802 



ANIMAL HEAT. 



the two chief meals were at 11 P.M. and 6 A.M. Notwithstanding the 

 inversion of daily routine, Mosso found that the morning rise still took 

 place about the same time, and, as the following curves (Fig. 80) will 

 show, the daily variation was not inverted, although the sleep during 

 the day caused a fall, and getting up in the evening a marked rise, in 

 temperature. The effect of the experiment was to disturb the regularity 

 of the daily variation, but on the fourth day the influence of the sleep 

 during the day was most marked, a fact which seems to indicate that, 

 if the habit were long continued, a tendency to inversion would be 

 observed in the daily variation of temperature. 



FIG. 80. Daily variations in temperature observed during U. Mosso's experiments. 



Buchser, 1 an engineer, who was accustomed to sleep during the day 

 and work at night, found that his average morning temperature was 

 37 0> 25, while his evening temperature was 36 0- 8. 



There are secondary causes of the daily variation. The periods of 

 high and low bodily temperature more or less correspond with the times 

 of day when the external temperature is high and low respectively. 

 Further, there appears to be a certain periodicity, the result of long-con- 

 tinued habits of life, stamped upon the processes which regulate tem- 

 perature. This is shown by the fact that the daily variation still 

 persists, although it may be slightly modified, during a period of fasting 

 or night-watching, 2 and a similar daily variation is observed in the 

 respiration and pulse, 3 in the discharge of urea, 4 and in the capacity 



1 Quoted from Carter, Jo urn. Nerv. and Ment. Dis., N.Y., 1890, vol. xvii. p. 785. 



2 Jiirgensen, "Die Korperwarme des gesunden Menschen," Leipzig, 1873; Ogle, St. 

 Georges Hosp. Hep., London, 1866, vol. i. p. 228; Crombie, Indian Ann. Med. Sc., 

 Calcutta, 1873, vol. xvi. p. 597; Liebermeister, "Handbuch d. Path. u. Therap. des 

 Fiebers." 



3 Lichtenfels and Frohlich, Denkscliriften d. Jc. Akad. d. Wissensch. Wien, 1852, Bd. iii. 

 Abth. 2, S. 113 ; Neuhauss, Virchoivs Archiv, 1893, Bd. cxxxiv. S. 365. See also this 

 article, p. 813 ; Bosanquet, Lancet, London, 1895, vol. i. p. 672 ; Damrosch, Deutsches 

 Arch.f. klin. Med., Leipzig, 1853, S. 342 ; Jousset, Arch, de med. nav., Paris, 1883, tome 

 xl. pp. 284-5 ; Chossat, Mem. Acad. d. sc. de I'Inst. de France, Paris, 1843, tomeviii. p. 540. 



4 Weigelin, Arch.f. Anat., Physiol. u. ivissensch. Med., Leipzig, 1868, S. 207. 



