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to lumbago. On the contrary, he had stated that the two-were commonly combined, the lumbago often preceding the=sciatica, but he had endeavoured to show that where this wasnot the case, when the pain commenced in the hip or sciaticllerve, the presence of a tumour within the pelvis might besuspected, and a careful examination should be made

accordingly. He was sorry to observe that Dr. Lankesterhad left the meeting, as he considered that when a gentleman.charges another with having offered opinions which he cannot,support, and with having jumped at conclusions, he shouldawait the reply. After such observations he was certainlysurprised at the assertions of Dr. Lankester, that he had givenno proof of the correctness of his theory, that there was noproof of sciatica depending upon the accumulation of fasces, orof the benefit of his (Mr. Hancock’s) treatment, excepting themere removal of feculent matter, and the relief affordedthereby. Now, he (Mr. Hancock) considered this as very,conclusive support of the opinions he had offered, and hecould not imagine that the Society would think he hadjumped to a conclusion in arriving at such a, deduction. Dr..Lankester laid great stress upon his (Mr. Hancock) having- -employed quinine in large doses in the treatment,. andendeavoured to deduce from this fact that after all it was thequinine which effected the cure, but not the evacuation of the’contents of the alimentary canal, that it was merely a questionas to whether the exhibition of quinine should be preceded byaperients or not. He (Mr. Hancock) could not regard the.question in that light. He had administered the quinine with- the especial desire of removing the morbid irritability set upin the nerve. He had never denied the existence of the irri-

tability in the nerve, neither would he deny that there mightalso be congestion of the neurilemma of the nerve; but what hewould deny was, that either this morbid irritability, or this.congestion, or effusion of fluid within the neurilemma, if suchdoes at any time exist, are the causes of the disease; but, onthe contrary, he would maintain, that they are resultsdepending upon other causes, and that whilst he would notpresume to deny that the sciatic nerve could by any possibilitybe the seat of inflammation of a rheumatic character, he wouldurge that such are exceptional cases, and that by far thelargest majority depend upon the causes he had assigned inhis paper. It is not extraordinary when a nerve has beenirritated for months, or even years, that although the excitingcause of such irritation be removed, a certain degree of morbidsensibility should remain, and this is shown by the sensationof bruising which remains after the scybalas have been ejected:it was to get rid of this sensation that he gave the quinine.which would be of no avail if the exciting cause were nopreviously got rid of. He had not confined himself to case;. arising from impacted fæces, as stated by Dr. O’Connor; on th(contrary, all those which he had narrated had been previouslyconsidered rheumatic, and treated accordingly, without thl

slightest benefit. In conclusion, he would again allude to thlfact, which he does not believe is recorded elsewhere, that a;a general rule sciatica attacks the right sciatic nerve, ver

. rarely the left. He begged to thank the fellows for thepatience with which they had heard him.

PHYSIOLOGICAL SOCIETY.

MONDAY, FEB. 13, 1854.—MR. RICHARDSON in the Chair.

Mr. PiLCHER commenced by stating that his object in relatingthe subject,A FEW POINTS CONNECTED WITH THE PHYSIOLOGY OF THE

TYMPANUM,for the evening’s discussion v.’as to elicit the opinions of thefellows of the Society in reference to certain conditionsand functionss till debateable and debated. He avoided allreference to the external ear, and likewise to the labyrinth,confining his observations as strictly as perspicuity wouldadmit to the mode of action and influence of the middle ear, ortympanum. He noticed that in the very threshold of theinquiry we cannot but be struck with the interesting fact ofthe existence and purpose of the tympanum being confined tothe modification of and influence upon aerial sounds, and that,though found in aquatic mammalians and reptiles, and amphi-bians, its structure in those creatures is so modified for its pro-

tection and occlusion when in the water, as then most

probably to be closed from all action and function, so as tojustify the physiologist in his conclusion that a tympanum,including its appendages, is in its functions peculiar to air-

