8 





BULLETIN 4114, U. S. DEPARTMENT OF AGRICULTURE. 



Frequent readings of the humidity in the rooms should be made, once 

 every hour in the beginning, by means of the sling psych rometer. A 

 record should be kept of these readings from the beginning to the 

 cud of the curing process. A convenient form for recording these 

 data is as follows : 



Humidity record of I he carina room. 



Date. 



Time. 



Air 



tempera- 

 ture. 



Psychrometer 



readings. 



Relative 

 humid- 

 ity. 



Dew 

 point. 



Outside air. 



Dry 



bulb. 



Wet 

 bulb. 



Tempera- 

 ture. 



Humid- 

 ity. 



Dew 

 point. 























, 































1 











Fig. 5. — Side view of the humidifier, showing details of construction. 



A covered jar of distilled water should be kept in each room for 

 moistening the cloth on the wet bulb of the sling psychrometer. The 

 air temperature of the rooms should be determined from standard- 

 ized thermometers hung in a permanent position in each room. 



In practice it has been found that the number of humidity deter- 

 minations in the rooms can eventually be greatly reduced. Usually, 

 during ordinary weather, three readings each day will give the 

 necessary information for use in handling the humidifier. With 

 fluctuating weather conditions the readings will of necessity be 

 made more often. It is very desirable to make at least one, prefera- 

 bly more than one, daily determination of the air conditions outside 



