PSYCHROMETRICAL TABLES. 



2. Dry thermometer, t = 88°. 5 F. 



Wet thermometer, i' = 76°. 3 F. 

 Difference, t — t' = 12°.2 F. 

 Page 63, Table gives for t — t'= 12 and t' = 76° = 0.735 inch. 



Add for fraction of t' = 0.3, 0.003 X 3 = 0.009 



Subtract for fraction oU — t' = 0°.2, .0013 X 2 = —0.003 



Force of vapor in the air = 0.741 

 Relative humidity = 55 



Dry thermometer, t = — 4°. 5 F. 

 Wet thermometer, t' = 6°.0 F. 

 Difference, t — i' = 1°.5 F. 

 Page 50, Table gives for t — t'^ 1°.5 and i' = — 6° = 0.016 inch. 

 Subtract for fraction of t' = 0.5, 0.0002 x 5 = — 0.001 



Force of vapor in the air = 0.015 

 Relative humidity = 45 



I 



B 49 