breathing, and consequently air-hearing animals, and that it isin direct association with the medium conveying sound. Yetit is also recognised that the tympanum becomes importantlymodified in the different orders of terrestrial beings in corre-spondence with the development of the brain, and consequentlyof the intelligence ; thus its complexity and perfection aregradually advanced through the orders of animals till it reachesits supposed perfection in man. We are thus led to the con-clusion that the great end and intention of the tympanum isso to extend and multiply the modifications and variations ofsound as to give rise to that infinite variety of impressionsupon the mind which constitutes articulate language. It is noargument to the contrary that the passores are capable ofwarbling a language readily comprehended by their mates, and.delighting the world around, with a tympanum no moreelaborately organized than the amphibian or the higher reptile.The great differences in the capacity of voice and its apprecia-tion are due to corresponding differences in the peculiarities ofmental development, suiting each class of being to its especialuses and habits. The same objection (if urged at all) mightbe more forcibly urged upon the comparison of the range ofvoice and hearing in the nightingale and the rook, the anatomy

, of whose organs both of hearing and voice are exactly the, same. Nor is it a sufficient argument to the contrary of the

above proposition, that the recognition of articulate languageis but little impaired in many instances by the loss (even itmay be complete) of the entire structure as an organ ofaudition. He (Mr. Pilcher) had frequently seen the generallaw,-that loss of function is in direct ratio to the change orloss of structure,-reversed in the case of the tympanum, andthat a slight hypertrophy of the membrane had occasioned aserious amount of deafness; and, on the other hand, the com-plete loss of membranes and ossicles, including even the stapes,

to be unattended with ordinarily appreciable diminution ofhearing. Who would argue from these facts that the tympanumis of little importance or useless in the economy of audition ? ’!Yet they prove, among other conditions, that it is simply anappendage to more important structures, and that the loss ofits function can be supplied by an exaltation in the function ofthe essential portion of the organ-the nerve, in its course andexpansion,-aided by the increased power of the mental per-ceptions. Mr. Pilcher here stated his utmost conviction thatif this principle were applied to cases of the deaf-dumb, arisingfrom malformation of the labyrinth, (which malformation isgenerally a partial deficiency of development,) many unfor-tunate cases would experience such an amount of improvementas to become so capable of the enjoyment of hearing as toensure its necessary accompaniment, speech. In reference to*the membrana tympani, Mr. Pilcher stated that it was not a pureconcavo-convexity ; described its divisions into three surfaces,and noticed that the manubrium of the malleus, usually passingbackwards, sometimes runs forwards, and sometimes does notreach the centre ; circumstances pointing to the fact that

though the obliquity of the membrane and of the bone is im-portant, the precise direction of that obliquity is unimportant.He has occasionally seen the upper part of the superior pos-terior division of the membrane more diaphonous than the rest,the margins being semilunar and well defined, as though thetrue membrane were there deficient, and which he expectsconstitutes the membrana iiaceida of Sharpnell, and which hebelieves to be a congenital deficiency in the membrane, and, asin most malformations, is an approach to the the normal con-dition in some lower animals ; many mammalia, and perhapseven all, have a large regular oval aperture in the upper andback part of the membrane, just behind the neck and superiorpart of the handle of the malleus, through which there exists a,free communication with the interior of the cavity of thetympanum. Allusion was made to Mr. Toynbee’s views -ofthe structure of the membrane, and though it was undoubtedthat both fibrous layers were in continuation with the periosteumat the ring of bone in which the membiane is set, yet thatcontinuity does not constitute identity, and that Mr. Blenkins,from very careful microscopic investigations, declares that thismembrane is very unlike the common fibrous tissue of. thebody. As the external fibrous layer of the membrane con-verges from every part of the circumference, expect the upper,where the bone is deficient, to be attached to the entire extentof the manubrium of the malleus, it follows, Mr. Pilcher states,of necessity, that each fibre must differ in length from all theothers, and likewise in its curve, and it is possible also in itsdensity and in its tenseness. The internal layer of Sbrea isless uniformly spread over the membrane, circular, and moreabundant at the circumference. After some further observa-tions upon the anatomy of the membrane, Mr. Pilcher called

