610 
LECTURES ON HORSES. 
bones ; either because they are the seats of splents or splints, or 
from their own resemblance to splenters or splinters of wood, or of 
other hard splitting substance. The cannon bone constitutes the 
shaft of support of the leg : above it and upon it, with the inter- 
position of the knee, stands the arm ; while its lower end rests 
upon the pastern bone. The splint bones, pyramidal in shape, and 
adherent to the sides of the cannon, taper downward into points, 
or rather terminate in small tubercular knobs, which have no 
resting-places — no articulation with any bone beneath them ; the 
consequence of which is, that the whole of the weight they receive 
in the support they give the body must have been directly trans- 
mitted to the cannon bone, had they not been cemented to its 
sides by a soft elastic substance, something of an intervening 
nature between cartilage and ligament, which admits of their yield- 
ing downward ; — “ descending,” as Professor Coleman’s expression 
used to be — every time pressure from above is imposed upon 
them. And as the superincumbent weight, in accordance with 
the laws of the centre of gravity, bears more upon the inner than 
upon the outer sides of the limbs, so the inner splint bone is fur- 
nished at the knee with an independent joint, i. e. one of the bones 
of the knee-joint rests exclusively upon the head of the inner 
bone ; which is not the case with the bone on the outer side, that 
receiving but a part of the articulation of the bone of the knee 
above it # . . 
This yielding downward or descent of the splint bones on the 
imposition of weight, and of the inner more than of the outer bone, 
and the instantaneous recoil of them or ascent the moment the 
active pressure has ceased, has long, by veterinarians, been re- 
garded as one of many contrivances, operating, after the manner of 
a spring in the limb, to save the animal machine from receiving 
that concussion which otherwise must necessarily result from its 
great action and speed : some of the weight or pressure which, 
otherwise, must all have been received in a direct line by the 
cannon bone, and from it have descended to the pastern, is now 
diverted for the purpose of setting these springs in operation, and 
thereby conferring elasticity and ease on the animal’s move- 
ments. 
Such has been the use ascribed by veterinary schools to these 
bones, and no question that I know of has been raised about its 
propriety, before Sir Charles Bell took it into consideration, and 
expressed his dissent from it. “ I have some hesitation,” says 
Sir Charles, in his Treatise on ‘ The Hand,’ “ in admitting the 
* A reference to these parts in the skeleton will demonstrate what I have 
said. 
