From this Region of the Tympanum, I might

pafs

For this Opinion of Dr. Willis, Dr. Schelhammer is very severe upon him, deriding the Refractions he fpeaks of; and therefore feriously proves that they are the Humours, not Tunicks of the Eye, that refract the Rays of Light; and then jeeringly demandeth, whether the fonorous Rays are refracted by paffing through a different Medium? Whether the Convexity or Concavity of the Drum collects thofe Rays into a focal Point, or fcatters them, &c. And then faith, Ob has rationes à clariff. Viri, ac de re Medicâ præclarè meriti, fententiâ non poffumus non effe alieniores: in quo uti ingenium admiror, quoties medicamentorum vires, aut morborum caufas explicat, fic ubi forum fuum egreffus, Philofophum agit, ac vel Partium ufum, vel Chymicarum rerum naturam fcrutetur, ejus haud femel non modò judicium defidero, verùm aliquando etiam fidem. This is so fevere and unjust a Cenfure of our truly famous Countryman, (a Man of known Probity) that might deferve a better Answer; but I have only Time to fay, that although Dr. Schelhammer hath out-done all that wrote before him, in his Book de Auditu, and fhewed himself a Man of Learning and Industry; yet as our Countryman wrote more than he, (though perhaps not free from Errors too) fo he hath manifested himfelf to have been as curious and fagacious an Anatomist, as great a Philofopher, and as learned and skilful a Physician, as any of his Cenfurers, and his Reputation for Veracity and Integrity, was no lefs than any of theirs too. But after all this terrible Clamour, Dr. Schelhammer prejudicately miftaketh Dr. Willis's Meaning, to fay no worse. For by utraque Membranæ refringunt, Dr. Willis plainly enough, I think, means no more than a Restriction of the Ingrefs of too many Rays; as his following explicatory Words manifeft, viz. refrin gunt, & quafi emolliunt, eafque Senforio non nifi proportionatas tradunt. But indeed Dr. Schelhammer hath fhewn himself a too rigid Cenfor, by making Dr. Willis fay, the Ear-Drum hath fuch like Braces as the War-Drum, viz. Quod porrò de machinis feu taniis Tympani bellici adducit, dicitque idem in Tympa no auditorio confpici, id prorfus falfiffimum eft. I wonder Dr. Schelhammer did not alfo charge Dr. Willis with making it a Porter, fince he hath in the fame Paragraph, Janitoris officio, &c. But Dr. Willis's Meaning is plain enough, that the little Bones and Mufcles of the Ear-Drum do the fame Office in ftraining and relaxing it, as the Braces of the War Drum do in that. And confidering how curious and folemn an Apparatus there is of Bones, Mufcles, and Joynts, all adapted to a ready Motion, I am clearly of Dr. Willis's Opinion, that one great

Ufe

Ufe of the Ear-Drum is for the proportioning Sounds, and that by its Extenfion and Retraction, it corresponds to all Sounds, loud or languid, as the Pupil of the Eye doth to feve ral Degrees of Light: And that they are no other than fecondary Ufes affign'd by Dr. Schelhammer, as the principal or fole Uses of keeping out the external colder Air, Duft, and other Annoyances; but especially that, Ob folius aeris interni potiffimùm irrumpentis vim, hunc motum Tympani ac Mallei effe conditum, ut cedere primùm, deinde fibi reftitui queat; as his Words are. P. ult. C. 6. Sect. 13.

It was no improbable Thought of Robault, Nos attentos præbere, nil aliud eft, nifi Tympanum, ubi ita opus eft facto, contendere aut laxare, & operam dare ut illud in eâ pofitione intentum flet, in qua tremulum aeris externi motum commodiffimè excipere poffit. Roh. Phyf. p. 1. c. 26. fect. 48.

The Hearing of deaf Perfons more eafily by Means of loud Noifes, is another Argument of the Ufe of the Straining or Relaxation of the Tympanum in Hearing. Thus Dr. Willis (ubri fupra) Accepi olim à viro fide digno, fe mulierem novisse, quæ licèt furda fuerit, quoufque tamen intra conclave Tympanum pulfaretur, verba quævis clarè audiebat: `quare Maritus ejus Tympaniftam pro fervo domeftico conducebat, ut illius ope, colloquia interdum cum Uxore fuâ haberet. Etiam de alio Surdaftro mihi narratum eft, qui prope Campanile degens, quoties unà plures Campana refonarent, vocem quamvis facilè audire, & non aliàs, pa

tuit.

