44 J- Lindhard. 



the skin temperature corresponds with tliis fall. As most people 

 sleep in a cold room and with uncovered head, the temperature of 

 the head will be lower in the night than in the day; otherwise the 

 skin temperature will depend upon purely outer conditions. 



As stated several times above, the rectal temperature is 

 directly dependent on the variations in the metabolism of the body and 

 only to a small extent on external or purely local conditions. If 

 this is correct, it should be possible to construct the main features 

 of the curve of day and night variations for an [individual whose 

 work and mode of life is known. And then, just as a clergyman, 

 a navvy and a sailor have very different kinds of work, unequally 

 distributed over the hours of day and night, it follows that a "nor- 

 mal" curve of the variations of the rectal temperature is without 

 any connection with reality. 



The accompanying diagram (p. 45) shows day-curves derived from 

 measurements on 3 different individuals under different conditions. 



The first three are variants of the curve with 3 maxima, which 

 is the usual curve on days with sedentary work, as shown on fig. 1. 



In the first the temperature in the forenoon is heightened owing 

 to bodily exercise, the subsequent rise after a meal between 12 and- 

 1 is therefore but slight; owing to bodily exercise and a small extra 

 meal there is in the evening a rise instead of the usual fall. 



In the second case the rise after the last meal is absent, or i& 

 not seen at any rate in the curve. The temperature was not meas- 

 ured immediately before and after the meal. The evening temper- 

 ature is raised for the same reason as in the first case. 



In the 3rd curve there is an unusual rise between 1 and 3 p.m.; 

 it is due to a walk on land. 



The last two curves, which follow a course quite different from 

 the previous, are derived from days passed in hill-climbing and 

 sedentary work. Both begin with a rise of temperature corresponding 

 with the ascent to the place of work; there is then a great fall 

 while standing still at a low temperature and in a slight wind; and 

 finally a rather steep rise, not reaching so high however as the rise 

 in the forenoon, due to the descent from the hill. 



It appears from these two curves that a day passed in an unusual 

 way gives an unusual curve, but the form of this curve is also seen 

 not to be accidental, there being an unmistakable agreement between 

 the two curves. 



The sailor, whose time is divided into a peculiar 48 hours' 

 routine, displays an exceedingly irregular curve of temperature. In 

 his case it is dependent on wind and weather when the hard and 



