202
Reflection upon
The Instruments by which Sounds are conveyed from the Drum to the Auditory Nerves in the inner Cavities of the Ear, were very little, if at all, known to the Ancients. In the First Cavity there are Four small Bones, the Hammer, the Anvil, the Stirrup, and a small flattish Bone just in the Articulation of the Anvil and the Stirrup. It is now certainly known, that when the Drum is struck upon by the external Air, these little Bones, which are as big in an Infant as in adult Persons, move each other; the Drum moves the Hammer, That the Anvil, That the Stirrup, which opens the oval Entrance into the Second Cavity: None of these Bones were ever mentioned by the Ancients, who only talked of Windings and Turnings within the Os Petrosum, that were covered by the large Membrane of the Drum. Jacobus Carpus, one of the first Restorers of Anatomy in the last Age, found out the Hammer and the Anvil, Realdus Columbus discovered the Stirrup, and Franciscus Sylvius the little flattish Bone, by him called Os Orbiculare; but mistook its Position: He thought it had been placed Sideways of the Head of the Stirrup, whereas Monsieur du Verney (l)(l) Traité del' Organes de l'Ouye. Paris, 1683. finds that it lies in the Head of the Stirrup, between that and the Anvil. The
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