Abfciffo Mufculo [Proceffus majoris Mallei] in recenti aure, relaxatur [Tympani Membrana.] Valfalv. de Aur. Hum. c. 2. fect. 5.

Upon confidering the great Difference in Authors Opinions, about the Ufe of the Parts, and Manner how Hearing is performed, as also what a curious Provifion there is made in the Ear, by the four little Bones, the Muscles, Membranes, &c. I was minded (fince I penned this Note) to make Enquiry myself into this Part, and not to rely upon Authority. And after a diligent Search of various Subjects, I find we may give as rational and eafy an Account of Hearing, as of Seeing, or any other Sense; as I have fhewn in my last cited Note (d), Book VII. Chap. 2. with Relation to Birds. And as to Men and Beafts, the Cafe is the fame, but the Apparatus more complex and magnificent. For whereas in Birds, the auditory Nerve is affected by the Impreffions made on the Membrane, by only the Intermediacy of the Collumella; in Man, it is done by the Intervention of the four little Bones, with the Muscles acting upon them; his Hearing being to be adjusted to all Kinds of Sounds, or Impreffions made upon the Membrana Tympani. Which Impreffions are imparted to the auditory Nerve, in this Manner, viz. Firft they act upon the Membrane and Malleus, the Malleus upon the Incus, and the

pass to that of the Labyrinth (w), and therein furvey the curious and admirable Structure of the Veftibulum, the Semicircular Canals (x), and Cochlea; particularly the artificial Gyrations, and other fingular Curiofities observable in the two latter.

But I fhall not expatiate on these reclufe Parts; only there is one fpecial Contrivance of the Nerves miniftring to this Senfe of Hearing, which must

not

Incus upon the Os Orbiculare and Stapes; and the Stapes upon the auditory Nerve: For the Bafe of the Stapes (the fame as the Operculum in Birds) not only covers the Feneftra Ovalis, within which the auditory Nerve lieth, but hath a Part of the auditory Nerve fpread upon it too. It is manifeft that this is the true Process of Hearing; because if the Membrane be mov'd, you may fee all the Bones move at the fame Time, and work the Bafe of the Stapes up and down in the Feneftra Ovalis, as I fhewed in this Chapter, Note (d), concerning the Mole; and as it may be seen in other Ears carefully opened, if the Parts remain in fitu.

(w) I do not confine the Labyrinth to the Canales Semicirculares, or any other Part, as the elder Anatomists seem to have done, who by their erroneous and blind Descriptions feem not well to have understood thefe Parts; but with those much more curious and accurate Anatomifts, Monfieur de Vernay, and Dr. Valfalva; under the Labyrinth I comprehend the Canales Semicirculares, and the Cochlea, together with the intermediate Cavity, called by them the Veftibulum.

(x) In the femicircular Canals, two Things deferve to be noted. 1. That the three Canals are of three different Sizes, Major, Minor, and Minimus. 2. Although in different Subjects, they are frequently different; yet in the fame Subject they are constantly the fame. The Reafon of all which, together with the Ufes, Valfalva ingenioufly thinks is, that as a Part of the tender auditory Nerve is lodged in thefe Canals, fo they are of three Sizes, the better to fuit all the Variety of Tones; fome of the Canals fuiting fome, and others, other Tones. And although there be fome Difference as to the Length and Size of thefe Canals, in different Perfons; yet, left there fhould be any Difcord in the auditory Organs of one and the fame Man, thofe Canals are always in exact Conformity to one another in one and the fame Man. V. Valfal. ubi fupr. Ch. 3. Sec. 7. and Ch. 6. Sect. 4, 9.

