482 
ANATOMY OF THE HORSE. 
at different periods, depending on the state of health and con¬ 
dition of the subject from which it is drawn. In man, the cras- 
samentum may be said to amount to about one-third of the 
weight of the serum; in the horse, the solid will bear nearly an 
equal ratio with the fluid portion. 
In the more perfect, or, as they have been denominated in 
contradistinction to the others, the warm-blooded animals, the 
blood is everywhere found, while circulating in the living body, 
to be of a certain degree of heat; and this it steadily preserves in 
its circulation through the inward parts of the body, uninflu¬ 
enced by the surrounding temperature. In all unexposed parts 
the heat will exceed 100° of Fahrenheit’s thermometer; it has 
been found, however, by experiment, that this degree is not 
equally maintained in the more superficial situations of the body: 
what these variations are we have but little to do with, though 
they may be ascertained by the aid of the thermometer, at any 
time, with precision. But in the lower orders of animals, or 
such as are called cold-blooded, the heat of the blood cor¬ 
responds with that of the medium in which they live. We are 
not, however, to suppose that the temperature of this fluid is 
never subject to variation, even in perfect animals, for it is found 
to be much influenced in them by disease: e. g . in the human 
subject, in whom the heat of the body is, in health, 98°, it has 
been known to rise to 110° during fever; and, in all superficial 
parts, increased heat is one of the essential symptoms of inflam¬ 
mation. 
The heat of the horse’s blood, while flowing into a basin, is 
100°. If the bulb of the thermometer be introduced into the 
wound, the quicksilver will rise to about 101°. The temperature 
of the more superficial parts of the body will, in course, vary 
with that of the surrounding atmosphere. Mr. Hunter found 
that the thermometer, introduced into a wound two inches deep, 
made into the gluteal muscles of an ass, indicated 100°; and 
that the heat of the vagina was the same. The interior of the 
chest of the dog he ascertained to be 101°. 
The colour of the blood is red. Not in all animals, however; 
for in such as are called cold-blooded—in most fish, their gills ex¬ 
cepted,—and in insects it is colourless and transparent. So, like¬ 
wise, it is in parts even of such animals as are warm-blooded ; 
as, for example, in the common • domestic fowl, in which the 
breast and wings are delicately white, while the legs and body 
partake of a dusky red hue. I believe the blood of the horse is 
not so high-coloured as that of a man, and that the latter yields in 
brightness to that of a dog. All this seems to argue that colour 
is not an indispensable property. 
