C S40 
being rendered fo by fome fuperficial Cavities, and by 
paffages which penetrate into them, the firft of which 
are for enlarging their Surface, and ftrengthening the 
Adhefion of their Membrane to them 5 the other for the 
ingrefs of Blood Vetfels into their Subftance or Cavi- 
ties. The Cavities of the Bones are in fome large, in 
others fmall and numerous, whofe Partitions are formed 
of Plates propagated wholly from thofe Plates, which 
make the fides of the Bones in fuch as havelong Cavities $ 
and in them which are fpongious,frcm Plates which run 
up the whole length of the Bone in that manner. And 
in fome Bones there are Fafciculi of Strings which run off 
from the Plates in the Sides, and make a fort of CanceUt^ 
or Net-work in the Cavity. 
In the Bones there are Blood-Veffels , which ferve 
for their Nouriihment, which are many ; the Arteries 
entering at one end, and the Veins coming out in vaft 
numbers, either at the contrary extremity, or in fome 
intermediate parts: And there are both Veins and Ar- 
teries belonging to the Marrow. 
In the Teeth heobferves a twofold Subftance, one of 
a ftony Nature, which is the Cortical or exterior part 
of (o much of the Teeth as ftandsoutof the Gums 3 the 
other truly Bone, confifting of Lamina or Plates, as the 
other Bones do. 
In the fecond Difcourfe he gives an Account of the 
manner of Accretion, and Nutrition in general, and 
then particularly in the Bones. The Matter, which 
gives an encreafe to the Animal, is originally from the 
Chyle, the Particles of which defigned for Nourifh- 
ment being elaborated in the Maft of Blood, and fo re- 
duced nearer to the nature of a Suctus nutrttius, anddi- 
fpofed for a Separation,are fecerned ft om the faiiguineous 
Mafs, by Glands feated on the Sides of the Arteries all 
over the Body. And here the Author takes occ^fion to 
fpeak of Glandular Secretion; to explain which he 
obferv« 
