[] I cannot but admire that our most eminent modern Anatomists should not agree, whether there be any Muscles in the outward Ear of Man or not. Dr. Keil saith there are two; Dr. Drake the same Number; and Dr. Gibson makes them to be four. So also doth Monsieur Dionis, and so did the ancient Anatomists: But Dr. Schelhammer expressly denies there are any, and saith, Seduxit autem reliquos Brutorum Anatome, in quorum plerisque tales Musculi plures inveniuntur; putârunt autem fortassis ignominiosum Homini, si non & his instructus esset, & minùs inde perfectum animal fore. Schel. de Auditu p. 1. c. 1. §. 7. But Valsalva, who wrote very lately, and is very accurate in his Survey of the Ear, saith, Musculi auriculæ posteriores quandoque quatuor, quandoque duo; sed ut plurimùm tres adnotantur; & quando solùm duo se manifestant, tunc unus ex illis duplicato tendine versùs Concham deferri solet. Horum musculorum in numero varietatem non solùm in diversis; verùm etiam in eodem subjecto quandoque vidi——Ex quibus differentiis subortæ sunt Auctorum discrepantiæ in horum Musculorum numero, & positu:——quod non evenisset, si pluries in diversis Corporibus iidem Musculi quæsiti essent. Ant. Mar. Valsalva de Aur. Human. c. 1. §. 6. But Dr. Drake thinks some of Valsalva’s Muscles the Product of Fancy. Mr. Cowper makes them to be three, one Attollent, and two Retrabent Muscles. See Anat. Tab. 12.
[c] Inter cætera [animalia aurita] maximè admirabilis est auris leporinæ fabrica, quod cùm timidissimum animal sit, & prorsus inerme, natura id tum auditu acurissimo, tanquam hostium exploratore ad perfentienda pericula, tum pedibus ceu armis ad currendum aptis munisse videtur. A. Kircher’s Phonurg. l. 1. §. 7. Technas. 2.
[d] Moles have no protuberant Ear, but only a round Hole between the Neck and Shoulder; which Situation of it, together with the thick, short Fur that covers it, is a sufficient Defensative against external Annoyances. The Meatus Auditorius is long, round and cartilaginous, reaching to the under part of the Skull. Round the inside runs a little Ridge, resembling two Threads of a Skrew; at the Bottom whereof is a pretty Inlet, leading to the Drum, made, on one side with the aforesaid cochleous Ridge, and on the other, with a small Cartilage. I observed there was Cerumen in the Meatus.
As to the inner Ear, it is somewhat singular, and different from that of the other Quadrupeds, and much more from Birds, although I have met with some Authors that make it agreeing with that of Birds. There are three small Bones only (all hollow) by which the Drum (to use the old Appellation) or the Membrana Tympani (as others call it) acteth upon the Auditory Nerve. The first is the Malleus, which hath two Processes nearly of equal Length; the longer of which is braced to the Membrana Tympani, the shorter to the side of the Drum or Os Petrosum; the back part of it resembles the Head and Stalk of a small Mushroom, such as are pickled. On the back of the Malleus lies the next small Bone, which may be called the Incus, long, and without any Process, having somewhat the Form of the short Scoop wherewith Water-men throw the Water out of their Wherries. To the end of this the third and last small Bone is tacked by a very tender Brace. This little Bone bears the Office of the Stapes, but is only forked without any Base. One of these Forks is at one Fenestra, or Foramen, the other at another; in which Fenestra I apprehend the Forks are tacked to the Auditory Nerve. These Fenestra (equivalent to the Fenestra Ovalis, and Rotunda in others) are the Inlets into the Cochlea and Canales Semicirculares, in which the Auditory Nerve lieth. The Semicircular Canales lie at a distance from the Drum, and are not lodged (as in other Animals) in a strong, thick Body of Bone, but are thrust out, within the Skull, making an Antrum, with an handsome Arch leading into it, into which a part of the Brain enters.
One Leg of the Malleus being fastned to the Membrana Tympani, and the Incus to the back of the Malleus, and the top of that to the top of the Stapes, and the Forks or Branches of the Stapes to the Auditory Nerve, I observed that whenever I moved the Membrane, all the little Bones were at the same time moved, and consequently the Auditory Nerve thereby affected also.
I hope the Reader will excuse me for being so particular in this Organ only of the Mole, a despised Creature, but as notable an Example of God’s Work, as its Life is different from that of other Quadrupeds; for which Reason it partly is that I have enlarged on this part differing from that of others, and which no Body that I know of, hath taken much notice of, and which is not discoverable without great Patience and Application; and partly because by comparing these Observations with [Book VII. Chap. 2. Note (d)], we may judge how the Sense of Hearing is performed.
[e] Among many Varieties, both in the inner and outer Ear, those which appear in the Passage into the Rock-Bone, are remarkable. For in an Owl, that perches on a Tree or Beam, and hearkens after the Prey beneath her, it is produced farther out above than it is below, for the better Reception of the least Sound. But in a Fox, that scouteth underneath the Prey at Roost; it is for the same Reason, produced farther out below. In a Pole-Cat, which hearkens strait forward, it is produced behind, for the taking of a forward Sound. Whereas in a Hare, which is very quick of Hearing, and thinks of nothing but being pursued, it is supplied with a bony Tube, which as a natural Otocoustick, is so directed backward, as to receive the smallest and most distant Sound that comes behind her. Grew’s Cosmolog. Sacr. lib. 1. c. 5. §. 6.
[f] The Texture of the Tragus and Antitragus, is softer than that of the Helix, which serveth gently to blunt, not forcibly to repel the Sound in the Concha.
[g] Dr. Gibson’s Anatomy, Chap. 22. Book III.
Those whose Ears are cut off, have but a confused way of Hearing, and are obliged either to form a Cavity round the Ear with their own Hands, or else to make use of a Horn, and apply the end of it to the inner Cavity of the Ear, on order to receive the agitated Air. ’Tis likewise observed, that those whose Ears jut out, hear better than flat-eared Persons. Monsieur Dionis’s Anat. Demonstr. 8.