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attention to a few obvious facts as connected with the vibra-tions of membranes, of which that of the tympanum offers agood example :-lst, That a membrane vibrates rapidly in pro-portion to its tensity; however, according to the experimentsof Savart, Willis, Wheatstone, and others, there appears to bea limit to the vibratibility of a membrane, that it may berendered so very tense as to be incapable of further motion,even vibration. 2nd, That it vibrates rapidly in proportionto its thinness, the condensation of its material, or its tenuity, Ior resistance. 3rd, That the entire membrane does not neces- i

sarily vibrate at the same time; that one portion may be in a ’,state of rest while others are actively moving. 4th, That inall instances when the whole extent is said to be in agitation, ’,it is vibrating in lines with intervening spaces at rest, and thatthese lines will be determined by their density and tension,the interstices at rest being the nodal points. ath, That theselines themselves must necessarily vary in their capability tovibrate, as they differ in length, in tenseness, in solidity, ordensity; in fact, though so arranged together as to constitutea membrane, each line or fibre is moving in obedience to thesame laws which regulate a vibrating musical chord - a

vibrating membrane being but a series of vibrating chords.6th, That a line or chord, whether constituting a part of amembrane or stretched out alone, as a string, may vibratethroughout its entire length or in separate and distinct por-tions, and either at the same time or at different intervals,when vibrating in different portions or lengths, the interveningspaces form the nodal points. 7th, That exactly in reverseproportion to the rapidity of vibration will be the extent towhich the fibres will move in the surrounding medium. 8th,And that thus the highest or most acute note proceeds from astring or chord at the same time most dense, most tense,smallest, shortest, and vibrating through or in the mostlimited space; a chord vibrating under the reverse of theseconditions will produce the lowest or deepest note or sound.Upon applying these principles, and from the experiments ofSavart and others it is found that the healthy membranatympani fulfils all these indications, and that it is capable ofvibrating from 16 to 24,000 times in a second of time ; that anote so low as to occupy the sixteenth part of a second in thevibration of the membrane can be appreciated in the humanmind ; and another so acute that the vibration of the mem-brane occupies only the twenty-four-thousandth part of asecond can be perceived. In considering this subject whilepreparing the essay upon the ’’ Economy and Diseases of theEar," to which the Council awarded the Fothergillian medal,Mr. Pilcher was led to conclude that, as the fibres of the mem-brane certainly differ in length, and probably in density andthickness, and are regulated as to their tensity by muscularaction, so each fibre, delicate as it is, possesses its own specialdegree of vibratibility, and that therefore though many or allmay vibrate at the same instant and from the same cause, eachwill vibrate with its own intensity or to its own special extent;and that thus it is possible, nay probable, that in the humanmembrana tympani there is a chord capable of vibrating inconcert with every sound known to the human mind: a sym-pathetic chord producing a sympathetic note, in unison with acorresponding note, though issuing from a different instrument,and which note the musical world so well knows passes overevery string not in unison with it till it meets with that in itssympathy, and in which it excites a corresponding musicalsound. Mr. Pilcher recited several facts in proof of thisdoctrine, which appears to him capable of explaining manyphenomena otherwise inexplicable; among others, the circum-stance of some persons, with otherwise healthy organs, beingdeaf to certain sounds hearing others perfectly well; the readyrecognition, in a concert, of the various instruments of diffe-rent pitch and quality, though playing the same music, &c. &c.The ossicula were described as so arranged and articulated asto form an active and powerful spring, its movable extremitybeing the malleus attached to the freely vibrating membranatympani, and its more fixed end being the stapes secured tothe membrane of the fenestra ovalis, it must therefore first actfrom without inwards, springing back to its condition of restwhen the operating cause is removed; besides which the oscil-lations backwards and forwards must be very considerable andrapid, and increased in proportion to the leverage formed bythe processes of the bones and their articulations. Thus, then,the vibrations of the comparatively large membrana tympani,or so much of it as may be in action, are importantly augmentedas well as modified in their transmission through the osseouschain, and become concentrated upon the comparatively smallmembrana fenestræ ovalis. But, furthermore, these little bonesmodify and regulate the action of the tympanic membrane

