DAILY ROUTINE AND BODY TEMPERATURE. 249 
noon and the second at 9 p.m., the same hours in both cases. The ascent from 7 a.m. 
to 9 a.m. is slightly less steep in C than in A, which might be explained by the 
fact that on two or three occasions in Ithaca the 9 a.m. temperature was taken very 
soon after a walk uphill in hot weather, but the descent from 9 p-m. to midnight is, 
on the other hand, somewhat more sudden. If the Ithaca temperature habit had been 
fixed in the body, there should be some evidence of delay in the rise of the curve C 
and also in its fall, but there is none. These curves A and C resemble each other more 
nearly than any other two, except probably D (Edinburgh) and G (the last half of the 
voyage westward), where the time difference is again four to five hours. 
TABLE III. 
AVERAGE RECTAL TEMPERATURE FOR NINE PERIODS AS STATED IN THE TEXT. 
June19-25,|June27-30.) July 1-4. | July 5-10. | Aug. 3-13. |Aug. 15-20.|Aug. 21-27.) Aug. 28-30.|Sept. 10-14. 
6 a.m. 36°92 36°55 36°95 36°79 36°80 36:93 36°97 non 36°83 
ea 36:90 36°60 36°90 36°94 36°87 36°92 37:12 36°90 36°90 
Se, 37:16 36°80 37°22 3724 36°93 37°15 37°33 36°95 37:10 
Ass 37°45 37:07 37°40 37°46 37°35 37°47 37°60 37°45 37°37 
12 37°63 37°12 37°57 37°58 37°43 37°48 37°67 37°55 37°70 
3 p.m. 37°58 36°90 37°52 37°64 37°65 37°45 37°72 37°40 37°66 
a 37°55 36°87 37°42 37°54 37°52 37°55 37°70 37°40 37°80 
a, 37°60 37:07 37°45 37°46 37°43 37°47 37°58 37°20 37°70 
12 37°42 36°90 37°25 37°26 37°10 37°07 37°32 37°00 37°30 
It might be supposed that after a five weeks’ residence in Scotland the body would 
gradually accommodate itself to the changed conditions, and a Scottish temperature 
rhythm be established. This would be present in the mean of the observations made 
in the Orkney Islands—curve HE; and if this type had been carried westward, then 
at Winnipeg, where the Scottish daily routine had been moved backwards by more 
than six hours, we would expect to find that the curve for Winnipeg (H) should 
show an upward tendency earlier, according to Winnipeg local time, and also decline 
earlier than the Orkney curve (KE). It does appear that the fall sets in sooner, but the 
Winnipeg type represents only a single day, and some accidental variation might 
account for the early decline. The morning rise does not come in any sooner than in 
Scotland. 
In making such comparisons, however, it is essential that the conditions with regard 
to external temperature, meals, mental activity, and particularly muscular movement 
shall be as nearly as possible similar at the two places, and this will be best secured 
if the subject remains at rest in bed, and at the same time abstains from food while the 
observations are being made. ‘The effects of external factors will then be reduced to 
a minimum, and any inherent temperature rhythm present in the body may be 
expected to show itself. Assuming that the Ithaca rhythm has been replaced by a 
Scottish rhythm in the course of a six weeks’ residence in Scotland, then if the latter 
had persisted in the body to any appreciable extent one would expect to find that the 
