NO. 6 BODY RADIATION ALDRICH 1 3 



the same part of the skin or clothing. Usually 3 independent mea- 

 sures of the temperature were made, since each required less than 

 ^ minute, and the mean used. 



The observations are summarized in table B. The application of 

 the Stefan formula to obtain the computed temperatures was the 

 same as described under the Abbot-Benedict experiments, except 

 that for Melikeron No. 2 the constants are altered. 



Thus (see fig. 9, also pages 5 to 6), 



R = a(T^*- To') sm' 6 

 where 



Rz= ( constant Melik. No. 2) x C" 



= 4.0X (current in amperes)- 

 o-= 8.20X10"" 

 Ti = absolute temperature of radiator 

 To = al)solute temperature of melikeron shutter 

 ■ '^ n '" ''' (1-83)' r r 



Tben T/=ro^+ 8:^ x:26x IQ-" =^"^ + ^-^5C-X 10" 



From this equation, the value of T"i, the absolute temperature of the 

 surface measured, is determined. 



In examining tal)les A and B, we find that the 4th power formula 

 appHed to the measurements on either skin or clothing yields values 

 as great or slightly greater than the observed temperatures. This is 

 evidence that the skin and clothing radiate as a black body at the low 

 temperatures measured. Cobet and Bramigk (Ueber Messung der 

 Warmestialung der menschlichen Haut und ihre klinische Bedeutung, 

 Deutsches Archiv fiir klinische Medizin, Vol. 144, p. 45 to 60) con- 

 firm this result on the skin, and Leonard Hill (The Science of Ven- 

 tilation and Open Air Treatment, British Govt. Report, 1919, Medi- 

 cal Research Commission) finds both skin and clothing nearly black- 

 body radiators for low temperature radiation. 



In table B, the values in the Radiation Summary were o1)tained Ijy 

 the application of Stefan's formula to the mean temperatures given 

 under Temp. Summary. For example, in table Bi, we have given 



Estimated wall temp. = 21 °o 

 Mean skin tem]x =33?^ 



Then 



= 8.2oxio^"r(273 + 33.7)'- (273 + 21.0)^1 

 = .1131 calories per sq. cm. per minute. 



