122 W. A. Osborne: Wd-Bulh and Kata Thermometers. 



data, expressed in seconds, for the cooling of a wet Kata from 

 lOOo F. to 90o F., may be taken as illustrating this. Date— Dec. 

 28th, 1915. 



I found, indeed, that it was easy to obtain, especially, as I have 

 said, in hot, dry weather with unsteady wind, greater variations 

 in the wet Kata reading than it was possible that the state of the 

 body could parallel. In fact, theory would suggest that the bulb of 

 the Kata should approximate in size, shape and water equivalent 

 to the human body if correct values are to be obtained. Of course, 

 a series of readings in fairly quick succession could be taken with 

 the present Kata, and the average computed, but this would be 

 tedious. On the other hand, in calm weather, also when the wind 

 was moderately steady, I obtained consistent readings. 



More experience is necessary before I can venture to come to a 

 conclusion. Yet, so far as my observations go, I feel that for 

 estimating air conditions in mines and buildings, and possibly 

 sheltered outside places where variations in air velocity are not of 

 much magnitude, the Kata-thermometer is the better instrument. 

 Very probably, too, it could be used profitably in those tropic areas 

 where calm weather is the rule. But for ordinary climatological 

 , purposes I still feel that the wet-bulb record is of high value. 



