( hi ) 
that they who are Deaf, open their Mouths wide, when 
they are defirous to hear more diftindly : But I fee not 
how that can be, for tho’ the Cavity of the Bony part 
of the Aquedudl, in mod of Animals, is proportional- 
ly large enough ; yet its carnous or flelhy Part lyes 
for the mod part fo flat, and its two fides are (b collapsed 
together, that fcarce any Air can be admitted, at lead 
fo far as to be fubfervient to the Hearing, 
. The Ojficles in this as in other Animals 
are three or rather four in number; for 
though I did not procure the Os qaaf/ra»- 
guUre of Du F^ermy, yet I have good reafon to believe' 
it was there ; becaufe there is a confpicuous Sims in the 
extremity both of the Incus and Stapes, where they are 
articulated, fo big as to contain the Head of an ordi- 
nary Pin; and when I confider the Angle which mufl 
have been form’d by the articulation of thefe two Bones,, 
I look upon this fmall Bone to ferve for the fame pur* 
poles as the Patella in the Knee, and Sefamotde Bones 
in the Fingers and Toes. 
The Malleolus is an irregular Bone, and 
doubtlefs has been endow’d with pretty ’ 
large Mufcles, becaufe of the rugofities, 
protuberances and Sinus% obfervable in it. • It has 
a protuberant Head IV. ( i ) four Lines broad, 
next to that a Qrena or femicircular Sinus , (2-^ 
after which the Bone is rais’d , affording a protu- 
berant Margin to an oblong Sinus ( 3 ) for receiving 
the head of the Incus, four Lines broad. The oppofite 
part of this Sinus, or back part of the Bone, is con- 
vex or an unequal rugous Surface, with a great many 
protuberances and depreffions, for the Origins and in- 
fertions of the Mufcles, for the fpace of five Lines 1 
where it forms an Angle, from whence it becomes Flat 
and Smooth, being three Lines broad and reaching four. 
