13 



temperature, the amount is 



ami dry bull is is greatest, 

 ami it increase- as these dif- 

 i'eivnces become less, as we 



by Diagram "2, where 

 the lines descend from left 

 to right. The rate of de- 

 scent is similar at different 



temperatures, as we >ee the 

 di-.-viidiiig lines are parallel, 

 l)iit they become nearer to- 

 gether as the. temperature is 

 less. In this diagram, the 

 degrees on the oblique lines 

 are those of temperature i:i 

 the open air. It' \ve mi a. 

 niv the vertical distant < 



tWeell the-e oblique HlH'S, \VC 



would have a M-ries <>(' num- 

 bers increa.-ing at a gaining 

 rate, which might be :-hown 

 by a curve something like 



those of'the preceding figure, 

 fi!). The Relative Il.nnnl- 

 itij. This is the jn m ntmje 

 iil'iititr<i{i<>ii, 100 being com- 

 plete saturation, as in a i ^g 

 (when the air can hold no 

 more moisture in invisible 

 formt, and being com- 

 plete dryness. In our cli- 

 mate, we never iind the air 

 absolutely dry without arti- 

 ficial means. The degree of 

 relative humidity also de- 

 pends on the temperature, 

 and with a given distance 

 between wet and dry bulbs, 

 it is greatest a^high temper- 



least when the difference between wet 



1. Alisiilutc Ilunii'lity at different Tcini>crn- 

 ! liifT'-reiiix- between wet and dry Balbt 



lieill;,' collStUllt. 



J. Alisolut" Uuini'lity at fixed Temperatures, 

 tin- DiH'crciicu between wet and dry Bulbs being 

 variable. 