Book IV. not be paffed by; and that is, the Branches of one of the auditory Nerves (y), fpread partly to the Mufcles of the Ear, partly to the Eye, partly to the Tongue and Inftruments of Speech, and inofculated with the Nerves to go to the Heart and Breast. By which Means there is an admirable and useful Confent between these Parts of the Body; it being natural for moft Animals, upon the hearing any uncouth Sound, to erect their Ears, and prepare them to catch every Sound; to open their Eyes (thofe conftant faithful Centinels) to ftand upon their Watch; and to be ready with the Mouth to call out, or utter what the prefent Occafion fhall dictate. And accordingly it is very useful for most Animals, when furpriz'd, and terrify'd with any Noise, presently to fhriek and cry out.

But there is befides this, in Man, another great Ufe of this nervous Commerce between the Ear and Mouth; and that is, (as one of the best Authors on this Subject expreffeth it) (z), "That the Voice may correfpond with the Hearing, and be a kind "of Echo thereof, that what is beard with one of "the two Nerves, may be readily expreffed with the "Voice, by the Help of the other."

Thus

(y) Hic pofterior Nervus extra cranium delatus, in tres_ramos dividitur, qui omnes motibus patheticisinferviunt. Primus

-mufculis Auris impenditur. Proculdubio hujus actione efficitur, ut animalia quævis, a fubito foni impulfu, aures quafi fonum nimis citò tranfeuntem captaturas erigant. Ramus alterverfus utrumque oculi angulum furculos emittit: qui mufculis palpebrarum attollentibus inferuntur; quorum certè munus eft ad fubitum foni appulfum oculos confeftim aperire, eofque velut ad Éxcubias vocare. -Tertius- -ramus verfus Linguæ radicem defcendens, mufculis ejus & offis Hyoideos diftribuitur, adeòque organa quædam vocis edenda actuat, &c. Willis's Cereb. Anat. Cap. 17.

(z) Hujufmodi Nervorum conformatio in Homine ufum alium infigniorem præftat, nempe ut Vox, &c. Willis ibid.

(aa) A

Thus much fhall fuffice to have fpoken concerning the Organ. Let us,

II. Take Notice of the Object of this admirable Senfe, namely, Sound; and fo conclude this Chapter. I fhall not here enquire into the Nature and Properties of Sound, which is in a great measure intricate, and hath puzzelled the beft Naturalifts: Neither will I fhew how this admirable Effect of the divine Contrivance, may be improved to divers Ufes (aa) and Purposes in human Life; but my Bufinefs will be to fhew that this Thing, of fo admirable Use in the animal World, is the Work of

God,

(aa) Among the Ufes to which the Wit of Man hath employ'd Sounds, we may reckon the Inftruments useful in convocating Affemblies, managing Armies, and many other Oca cafions, wherein Bells, Trumpets, Drums, Horns, and other founding Inftruments are used; the Particularities of which it would be tedious to recount: As that the biggest Bell in Europe is reckoned to be at Erfurt in Germany, which they fay may be heard twenty-four Miles; with much more to the fame Purpose. I fhall therefore only for a Sample take Notice of the Speaking Trumpet; the Invention of which is commonly afcribed to our eminent Sir Samuel Morland; but was more probably Ath. Kircher's; at least he had contrived fuch an Inftrument, before Sir Samuel hit upon his. Kircher in his. Phonurg. faith, The Tromba published laft Year in England, he had invented twenty-four Years before, and published in his Mifurgia; that Jac. Albanus Ghibbefius, and Fr. Efchinardus. afcribe it to him; and that G. Schottus teftifieth he had fuch an Inftrument in his Chamber in the Roman College, with which he could call to, and receive Anfwers from the Porter. And confidering how famed Alexander the Great's Tube was, which is faid might be heard 100 Stadia, it is fomewhat ftrange that no body fooner hit upon the Invention. Of this Stentorophonick Horn of Alexander, there is a Figure preferved in the Vatican, which, for Curiofity fake, I have from Kircher represented in Fig. 3. He faith its Diameter was five Cubits, and that it was fufpended on a Supporter.

For the Make of the Speaking Trumpet, and the Reafon why it magnifies Sounds, I fhall refer to Kircher, especially to Sir Samuel Morland's Tuba Stentorophonica, published in 1672.

K

14

Kircher