[ 221 ] 
cefs), may be made ufe of without delay, or attend- 
ance to corroborating fymptoms, at lead: till they 
render themfelves more confpicuous and certain than 
I have hitherto been able to find them : and as the 
operation is not at all dangerous, it neither has, nor 
will, I believe, be thought painful by thofe who de* 
fire to recover their heafing. 
'Explanatioji of the References /;z Plate VI. 
A, The cavity of the cranium, containing the cere- 
brum. 
Procefs of the dura mater, called tentorium. 
C, Cavity containing the cerebellum. 
JD, Poflerior procefs of the dura mater. 
£, Tranfverfe fpinous procefs of the.fphenoid bone, 
jp, Orbiter procefs of the frontal bone. 
G, Frontal finus. 
FI, Body of the fphenoid bone. 
/, Spongious fubftance of its body. 
K, Holes in the fphenoid bone, through which the 
3d, 4th, fth, and 6th pair of nerves pafs out of 
the cranium. 
Z/, Sphenoidal finus. 
M, Sella turcica, in which may be feen 
Nj The glandula pituitaria. 
O, Cribriform lamella of the ethmoid bone. 
.P, Cellulae ethmoides. 
Os fpongiofum fuperius. 
Os fpongiofum inferius ; by its concave furface a 
groove is form’d which ferves as a diredtor to the 
pipe of the fyringe, in its courfe.to the tuba eufta- 
chiana. 
Sj Palatine 
