96 Dr. A. P. W. Philip on the 
the sum of the areas of the branches of arteries exceeds that of 
the trunks. We may thus account for the supply of fluids to 
secreting surfaces, and fer a certain power of the nervous system 
remaining after death; and when the vis @ tergo has wholly 
ceased, except as far as it depends on mere elasticity, and the 
action of very small vessels. 
It remains to be ascertained, whether the nervous power is 
capable of raising the temperature of the blood after the senso- 
rial power is withdrawn. The maintenance of the temperature 
of the more perfect animals, seems, from facts already referred 
to, so immediately to depend on the state of the circulation, 
and to be so generally proportioned to its vigour, that we can- 
not, I think, adopt a better means of answering the question 
before us, than by ascertaining, whether supporting the circu- 
lation by artificial respiration after death occasions the dead 
animal to assume more slowly the temperature of the surround- 
ing medium. On this subject there has been considerable differ- 
ence of opinion. The 64th and two following experiments of 
the above-mentioned Inquiry seem to point out how this differ- 
ence may have arisen on the supposition that all the experiments 
which have been made on the subject are correct, which we have 
every reason to believe them to be. It is evident, that all the 
air thrown into the lungs beyond what is necessary to effect the 
proper change on the blood must tend to reduce the tempera- 
ture, in proportion as that of the air is less than that of the 
animal. The living animal receives but little air into the lungs 
at each inspiration, and it is impossible, after death, just to throw 
in the quantity which the blood still requires, and no more. 
It appears from the experiments last mentioned, that when 
the lungs were inflated from twenty-five to thirty times in a mi- 
nute, the inflation acted as a cooling process ; but that when they 
were inflated only ten or twelve times, the animal cooled more 
slowly than another under the same circumstances left undis- 
turbed: and what particularly points out that artificial respiration 
tended in these experiments to maintain the temperature is, that 
when it was employed, the temperature was sometimes found to 
have risen (in one instance nearly a whole degree,) between the 
