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have directed its use, both internally andexternally, in a number of cases that havefrom time to time claimed my professionalconsideration, with the happiest and mostunequivocal success." EBERLE supposes itto be the most efficacious remedy we pos-sess in cases which are attended by an irri-table, quick, but weak pulse, with swelledjoints, and unattended by any great pain,unless on being moved.

Notwithstanding these high testimonials,I do not think that stramonium has had afair trial in this country ; I have frequentlyhad occasion to employ it, and am most

willing to speak of it as an important andvaluable remedial agent. I think I haveseen more relief afforded, in some painfulaffections, by an extract of stramonium,than either by belladonna or hyoscyamus.Generally, where some degree of fever hasbeen present, which would have made mehesitate to employ either those herbs oropium, I have administered it with greatsatisfaction to myself. The smoking sti*a- Imonium, in various states of difliculty ofbreathing, seems to have been the theme ofmore medical consideration in this countrythan either its internal administration or itsexternal application, for the Americans re-commend it in burns, haemorrhoids, psora,and other cutaneous affections; I shall,therefore, defer till my next lecture enteringupon a subject which is very interestingto us.

LECTURESON THE

PHYSIOLOGY OF THE NERVOUS

SYSTEM,DELIVERED IN 1836, IN THE COLLEGE OF FRANCE.

BY M. MAGENDIE.

LECTURE XIX.SMELLING, SEEING, AND HEARING. Prerious

experinzerats on smell. (pathology of the" rot.") Appm’ent reusons why It recent

experiment nlrpeured to demonstrate that theintegrity of the olffictot-y ncrees tt’ttS not es-sential to smell, lllocle of demonstrating, Ùzthe pigeon, the decussation of the opticnares. Experimentul destruction of thewhole of the anterior lobes of the cet’ebl’lu/l,Divisions qf the auditory apparatus, Anu-logies attempted to be found between tht,nerves of hea1’Îng ancl 4eeing. Anutozrciculdisposition of the acoutic nerve, Hearingprobably not delrenatant on a special acousticnerve. lllflltenceofthejifth pair ozer hertrwing. General insensibility of the ticoustitnerve.

GENTLEMEN:—You bear in mind, I trust,the results we obtained from our experimentsou the nerves connected with the organ oi

vision, and the pathological considerationswe laid before you as flowing from the phy-siological facts observed. Certainly, this

organ presents several phenomena whichwe were compelled to leave without expla-nation; but we pointed out the only methodwhich can ultimately lead to a discovery ofthe truth, and console ourselves with theidea that by assiduously pursuing that pathwe may at some future time arrive at theknowledge which now escapes our meansof investigation. However this may be,wehope at least to have been useful in pointingout the erroneous ideas, and still more er-roneous hypotheses, entertained on severalof the most important points of the doctrineof vision, and so far have done good, for theremoval of error facilitates wonderfully the

progress of truth.Having now examined the senses of smelland vision, let us pass to that of hearing;but before we enter on our subject allowme to follow my old custom of examiningbefore you some of the animals on whichwe experimented during the preceedinglectures. Here is the body of a young dorin which, if you remember, we endeavoured,some days back, to destroy the bulbs of theolfactory nerve. Notwithstanding completedivision of the nervous trunks, and destruc-tion of that portion of the cerebral massfrom which they spring, the sense of smellremained, as was proved by the animal’ssensibility when we passed a flask of am-monia under his nostrils. You may alsoremember that he even seemed to smell abit of cheese enveloped in linen, and placedat some distance. To prevent error, whichmight possibly arise from the animal beingguided towards the packet by his sight, wecovered the eyes with a bandage, yet he wasguided to the odoriferous object by the senseof smell; even this precaution did not con-tent me; to be more sure of the fact, Iemptied both eye-balls; two days after-wards the animal continued to distinguishobjects by the smell. You might naturallyimagine that the death of the animal beforeme was occasioned by the injury inflictedon his brain ; but no such thing, he died ofwhat is vulgarly called the " rot," a diseasewhich the researches I have made induceme to consider to be an inflammation of thegastro-pulmonic mucous membrane, veryanalogous to that we observe in the humansubject. The essential circumstance of thisdisease is the obstruction which occurs in

the pulmonary circulation, giving rise in

man, as well as in animals, to all the symp-toms depending on a non-oxygenation of the

blood. In the present case examination oftlte chest and abdomen fully bears out thedefinition I have just given of the disease

in question. Look here how the lungs are, solidified, hepatized, as the physician wouldsay : the whole substance is impervious,andFincapable of transmitting the circulating

