some Experiments in Climatological Physiology. 351 



(iii.) A sufficient number of experiments to establish an 

 average condition or a series of average conditions 

 corresponding to such variations as sex, colour, 

 race, etc. (norms for sex, etc.). 



(iv.) And thus the measure of the variation from any norm 

 or series of norms is ascertained. 



With such material available the study of special cases 

 and the determination of special physiological data will 

 become possible, though obviously the undertaking is a con- 

 siderable one. The magnitude of the various numbers and 

 the degree of uncertainty indicate that probably 20-minute 

 observations would be ample, instead of 60-minute ones. 



With regard to special conditions, it may be remarked that 

 the data should include both mean and extreme conditions, 

 and are especially important where any physiologically labile 

 condition supervenes. It is only with a series of properly 

 deduced norms that the meaning of individual departures 

 therefrom can be unequivocally traced, and the magnitude 

 of the discrepancy of individual results as shown in the 

 preceding tabulations of the data are a sufficient proof of 

 this. 



The suggested establishment of norms, for the purpose of 

 critically studying individual or group deviations therefrom, 

 evidently requires thai physical conditions shall range 

 tlirough the following, viz., measurement of losses : — 



(i.) (a) In still air, (Jj) air in medium, and (c) in rapid 

 movement, each with three widely different degrees 

 of dryness, 

 (ii.) (a) Air of low temperature, (b) medium, and (c) high 



temperature, each with great diversity of dryness, 

 (iii.) A special series at very low temperatures, 

 (iv.) A special series ranging from say 30° to 45° C, viz., 

 in the range where the labile conditions occur in 

 still air, and with medium and high wind velocity. 



Finally, it may be observed that if, as appears to be the 

 case, all the losses can be put in the form a + bT£ with 

 sufficient approximation (except at critical temperatures, etc.): 

 then for the empirical representation of results or for small 

 corrections for given ranges that expression is of practical 

 value. 