itself through the medium of the muscular action with whichthey are endued. Mr. Pilcher does not speak certainly ofmore than two muscles attached to and working these interest-ing bones. The tensor tympani is so arranged as to powerfullydraw the malleus inwards, thus tightening the membrane,increasing its vibratibility, shortening and compressing theosseous spring, and forcing the membrane of the oval openinginwards upon the vestibule. Most likely the great power ofthe muscle is also to turn the membrane to a degree beyond thevibratile capacity. Is it possible that the spasmodic and violentcontraction of the muscle upon the sudden and unexpectedapplication of a loud sound, may be so great as to rupture themembrane ? Mr. Pilcher knows from experience that suchruptures do occur. The stapedius must force the stapes in-wards, compressing the fluid of the labyrinth; and in so doingmust also still further draw the membrana tympani inwards,and also roll the stapes upon its axis; and probably it possessesa more important influence upon the undulations of the aquathan we suspect. These muscles, deriving their nervous supplyfrom various sources, and largely from the excito-motorysystem by means of the otic ganglion, are of the mixed cha-racter, both voluntary and involuntary, by which means weare enabled at will to tighten the membrane to concert pitchwith sounds we desire to clearly perceive, and to permit itsrelaxation by discontinuing the volition, and as they are in anespecial manner supplied from the excito-motory system, it isfair to conclude that there exists a corresponding especialaction, which involuntary action is called into full operationby the excitement of a loud, discordant, or otherwise dangeroussound. In these actions we recognise a close resemblance, asArnold has so well remarked, with the functions of the iris,the involuntary controller of the quantity of light to be ad-mitted to the eye. In considering the tympanum as.an atmo-spheric chamber, with diverticula for enlargement, Mr.Pilcher regards its chief use to suspend the membrane andossicles in a medium exactly and ever alike, both within andwithout; and as confined air is known to undergo changes inits elasticity, density, and other qualities, more than can beaccounted for by rarefaction alone, so does it require to be con-stantly renewed, for which purpose the Eustachian tube is

appended. Sir Charles Bell’s view was adopted, that in ahealthy organ all the vibrations of the membrane, modified andincreased in power, are transmitted along the ossicula, andconcentrated upon the membrane of the oval fenestra, themovements of which produce undulations in the aqua, whichrunning round the various windings of the labyrinth, impingeupon the inner surface of the membrane of the round opening,which yielding correspondingly, projects outwards towards thetympanic cavity, it is again restored, partly by its own elas-ticity, partly by the reaction of the air, it is true that theopposite opinion of the tympanic atmosphere alone exciting thevibrations of the membrane of the fenestra rotunda, and so in-fluencing the water in the scala tympani, would more readilythan can now be done account for the use of the cupola, theundulations of the water of both scala thus meeting, wouldform a nodal point, and neutralizing each other, become atrest; but that doctrine would render it necessary to supposethat the labyrinth was not filled with fluid, but was partlyoccupied with a compressible gas or air, for which theory thereis insufficient data. Mr. Pilcher is unable to consent to theview that the tympanum is a necessarily closed cavity, airbeing admitted only occasionally, upon deglutition, throughthe Eustachian tube, adopted by Mr. Brooke, Mr. WhartonJones, and lately more particularly insisted upon by Mr.Toynbee, for the following, among other reasons :-lst, It iscertainly not requisite that the tympanum be a closed chamber;we see apertures through the membrane, arising from accident,without other lesion, not producing the slightest deafness.2nd, In many mammalia, and perhaps in all, an aperture inthe upper part of the membrane normally exists. 3rd, Theair in many cases constantly flows outwards from the tym-panum through an aperture, being one cause of tinnitus, fromthe vibrations of the lips of the opening, which necessitates itscontinued entrance by the Eustachian tube. 4th, In his ex-perience, the more complete closure of an aperture in theulcerated membrane by means of Mr. Toynbee’s artificial mem-brane, has not been attended with such useful results as theincomplete closure by the wetted cotton. 5th, The unpleasant,sometimes painful, sensation upon every inspiration, withoutdeglutition, when a resisting piece of hardened wax laysagainst the membrane, evidently occasioned by preventing itsslight movements, and the instant relief upon the removal ofthe foreign body. 6th, The fact that when the Eustachiantube is closed by contraction or by the pressure of an enlarged

