0 / Bo N E i. 143 
could plainlydiiHnguifh the circular Wrinkles 
or Circumvolutions encompafilng the Fibres, 
as they are pictured Plate XL Fig. III. 
C H A P. ■ .XIII. 
Of BoffEs. 
U PON examining of Bones with a MB 
crofcope , their fuperficial Part is found 
to confid of a great many fmall Veffels, and 
fome few of a larger Size: which lad, when 
they come to the Surface of the Bone, ap¬ 
pear invefled with, either a Membrane or 
bony Subdance perfe&ly tranfparent. The 
Infide of the Bone has a fpongy or cellular 
Subdance, confiding of long Particles clofe- 
ly united, which are compofed of number- 
lefs fmall Veffels, fome running lengthways, 
and others taking their Courle towards the 
Sides of the bony Particles, which, not- 
with dan ding their great Number of Aper¬ 
tures, are extremely hard, and lie fome par¬ 
allel, and others perpendicular, to the Length 
of the Bone. 
Mr. Leeuwenhoek difcovered, once, in 
a fmall Bit of a Shin-Bone, four or five Vef¬ 
fels, with Apertures large enough for a Silk 
to pais through $ each whereof feerned fur- 
niihed with a Valve, difpofed in .filch a Man- 
L 3 ner 
