ORANGE-RED UNDERWEAR. 



537 



pigment of the darkest skin does not by any means approximate the 

 orange-red of the experimental garments in the matter of excluding the 

 chemical rays, and this is the more remarkable when the thickness and 

 close texture of the skin is contrasted with the lesser thickness and loose 

 weave of the undershirt used. This observation is in support of the 

 statement of Doctor Freer, of the Philippine Bureau of Science, that the 

 obstruction offered to the chemical ray by red or similar color is not clue 

 to any inherent quality of the color as such, but varies with the chemical 

 nature of the dyes used. 



One of the earliest and most persistent complaints against the orange- 

 red underwear was that it was hotter and caused more perspiration than 

 the white. If this could be proved and the difference in temperature 

 found to be at all great, the fact would be a serious objection to its further 

 use. In order to determine how much foundation there was for these 

 complaints the following experiments were carried out : 



Experiment No. I. — Two thermometers were first tested by heat and 

 cold to see that they registered equally. 



Experiment No. II. — The thermometers were placed, one behind a 

 screen of orange-red and the other behind a screen of white, both screens 

 being made of the undershirt material. After an exposure of the screens 

 to twenty minutes of direct sunlight, with free circulation of air around 

 the thermometers, both registered 36° C. 



Experiment No. III. — The thermometers were inclosed in equal 

 thickness of the two materials. After twenty minutes the one inclosed 

 in orange-red registered 52° C, while, that inclosed in white registered 

 '±4.6° C. The thermometer inclosed in white attained its maximum more 

 quickly than that in the red. 



Experiments Nos. IV and V. — Thermometers were placed in empty 

 flasks and covered with orange-red and white undershirt material, and 

 in flasks of ice water covered in the same manner and exposed to sun- 

 light. The table below shows the variations in the temperatures, in 



degrees centigrade. 



Table VIII. 



Exposure. 



Air 

 temperature. 



Water 

 temperature. 



White. 



Orange- 

 red. 



White. 



Orange- 

 red. 





°C. 



°C. 



°C. 

 8.0 

 11.0 



13. S 

 16.2 

 19.0 

 21.5 

 23.2 

 27.0 



°q. 



8.0 



10.5 



14.2 



17.5 



20.5 



23.4 



25.2 



29.6 



After 10 minutes __ '_.. 



39.0 

 41.2 

 43.0 

 43.2 

 43.5 

 44.0 



41.0 

 43.5 

 46.0 

 47.0 

 48.0 

 48.2 







After 40 minutes 





After 1 hour _ _ _ 