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tonsil-both conditions of very rare occurrence-deafness is theresult, and removable by re - opening the tube. 7th, Inclosure of the tube from extensive ulceration of the fauces,producing deafness, the sense was in a fair degree restoredwhile the catheter remained in the tube. 8th, The case of achild - William Lee — being instantly restored from deaf-dumbness of four years’ duration, upon the removal ofinspissated mucus from the tube by means of catheterism, thechild receiving no further treatment than subsequent educa-tion. 9th, In cases of mucous accumulation in the cavity, theimmediate and very complete restoration from extreme deaf-ness, often temporary, but sometimes permanent, uponcatheterism, which can hardly be solely attributed to the re-moval of the mucus. 10th, That the same " sensation of ful-ness and pressure is experienced in the tympanic cavity" bypressing the finger into the outer meatus, as is produced by anact of deglutition, and in both instances in consequence of thecondensation of air upon the membrane, though upon theopposite surfaces. llth, That it is of necessity that the effortof deglutition, the month and nose being closed, must condensethe air in the cavity through the patent tube. 12th, That amore remarkable condensation takes place, sometimes even torupture the membrane, in consequence of a forced expiration,without any probable action of the muscles, as is not in-

frequently seen in cases of hooping-cough or other spasmodicexpiration. 13th, The attachments of the two muscles, thelevator palati and circumflexus palati, to the Eustachian tube,seems rather destined to close than to open the tube, though itis most probable they exert no direct action upon the tube, butan indirect one in closing it. 14th, In birds, the arrangementof these tubes is peculiar, for the purpose of allowing them tcrespire freely, and to catch and swallow their food whilst inrapid flight; and in many mammalia, and particularly in

aquatic reptiles, the structure is peculiarly modified for adaptation to especial habits. 15th, The generally-received opiniorthat all the openings, including those of the Eustachian tubesinto the pharynx, are usually patent, becoming close duringthe act of swallowing, by the expansion and elevation of th,soft palate, is more in accordance with the acknowledged process of deglutition. And, 16th, Were it otherwise, the tubewould be opened only at a moment the most inconvenient fothe admission of air, when they were closed towards threspiratory organs, and must be with difficulty supplied throug:the nares.

Dr. CRisp agreed with the author as to the value of the tympanum, and observed that in Turkey and other Easterncountries it is the custom to perforate the tympanum in orderto permit tobacco-smoke to pass from the throat out of theears. He considered this a sufficient proof that such inter-ference with that membrane did not produce any degree ofdeafness, otherwise the practice would not have been adopted.He had moreover, in the course of a careful dissection of anAlbina cat, been quite unable to detect any difference of struc-ture, although these animals are probably always deaf. Hewished to inquire whether the dog and pig have a perforatetympanum, as they at all events can readily appreciate sound.

Mr. RICHARDSON made some remarks upon a coincidencewhich he had observed between the occurrence of the arcussenilus and deafness, the arcus senilus being observable in agedpersons, who were at the same time deaf, whilst absent inothers whose hearing was perfect.Mr. DAVIS, on the contrary, objected that although the

arcus was visible in his own case, he was yet quite free fromdeafness, and that the same thing had occurred in his father,who died at the age of eighty-four, in perfect possession of thEfaculty of hearing.

Dr. GIBB propounded a query as to whether the membranewere ever ruptured in hooping-cough.Mr. TOYNBEE objected to the author’s statement in regard

to the non-closure of the Eustachian tube, the functions of theossicles, and the precise value of the membrana tympani. Hewas in a position again to assert that the Eustachian is reallya closed tube, and this opinion he had recently been enabled tocorroborate by the investigation of the part in the loweranimals, both mammals and birds. In no instance was anymechanism discoverable designed for preserving its patency,whilst, on the other hand, there were always two muscles scarranged as to open the tube when circumstances should rendeiit desirable. He denied that the ossicles were designed for thEconveyance of vibrations of the fenestra ovalis, since they werEby their arrangement unfitted for such an office ; and with theexception of the stapes, they might be dispensed with withoua necessary loss of hearing. In the bird, moreover, the bomis attached to the membrane by ligament, and not by bone

The presence of the stapes, however, he considered essential tothe faculty of hearing. He considered that the connexion ofdeafness with closure of Eustachian tube was occasioned by thefact that where the latter occurs, the membrane is allowed tofall in, and thus press upon the fluid in the labyrinth. Hebelieved that any lesion or imperfection of the membrane wasincompatible with perfect hearing.