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fluid in sufficient quantity for the support of The experiment, then, is not so decisivelife. as it might have been; but are we to admitTo return, however, to the more immediate the explanation which some amongst you

subject of our studies. Here is an animal will now doubtless hazard, viz., that thewhich preserved the sense of smell several function of smell was performed by thedays after the complete destruction of the twoortliree nervous filaments which escapedolfactory nerves, and which would, pro- the edge of the instrument ? I cannot agreebably, have continued to exist, notwith- with you in this; for if we suppose that thestanding the severe injuries necessarily pro- olfactory nerve be the only true nerve ofduced by the experiments performed on it. smell, how account for the function havingBut you may ask me, How are you sure survived after the immense injury the nervethat the olfactory nerves were completely sustained in the case now before us. Onedivided ? Perhaps the destruction of the would imagine it should destroy the func-bulbs was only partially effected. This tion altogether ; at least it must have modi-is a question which we cannot answer be- fied it more or less profoundly ; yet, if youforehand ; let us, therefore, have recourse remember well, the animal exhibited noto an examination of the brain, which will lesion whatever of the sense of smelling.resolve every doubt upon the point. In the The result of what we have just seen, Gen-meantime call to mind the manner in which tlemen, renders it necessary that we shouldthe experiment was performed, and I think perform this experiment once more beforeyou will have little hesitation in supposing you ; though one of the most striking andit satisfactory: a cutting instrument was remarkable that we have as yet had thepassed from right to left, a little above the honour of showing you, it will requirelevel of the base of the anterior lobe, and all further proof to satisfy the minds of thosethe parts included between the knife and who may still remain incredulous. Whenhard parts were completely divided ; the experiments are performed on livinganimalssame thing was done on the opposite side, so you must not expect to succeed on everythat it was almost impossible for so tender a occasion; and, above all, you must proceedstructure as that of the olfactory nerves to with a reserve and caution, in inductions, ofescape. But why lose our time in con- which but a few are capable; it was forjectures when facts are before us ? I now this reason I said in my introductory lectureraise up the anterior lobes, and the first that the difficulties of experimenting on

thing I discover is a deposit of grey matter living animals are so great that many phy-occupying the place of the nervous filaments siologists turn from them with disgust afterin the ethmoidal fossæ; I now proceed to a few trials, while a still greater numberdetach the anterior lobes of the brain, and exclaim against the utility of a means whichascertain more exactly if the nerves have they are equally incapable of employing orbeen completely divided, as we imagine, of appreciating.Ha ! I fear that a small portion of the ex- I shall speak, on another occasion, of theternal edge of the nerve has not been divided, rabbit in which we divided the opticand in this respect the separation of the nerves; in the meantime let me direct yourtrunk from the centre of the nervous system attention to the pigeon now before me..’ Inwould not be complete. Perhaps, after all, the bird tribe it is easy to demonstrate hy-it is only a portion of the pia mater ; let us siologically the decussation of the’ opticsee. No; it is the external edge of the nerves, by a very simple experiment. Younerve which escaped the action of the cut- have only to deprive the animal of one eye,tittg instrument. I pray you, Gentlemen, and then examine the results of this injuryto verify this fact by examining the brain on the internal apparatus of vision. Whenfor yourselves; see how nearly all the other you destroy the right eye, and allow thefilaments of the nerve have been divided, animal to live for some time, you will findexcept this little thread at the external that the trunk of the optic nerve, beyondborder. Experiments are useless, unless the point of decussation, or, in other words,their results be announced with the most between that point and the origin of theperfect frankness, and I trust that you will nerve from the brain, has become atrophied.never find that an absurd and culpable We performed this experiment on the pigeonccnaotcr-puopre will prevent me from declaring about fifteen days ago, but instead of de-the whole truth. Here the medium of com- stroying the animal to examine the state ofmunication between the external world and his optic nerves, we will perform anotherthe brain is extremely small, extremely in- experiment, which consists in destroyingsignificant; but still it is enough to prevent the whole of the anterior lobes of the cere-us from saying, as we thought a short time brum; this operation equally produces lossago, that the separation of the olfactory of vision; but a far more curious fact thatbulbs from the anterior lobes of the brain you will have occasion to witness is, thatwas complete; there still remains, as you the bird may survive weeks, or even months,may see here, a very small portion of the after this immense destruction of the cere-external edge of the right bulb ; the left one bral mass, capable of walking about, takinghas been much more completely destroyed, food, and, in a word, executing all the fune-

