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DAIRY LABORATORY GUIDE 



thermometer is, of course, lowered more or less accord- 

 ing to the rate of evaporation from the wick, and this 

 rate is affected by the relative humidity of the air. 

 In a saturated air there could be no evaporation and 

 the thermometers would register alike; in a very dry 

 air the evaporation would be rapid and the difference 

 of temperature indicated would be considerable. 



TABLE SHOWING THE RELATIVE HUMIDITY IN THE 

 Am OF CURING ROOMS. (King.) 



Directions : Notice that the table is in three-column 

 sections. Find air temperature in first column, then 

 find wet bulb temperature in second column, same 

 division. In third column opposite this is relative 

 humidity. 



Example: Air temperature is 50 in first column; 

 wet bulb is 44 in second column, same division. 

 Opposite 44 is 61, which is the per cent of saturation, 

 or relative humidity of the air. 



FAHRENHEIT SCALE 



