484 
ANATOMY OF THE HORSE. 
gour: but in old, in which the body is gradually decaying, and 
the powers of* life declining, the quantity of this fluid becomes re¬ 
duced. Mr. Wilson, in his Lectures on the Blood , &c., says, 
that “ fat animals are found to possess less blood than leaner 
animals; and tame animals, which are confined, less blood than 
wild ones.” 
If we take the crassamentum, the solid clot formed by coagu¬ 
lation, and wash it, we shall, by repeated ablution, deprive it of 
its red colour, and find that we have still remaining a tough gela¬ 
tinous substance; which, when broken, exhibits a jibrous ap¬ 
pearance, and on that account has received the appropriate name 
of 
FIBRIN. 
Some, however, call it by a name of much older date ; viz. 
coagulable lymph . Only let us understand that both mean the 
same thing. It may be made, artificially, to assume a more per¬ 
fect fibrous aspect, by stirring the blood as it flows from the body 
during coagulation, or by receiving it into a bottle, and shaking 
it therein while it is congealing. In either case it will be made to 
assume a very similar texture to muscular fibre, which it also re¬ 
sembles in its chemical composition : and the resemblance may be¬ 
come so perfect, that it may seem well to merit the appellation given 
it by the old physiologists of “ liquid flesh.” The similar tough¬ 
ness of consistence which it acquires will not become manifest for 
some days after its coagulation ; for I have found that the crassa¬ 
mentum will continue to contract, and very gradually become 
smaller (at the same time squeezing out serum), even for more 
than a w^eek from the time of the detraction of the blood. 
So singular a phenomenon as the spontaneous coagulation and • 
decomposition of the blood presents, could not fail to attract the 
attention and consideration of those engaged in physiological pur¬ 
suits ; accordingly we find various reasons assigned for it by the 
old writers, and yet no one, even up to the present hour, has 
been able to solve the vital problem. The two most obvious 
changes of condition to which it is subjected are rest, and ex¬ 
posure to air or cold. But, as w r e have just seen, it will congeal 
though it be kept stirred or shaken in a bottle; at the same time, 
let it be observed, that a very brisk agitation will maintain its 
fluidity : an effect arising, probably, from the natural attractive¬ 
ness of the particles for each other being artificially counteracted 
until it ceases altogether. Neither is exposure to air or a dimi¬ 
nished temperature the cause, for blood will coagulate in vacuo ; 
and is, likewise, often found in clots in vessels and cavities of 
the body, with sufficient evidence of its having been so during 
