( »*4 ) 
is betwixt the Procejfus Petrofus , and two pofttrior ‘Troceffus Cli- 
noides ; whereas here tis betwixt the Procejfus Petrofus and Center 
of the Bafe of the Scull, on each fide abouE j Inches diflant from 
Seventh? dir. ether. 1 he feventh Pair is for the Tfjrvtu Auditoriut 
(m.m.) being fituated in the Procejfus Petrofus (S.S.) And here ’tis 
obfervable, that from the fide of the Hole where the Carotid 
Artery ( l. 1 .) pafies toward the Os Petrofum , there is an Hole which 
runs about i \ Inch outward, forms an Angle, and then palling 
by the Sides of the CavitasTympani ( e .) runs llreight downward 
and penetrates the Scull (l. ) This I take to be the Hole for the 
hard Portion of the Nervits Auditorius , which does not here as 
in other Animals, pafs in at the Hole of the Procejfus Petrofus 
with the foft Portion ; but as it proceeds from the Brain, goes 
along the Sides of the Carotid Artery to this Hole. This hard 
Portion, as I told you, was much bigger as we trac’d it running 
forward above the Temporal Mufcle, and going to the upper Lip 
Eighth Pair, to be afterward difpers’d in the PrebofcU. The eight Pair is for 
the Internal jugular Vein, and par vagum, which palfes out at the 
A Hole for fame Hole ( n. «.) And the Ninth Impar , is for the Spinal Marrow t, 
the Spinal of which already. And thus we have given an Account of all the 
Marrow. Parts 0 f the inner Surface of the Scull. Now we come to the 
Confederation of 
The Ear , whofe Parts are, ift. The Meatus ^Auditorius, or 
that Dm# which runs from an Orifice on each fide of the Head 
Tab 3. Fig. (k^) whereof formerly, to the inner Table of the Scull, termi- 
2. nating in the Os Petrofum ( S .) being of a Cylindrical Figure (b. b ) 
13- having the CcRules arifing from it on all fides (c. c. fkc.J ’Tis in 
Fig. 1 2. length from the External Orifice to the Crena for the Membrana 
Fty. 10. Tympani (b.) 9 \ Inches, and about 1 Inch Diameter throughout 
the whole Extent. Its Sides are compos’d of a firm folid Bone, 
and little thicker than an Halfpenny. Next is obfervable the 
Crena for the Membrana Tympani , in Circumference 2 Inches } : 
After which is to be feen the Cavitas Tympani , confiflingof two 
Parts-, the firft whereof (c. c.) is i Inch deep, {freight down 
from the forefaid Crena, endued with a great many Cellules , 
diftinguifh'd from each other by feveral ofieous folid Lamina , 
irregularly difpos’d, which could not be fo well reprefented in the 
Figure. Thefe Excavations were about two or three Lines, or 
or i Inch deep. The next Cavity ( d-) is of a Surface more 
fmooth, arifes much higher than the former, and runs toward 
the outer Table, having feveral Semicircular Lines running 
acrofs. 
