48 



J. Lindhard. 



as the transition had been accomplished; after 5 — 6 days only a few 

 were still a little indisposed to work, sleeping less well in the "night" 

 and becoming sleepy at various times of the "day". The function 

 altered with the greatest difficulty was defæcation; for a few it took 

 about a week before this occurred at the usual time, for one (rarelj-^ 

 quite free however from indisposition) it took even till the end of 

 the experiment. As the end of December was not well-adapted to 

 the experiment, owing to the irregular mode of living characteristic 

 of Christmas, w^hich cannot be dispensed with even in those latitudes, 



8 p.m. 



12 



12 



37°, 



^б" 



37" 



36' 



37° 



36' 



37« 



X 



^. 



p. m 



'07 



11-12 



J ^^^07. 



, 12 13 



J ^^^07 



J 2^07 



Fig. 8. 



I restricted the experiment as much as possible, taking the necessary 

 days for control afterwards. 



Thanks to the easy transitions, the time proved sufficient. On 

 the 2nd of January the change began, on the 4th we were on the 

 new system; on the 9th I began the measurements of temperature 

 for my own part. As late as the 11th one of the individuals exam- 

 ined had an irregular curve; but on the 12th his curve also had 

 adopted the usual form. On the 15th the return began, and on the 

 18th we were again under normal conditions. As the second return 

 was attended by the same phenomena as the first, appearing especi- 

 ally in the same persons who had presented difficulties on the 



