DAILY ROUTINE AND BODY TEMPERATURE. 257 
VI. Tue Retative Vaturs or Recorps rrom Recrum, Mouru, aNp AXILLA, AS 
INDICATING CHANGES IN Bopy TEMPERATURE. 
As is correctly pointed out by LinpHarp, the term “body temperature” is a 
misnomer. ‘There is in reality no such thing. Most of the heat of the body is pro- 
duced in the muscles and in the organs of digestion, notably the liver, and from these 
it is conveyed by the blood to the other organs of the body. If by body temperature 
we mean the temperature of the warmest organ in the body, it will probably be found 
in the muscle or group of muscles which happens to be most active at that particular 
moment, and this will change from time to time according to circumstances. We may 
correctly speak of the rectal temperature, the mouth temperature, or the temperature 
of the axilla as the temperature of these localities at any particular time, but not of the 
body temperature. However, since the heat produced in the muscles, etc., is distributed 
so rapidly by the blood-stream that the temperatures of the deeper parts of the body 
away from the radiating surfaces do not differ at any one time probably by more than 
some fraction of a degree centigrade in health, the term body temperature may still be 
conveniently used as indicating the average temperature of the deeper and well- 
protected parts of the body. 
Clinically the temperature is usually taken in one of three situations—the rectum, 
mouth, or axilla, and of these it is recognised that the rectum is the best, since it is 
better protected against the rapid loss of heat than either the mouth or axilla, and 
consequently the readings are not so liable to be affected by external and accidental 
circumstances. ‘I'he temperature of the rectum is always higher than that of the 
mouth and axilla and nearer the so-called body temperature. The mouth temperature 
is being used less and less by physicians and the axillary temperature scarcely at all, on 
account of the belief that these are unreliable as an indication of the changes in the 
temperature of the deeper parts, v.e. the body temperature. 
An examination of the charts (figs. 1 to 5) will show the relationship existing 
between the temperatures of these localities under different conditions. In the morning, 
before getting out of bed, the readings for the mouth and axilla are practically the same 
throughout the whole experiment, 7.e. for the same day they are almost identical, both 
being distinctly below the rectum. After the subject arises the mouth temperature 
follows more or less closely the changes in the rectal temperature, the two curves 
running parallel to a considerable extent. The most constant deviation from the 
parallel is found between 9 a.m. and noon, when the mouth falls while the rectum 
‘ises, and this is easily explained. The 9 a.m. reading was taken shortly after 
breakfast, and the local effects of mastication and of warm food act on the mouth 
temperature alone. The rise thus produced quickly subsides, so that the next reading, 
at noon, is lower. 
The relationship between the curves of the axilla and rectum are much less constant. 
The temperature of the axilla almost invariably falls when the subject gets out of bed, 