Mr. BISHOP opposed the author upon several points. Hebelieved that the movements of the discs were governed by thesame laws as regulated the vibrations of cords -that theyvibrated as a whole-consequently, he could not admit thatthe fibres of the tympanum could act individually, and thewhole as a number of separate cords. After touching uponthe recent discoveries of a French mathematician, he remarkedthat the author of the paper which had just been read seemedto have overlooked the important characteristic of the elas-

ticity of the membrane.Mr. PILCHER stated in reply that he had himself remarked

the existence of a dark line around the tympanum in old sub-jects, but had not connected this appearance with the arcussenilis. In hooping-cough there were frequent examples of

, rupture of the membrane, but the mischief was usually soonrepaired. The fact that a patient could only hear well by

, opening his mouth, he accounted for by supposing that this hadthe effect of expanding the external meatus, and admitting air

more freely. The whale and other cetaceous animals hear, through the Eustachian tube, which opens into the blow-hole,band is the only part above water; but in these animals theb ossicles are unconnected with the tympanum. From an ex-tamination of Mr. Toynbee’s preparation of the tympanum of)the bird, he believed that the bone was directly attached toa that membrane.

ROYAL MEDICAL AND CHIRURGICAL SOCIETY.

THE annual general meeting of the Society, for the electionof officers, &c., was held on Wednesday, Dr. Copland in thechair. After the usual ordinary business, which consistedchiefiy of the reports of the auditors and the council, whichshowed that the Society was in a prosperous condition, thefollowing gentlemen were elected office bearers for the ensuingyear :-President: James Copland, M.D., F.R.S.—Vice-PresidentsThomas Alfred Barker, M.D.; Robert Bentley Todd, M.D.,

F.R.S.; Thomas Bell, F.R.S.; Thomas Wormald.—Treasurers:Joseph Moore, M.D.; Thomas Blizard Curling, F.R.S.—Secre-

taries : WN illiam R. Basham, M.D.; Holmes Coote.—Libra-rians: William Wegg, M.D.; James Dixon.-Other Members

of Council: George Chaplain Child, M.D.; William Dingle, Chowne, M.D.; Mervyn A. N. Crawford, M.D.; Henry S.

Dyer, M.D.; Thomas H. Silvester, M.D.; John Avery;William Harvey; Henry D. Jones; John Simon, F.R.S.;

, Henry Spencer Smith.

PETITIONS TO THE HOUSE OF COMMONS.

To the Honourable the House of Commons of the Parliament ofGreat Britain.

The Humble Petition of James Baker, of No. 1, Dor-chester-place, New North-road, Hoxton, in the Countyof Middlesex, Chairman of the Hoxton Medical Pro-tection, on behalf of himself and the Members of thesaid Society,

Showeth-That your Petitioners have carefully read the Billnow before Parliament for the Registration of Qualified MedicalPractitioners.That your Petitioners are deeply interested in protecting

the lives of her Majesty’s subjects and maintaining the re-’ spectability of that honourable profession of which they aremembers.

That your Petitioners are of opinion that the said Bill is a) wise and judicious measure; and that if passed into a law willr prove a benefit to society by enabling her Majesty’s subjectsT readily to distinguish between persons practising Medicine and, Surgery by virtue of lawful authority, and those who do notpossess any legal qualification whatever.r That your Petitioners are convinced, that for the due pro-e tection of the public, as well as for upholding the dignity ofe the Profession and securing the just rights of medical men, ae clear and certain remedy should be provided..t Your Petitioners therefore humbly crave leave to ask youre Honourable House to give effect to the measure now intro-3. duced for the Registration ûf Qualified Medical Practitioners,