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Of Winds and Sounds.

For the Parts of a sonorous Body, beifl£put into Motion by Percussion, do vibr a *j e

forward

And moreover it is so disposed, that it is able more fi rn ^to unite and condense, or more laxly to disperse otrify, the same aerial Rays, so as to accommodate >for attemperating a Sound too strong, and aug® eing it when too weak, as Occasion requires.

3. The Meatus Auditorius, consisting partly of a Jtilaginous and partly of a bony Pipe, convejfeJthe ho gtowards the interior Parts, and the Obliquity °* pCanal increases the Superficies, and consequently ^ ^tiplies the Points of Reflection. Moreover, thegular cartilaginous Tongue, by its elastic tre® 0 *^Texture, and erect Position in the Hollow of the Co# ^just over the Orifice of the Auditory Passage, caus eS ’ Jan egregious Mechanism, that all the Rays ofwhich arrive at the Ear shall enter the said Passage ;■prevents their flying out again by any Reflections 5soever. Its tubulous cylindro-elliptical Figure, >serpentine Progress first ascending, then descending’ j,ethen ascending again till it terminates in the M e ® J,of the Tympanum., increases the Reflection and

and causes that all the fonorific Rays shall atj aunited upon the central Point of its End; ^ j fl g0'at the same time all Sensation of a confused androus Sound. g it

4. The Membrana Tympani, or fine Membra ^

"the End of the Meatus Auditorius, is so oblique 1tended across the Passage, as above to make an ° ^Angle, and below an acute one with the said ffl 1 Qi -.Hence the Surface is increased, and render’d m 0 t et ist$pable of tremulous Concussions, and of concenthe Rays upon its middle Point. , c oT

5 % This Membrane being expanded upon tl^jiected with the bony Margin of the Meatus, > s 0 ^d-fore Part (towards the Meatus) concave, f ° t0 th 6behind or on the internal Part* where it is appl‘ edHandleTart of a little Bone, call’d the Mailed ot ^ 0 ji emer, whose Head is moveable in a bony Sinus 0

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