ON INCREMENT OF ANIMAL HEAT. 
425 
We were careful in observing microscopically the blood 
taken during life from animals showing increment of animal 
heat. We took mixed or capillary blood, and Dr. Sedgwick, 
with great care and nicety, got specimens of it at once in the 
field of the microscope. The phenomena are the same as 
have been so often observed in the blood of men suffering 
from increment of heat during inflammatory fever. The 
corpuscles run together in firm rolls, and by aggregation 
produce a surface almost uniform, through which, in channels 
made by separation of rolls of corpuscles, a thin exudative 
fluid freely courses. The appearance, indeed, is like that of 
blood coursing through the capillary canals in the foot of the 
frog, and might, at first glance, be mistaken by any one who 
had not seen the corpuscles aggregate. You will find on the 
microscope table specimens of the blood prepared for exami¬ 
nation by Dr. Sedgwick. Lastly, in respect to the blood, 
the colour of the venous is raised, under increment of heat, 
towards the colour of arterial blood. 
In every sense—in respect to colour, in respect to separa¬ 
tion of fibrine, in respect to running together of the corpuscles, 
the blood, during induced inflammatory fever, is the same as 
is the blood of the patient who is suffering from ordinary 
acute inflammatory fever. 
Other Visceral Organs .—The large abdominal organs in cases 
where the increment of heat is rapidly induced are found free 
of congestion and rather floidd, but they show no indication 
of physical disorganisation. In cases where the increment of 
heat is slow, and where there is separation of fibrine from 
arrest of circulation through the right side of the heart, slight 
congestion of the abdominal organs may exist. There is con¬ 
gestion of kidney in the cat which we have examined to-day. 
In the cat and in the rabbit the urine, if any be in the bladder, 
is found richly charged with albumen. A specimen of this 
kind, with the albumen precipitated by heat and nitric acid, 
is on the table. 
There are many matters of detail which might be added 
to what I have now spoken were there time for details. There 
are also many new paths into which we could strike. I could 
lead you, for example, at once to the proof of the many 
ways by which increment of animal heat may be induced 
without exposing the body to the direct action of air raised 
in temperature. But to-day I must rest content in endea¬ 
vouring to bring out, and as I hope clearly, these two leading 
truths:— 
Firstly. That the fatal increment of animal heat is deter- 
