C 2415 ) 
{The Skin of this Calf is now in the Repofitory of the 
Royal Society in Grcfham-College, given to the fame 
by Dr. Adams.] 
Give me leave to write one thing which to me is 
altogether new. The boney Cavity of the Ear is cover- 
ed at each end by a Membrane ; the former is called the 
Membrane of the Drum, and the other is direftly op- 
pofite to it ; the outer is ftronger than the inner, fo I 
call them with fubmiflion. They are joined together 
by the handle of the Malleus adhering to the outer, and 
the upper part of the Stirrup to the inner, which by 
the intervention of the Incus and the Orbicular Bone 
make a Chain, and they Teem to be afted and re-acted 
by thefe fmall Bones reciprocally. 
Whether Artifts had any refpe£t to this Original, 
when they firft devifed Drums, I cannot fay ; but no- 
thing can more nearly reprefent the Natural than the 
Artificial does ; the Skins of this anfwering to the Mem- 
branes of that, the Wooden Cylinder to the Boney Ca- 
vity; the found of the Drum would be flat without a 
Hole in the fide, and Nature has given a paflage front 
the Palate to the Ear. The Skins of the Drum would 
leflen the found, if they were not kept on the ftretch ; 
fo would thofe of the other flag, if the handle of the 
Hammer and the Stirrup keep them on not the Tenfe. 
This inner Membrane is clofely ftretch’d before the 
Labyrinth, the tor amen rotmdum, and the paflage into 
the Cochlea, (\ omit the Foramen Ovale, becaufe the Foot 
of the Stirrup exa&ly fhuts it], that fo the found may be 
the bigger upon its approach to the Nerves. The Stir- 
rup is generally broke in diflefting tire Ear, patriculady 
that Cover which goes over the Bone on each fide ; but 
if it be carefully open’d, the Stirrup is entirely cover’d 
with a Membrane, which forms a Cavity flatly Oval, 
and the infide is Excavated. 
Norwich^ December , . x 8, 170 6. 
V -rip 
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