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tions necessary for the support of existence. Not content with twenty-four, some au-

In one of our next lectures you shall ex- thors contend that the skull is a vertebræ;amme the optic apparatus of this bird, and others again, unwilling to be outdone iuthe condition of its brain ; at present I will discoveries of this kind, would add the pel-merely add, as a conclusion, that if we had vis to the number ; in short, for the ama-touched the optic tubercles the results teurs of analog-y, even the phalanges becomewould have been far different. so many vertebrae ; all this is fine andlearu-

Let us now pass to the sense of hearing, ed enough, but for my part I prefer a goodand study the connection between the phy- experiment.siological and pathological phenomena Leaving, then, the analogy between thewhich present themselves here. You are, eye and ear to those who have a taste fordoubtless, suuicietitly acquainted with the such matters, I tell you that the acousticanatomical disposition of the human ear, a nerve arises by a set of fine white filamentspoint which I may dispense myself from en- along the floor of the fourth ventricle, attering on with any degree of minuteness, that part which anatomists call calamusthe more readily that we know but very scriptorius. On separating from the brain itlittle indeed on the uses. of the various is closely applied upon the facial nerve,parts which enter into the composition of and having entered an opening in the petrousthe internal ear. _ portion of the temporal bone, it divides intoThe auditory apparatus is a very compli- several branches, which are distributed to

cated one; and, like the eye, is composed the semicircular canals, and to the cochlea.of a number of parts, which seem well cal- The mere anatomical disposition of theculated, from their physical properties, to nerve is sufficient to make us conclude thatperfect the function they are subordinate it is intimately connected with the functionsto; these parts communicate, on the one of hearing; but, as we said before, thehand, with the external world, through the middle ear and the internal ear are also tra-medium of the atmosphere, and on the other versed by other nervous branches, whosewith a peculiar nerve, destined to receive presence, in all probability, influences moreand transmit certain impressions to the sen- or less the exercise of the function nowsorium. Anatomists distinguish four priti- under consideration. Of these nerves thecipal parts in the auditory apparatus, viz., principal is the facial nerve, which youthe external ear, the middle ear, or vesti- know traverses a peculiar canal in the tem-bule, the internal ear, or labyrinth, and, poral bone, from the internal auditory fora-finally, the acoustic nerve (portio mollis) of men, where it enters, to the splenoid-mastoidthe eighth pair. foramen, which gives it exit. As to theThe researches of natural philosophers connexion between the facial and auditory

have as yet thrown but little light on the nerves, I do not think that any anastomosislaws which govern the formation and trans- between them has been demonstrated, normission of sounds; indeed, we may say the have I ever myself observed any trace ofscience of acoustics is at present completely such connexion ; and here I would beg youin its infancy; for my own part, I have to remember the difference between juxta-been unable to apply physics to the study position and true anastomosis of nervousof the physiology of the human ear ; at- substance. As to the vidian nerve, the re-tempts have been made I know, but the searches of M. RIBES show that it has noresults are unfortunately of a very insignifi- immediate connexion with the nerve ofcant nature.

. hearing; however, the more modern dissec-Unable to follow up or explain the me- tions of ARNOLD, confirmed by some of our

chanical part of the organ of hearing, the own anatomists, fully establish a communi-physiologist turns to that portion which is cation between the fifth and auditory nerves.more immediately connected with the centre As to the anastomoses which exist in theof the nervous system, and which, under cavity of the tympanum, between the seve-the name of auditory nerve, is supposed to ral nerves there found, these are well esta-transmit into the brain the impressions it blished at the present day, and known toreceives from without. But the auditory eyery one.nerve is not the only one contained in the The brief auatomicalconsiderAtious whichinternal ear; anatomists have described I have just laid before you, are, as you mustseveral others, and hence have sought for be convinced, totally insufficient to furnishanalogies, more or less fancifully worked any grounds for determining how far the

up, between the organs of hearing and see- portio mollis, or acoustic nerve, influencesing. The greater part of these are mere the sense of hearing. Our experimentsaberrations of the imagination ; vain and have demonstrated that the optic nerve isuseless efforts at discovering analogies, actually the nerve of vision, for the func-which, generally speaking, are nothing tion cannot exist without the nerve; but, atmore than forced similitudes, that a strict the same time, they showed us how theand philosophical observer cannot admit, olfactory nerves are far from having theThe fact is, that analogy is the fashionable same connexion with the organ of smell.hobby of the day. Look at the vertebra? ! Now, it is by no means improbable, that the

