SB CONSTRUCTIVE BEEKEEPING 



condition of body that gives winter's quiet and contentment, it 

 depends wholly upon the temperature of the air surrounding it. 



This minimum body-temperautre has been found to be 57 

 degrees. When the temperature of the air surrounding the bee 

 is below this point energy is used by the. bee to keep its temper- 

 ature up to this safe minimum . 



The instinct of the bee leads it to do things, not wholly for 

 his own individual comfort, but for the good of the colony. For 

 this reason we find the bees clustered when the temjperature of 

 the hive air goes below 57 degrees. The temperature of the 

 cluster may be raised at the center to 90 degrees, the ones at 

 the outside of the cluster are giving their bodies for isolation of 

 the cluster. It is not known if a temperature down to freezing 

 injures these exposed bees. Bees have been revived after ex- 

 posure, for some time to a very low temperature. 



If the reader will keep in mind this relation of temperature 

 to the bees, the effect of humidity of the air on a colony of bees 

 will be better understood. It is evident to every person wintering 

 bees that humidity plays an important part in success or failure. 

 Temperature and humidity are so related to each other that tem- 

 perature controls the absolute humidity of the air at saturation, 

 as the following tabulation shows : 



Vapor wt. per Cu Ft. 

 Temperature at saturation. 



Grains. 



0.54 



10 0.84 



20 1.30 



30 1.97 



40 2.86 



50 4.09 



60 5.75 



70 7.99 



80 10.95 



90 14.81 



100 19.79 



