MILAN 



In Figure 3 is shown the relation between tissue insulation 

 and the three bath temperatures. At all temperatures the Eskimos 

 have significantly lower tissue insulations than the other groups. 

 The Indians and soldiers are similar to each other and indistinguish- 

 able at 33 G. The three extrapolated curves intercept at about 

 36.5 G and at this bath temperature, under the conditions of this 

 study, tissue insulation would presumably equal zero. 



Percent body fat. The mean values for percent fat in the 

 Eskimos, soldiers, and Indians were 6.6, 15.6 and 12.3. Although 

 the Indians and soldiers were not significantly different from each 

 other, the Eskimos were considerably leaner in body build. Coeffi- 

 cients of the regression line of tissue insulation versus percent 

 body fat were 0.847, 0.309 and 0.657 at 35° C, 33 C and 30.5 C 

 respectively. An analysis of covariance was then undertaken in 

 which tissue insulations were adjusted for their regressions on per- 

 cent body fat. At 35 C there were no differences between groups. 

 At 33 C the differences were significant at the .05 level. At 30.5 C 

 the differences were significant at the .01 level. 



DISGUSSION 



These experiments show that there are differences in total 

 body heat loss and heat production between a sample of Eskimos, 

 Indians, and soldiers immersed in temperature regulated baths. 

 Although rates of heat loss and production were unchanging during 

 the 30 minute period of measurement, the most serious criticism 

 of the results of this experiment concerns non-steady state condi- 

 tions, for rectal temperatures were falling. 



It should be noted that there were no inter- group differences 

 in the fall of rectal temperatures despite considerable differences 

 in heat loss and production. In the 33 C bath the differences in 



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