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same may occur with respect to the organ ofhearing ; the connexion which modern ana-tomists have shown to exist between theacoustic nerve and the fifth indicates sufli-

ciently the nature of the influence whichthe one may exercise over the other. I donot, however, remember any experimentsmade with the view of clearing up thispoint ; nor have I ever made any myself;but something must be done. We shall pre-sently see, or, at least, we will endeavourto see, if animals become deaf when theacoustic nerves are divided within theskull; but I should warn you that it is ex-tremely difficult to appreciate the results ofexperiments made on the organ of hearing inanimals; thus, they may hear the noise wemake distinctly enough, without giving anysign of sensibility. In addition to this, youknow how the organ is surrounded on allsides by extremely hard parts; in the centreof one of the hardest bones of the body ;nnatiy, it may be the same with the sense ofhearing as with that of smelling; the gene-ral sensibility may play a more importantpart than the special sensibility in the pro-duction of the former sense, as we haveshown that it does in the latter. Vibra-tions are communicated by the sense oftouch, and the same phenomena producedas if a person heard, even when the hearingis completely lost.

In herbivorous animals, the rodentia, &c.,the sense of hearing is destroyed by a sec-tion of the lifth pair of nerves, but when weperform the same experiment on dogs, wedo not constantly obtain the same effects.The influence which the fifth pair exercisesover the functions of the organ of hearing isvery remarkable, when we consider it in

relation to anatomy. Thus, when experi-menting on the organ of hearing, we cut thefifth pair at a point more or less distant

from where it sends off its anastomosingfilaments to the acoustic nerve; while, onthe contrary, for the senses of smelling andseeing the fifth is divided, after it has sent

off its branches of communication to those

organs. It would be curious to investigatethe’nature of this difference, but as yet wehave made no experiments with this view.As to general insensibility, the acousticnerve ranks with the optic and olfactory ;you may irritate it to any degree withoutproducing the least disagreeable sensation;you may even lacerate it without makingthe animal cry : hent e the auditory nervepossesses only special sensibility. Thesense which now occupies our attention,will require a great number of experiments,we shall, therefore, defer any further c,)ii-siderations to our next meeting.

CLINICAL

LECTURES AND REMARKS,DELIVERED ON

DISEASES OF THE SKIN, VENEREALDISEASES, AND

SURGICAL CASES,AT THE

SKIN INFIRMARY, AND AT THE JERVIS-STREET HOSPITAL, DUBLIN.

BY DR. WALLACE,SURGEON TO THOSE INSTITUTIONS.

The consideration of the EXANTHEMATIC FORMSOF SYPHILIS, continued. Case of M. D., thewife of P. D. Reports of her case during itsfirst period, or to the thirty-fifth day afterher application, bei2t,-- azz account of the up-pearazzces on her genital organs.—REMARKS.The correspondence between the character ofher disease, and that of her husband. Origin,development, and ncctune, of the symptomscalled condyloma. State of the sebaceousducts of the cutis affected by this symptom.Influence qf this disease on the state of thecuticle and cutis. Consiclerutiort of thequestion, whether the appeurunces on the

genital organs were primary or constitu-tional. Differences between primary andconstitutional condyloma. Effect of inoctt-lation with her 0!fM matter, Conclusionfrom the experiment. Effect of inoculationwith the iiiatter of P. D. after she had pre-sented constitutional symptoms. Conclusion,and enunciation of some important lawswhich govern the propagation of the venerealpoison.GENTLEMEN:—In my last lecture on Sy-

philis, (LANCET, May 20, page 282), I readto you the reports of the case of P. D., andmade upon it some remarks. There are

still, however, several facts relative to thatcase upon which I have yet to animadvert;but I shall for the present postpone them,as they will find a more natural place whenI come to consider the corresponding factspresented by the

Case of M. D., the wife of P. D.The case of this woman extends through

so long a period, and the symptoms havebeen registered so circumstantially, and withso much accuracy, that the details would,perhaps, be tiresome if uninterruptedly re-lated. It will, therefore, be the better planto divide the whole period occupied by theprogress of this case into minor periods, andto make, under distinct heads, such generalremarks as may be prompted by the factswhich each period affords. I shall includein the first period the history of the case to