest and most satisfactory exposition of the phy-siology of the spinal system which has ever been given in amoderate space. The proofs of the independent function ofthe spinal marrow are so cogently put, that we insert them intheir entire state:- .

" Even before birth, this function gives rise to those nu-merous, and often powerful, movements in utero, doubtlessexcited by irregular and undue pressure upon some part ofits body; during parturition, the little hand clasps the at-tendant’s finger, when placed upon, and gently pressing, itspalm; the mouth often closes upon the finger when thereintroduced; the leg is drawn up, away from the accoucheur’sgentle touch, increasing the difficulty of turning; facts wellknown to every midwife, and which assists them in determin-ing the life or death of the being: and who will presume tosay that these movements are mental, when multiplied factsdemonstrate that the mind is not evidenced for many daysafter birth ? 1 Parturition being completed, this action is calledinto operation by the stimulus of the air playing upon theinfant’s face and body, and respiration occurs; if the ordinaryapplication of the atmosphere be insufficient, the attendantblows upon its face, and a lusty cry responds; and, probably,the often wonderful effects of the warm bath are partly pro-duced through the medium of this function. Still later, theexcito-motory function is evidenced in the child’s sucking; inits startings upon a breath of air coming in contact with it;in the rapid retraction of its limbs upon the slightest touch; the

rolling its body, or its change in position, all during the deepestsleep, from which it is not the least aroused. Still further,the infant is suckled in its sleep, evacuates its bladder and itsrectum; and these actions are often artificially excited for thesake of cleanliness: the Jew priest takes advantage of thiscircumstance, and titillating the pubes and glans penis, in-duces evacuation of the bladder, previously to receiving thecircumcised portion into his mouth for the purpose of conse-crating it with holy wine. We cannot resist expressingadmiration at this wise and benevolent provision, by whichthe safety and growth of the infant and child are insuredbefore its mind is sufficiently developed to take cognizance ofbeneficial or injurious agents. The foregoing observations areequally applicable to the idiot, who, if the case be a completeone, lives a vegetable life only, is a mere automaton, whosewhole actions are excito-motory. Such a complete instance,however, is rare. I have certainly seen one, perhaps two; forgenerally some mind exists, the hemispherical ganglia notbeing altogether deficient; yet the anencephalous monster,during its short existence, performs many and constant excito-motory actions, in addition to its nutritive functions. Theexercise of this function in the total abstraction of the mind,as in walking, when all the mental operations are buried insome abstruse thought; in the flight of animals-when thevolition, having set the muscles in action, no longer is requiredto maintain the rapid motion, so that the operations of theirbrains may be entirely directed to the mode best adapted fortheir safety in escape, or their success in the chase. Thediseases of the excito-motory system are evidenced in itsloss of function; thus in general, disease of the spinalmarrow, whether idiopathic or secondary upon affection ofthe brain, is attended by complete suspension of motion.Often the,first, and for some time the only, symptom of affec-tion of the base of the brain, is unsteadiness in walking, inthe absence of unusual care or volition; on the other hand,an excited condition of this important function is recognisedin chorea, in many cases of convulsions of infants consequentupon intestinal irritation, so constantly mistaken for cerebraldisease, and therefore maltreated; in spinal epilepsy, so fre-quently confounded with brain affections, but which has itsseat in the chord, the organ being either idiopathically orsymptomatically influenced. It must have been noticed byevery practitioner, for the cases are of every day’s occurrence,that in affeotions of the base of the brain or the spinal mar-row, the true spinal chord, the motions of the limbs areregulated correctly enough during waking hours; but whenvolition is suspended by approaching sleep, excito-motorycontractions occur, and the catchings, as they are called, annoyand distress the patient, until, becoming exhausted, he fallsto rest, to become awakened by their return; or if he sleepon, the attendants perceive the action of the limbs or face,and the partial nature of the repose. Experiments uponliving animals prove the same facts; the partridge, shotthrough the head while upon the wing, still flaps its pinionsand pursues its way, undirected by the mind, till the shock iscommunicated to the whole system, when it drops; the pigeou,with its brain so carefully removed as to be insured againstloss of blood or general violence, will have its wings expanded,and fly; the eel, rendered, in like manner, brainless, swimsreadily upon its tail being gently grasped; the pup, similarlyprepared, will suck readily its mother’s dugs; the brainlessfrog has its legs quickly and powerfully moved, as in the actof swimming, upon the slightest irritation; the careful divisionof one par-vagum will embarrass the respiration of the rabbit,but it will still breathe through the operation of the oppo-site nerve, assisted by the common excito-motory; if bothpara-vaga be operated upon, death will be the inevitable con-sequence, though respiration may be continued for somehours, from the above noticed cause, notwithstanding the lateexperiments of M. Flourens. The experiment of this physio-logist on the fowl is a crowning example : with its entirebrain removed, its mind was annihilated-its senses were de-stroyed, but it swallowed food and drinks which were intro-duced into its mouth; it evacuated its excrement, breathedregularly, its circulation was perfect; in short, the great func-tion of nutrition was performed for, I think, nine months; inaddition to all this, it stood and walked when placed in theproper position, and probably would have lived on, had its foodnot been suspended by neglect. Experiments upon the re-cently dead animal produce similar effects; the applicationof a straw to the anus of the cat, just, but completely, dead,excites powerful action in the posterior extremities and thetail, such as the living animal would use to remove the irri-tant ; if the fore part of the body be excited, then the anteriorextremities will be moved; the eyelids will close upon touchy

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