on Animal Heat, 
59S 
have been produced by the receiver indicated by the admix- 
ture of the hot and cold water, calculating the quantity of 
blood used from the knowledge of its volume and specific 
gravity, employing the formula given by Professor Robison, 
which consists in multiplying respectively the weight of the water 
and the blood by the change of temperature, and dividing the 
first product by the second, the quotient or specific caloric for 
venous blood appears to be as .812, and for arterial as .814, 
results very similar to tliose I have obtained with the blood 
of the sheep. 
In the remaining experiments, blood with the fibrin present 
was employed, and with this exception they were perfectly 
similar to those already described. 
The blood used to ascertain its time of cooling, w'as ob- 
tained from a sheep; and one day the vein was opened, and 
on the next the artery. The capacity of the bottle employed 
exceeded that of the first by one ounce measure of water; but 
it was equally thin. The air of the room was of temperature 6g. 
Water cooled from 120 to 80 in 118 minutes 
Venous blood in - 1 1 2 
Arterial blood in - - 1 13 
And hence, as the latter w'as of specific gravity 1049, its capa- 
city for heat seems to be as .913, and as the former was of 
specific gravity 1051, its capacity appears to be .903. 
In the following experiment, equal volumes of fluid blood 
and of w'ater were used ; w’hich was easily accomplished by 
means of a thin bottle with a large mouth, to which a cork 
was adapted, with a perforation more than sufficiently large ’ 
to admit the bulb of a very delicate thermometer, and of course 
to allow, when the bottle was filled to the brim, the excess to 
