37 



Table X. Egg Hygrometer in Bottle Containing Air. 



Table XI. Egg Hygrometer under Buff Orpington on Straw Nest. 



During- two hours the sack became dry twice and almost dry again, 

 enough water having thus evaporated to saturate the nest air six times 

 over. Yet the humidity was practically constant from the very first read- 

 ing ! Very different from the behavior in the bottle. Hence we concluded 

 it was impossible for the hygrometer to saturate the nest air. The vapor 

 must be passing from the nest quite rapidly. 



But the clearing away of one objection raised another : since so much 

 vapor is being dissipated, it is possible the close-meshed wire gauze is 

 hindering free diffusion, thus to a certain extent bottling up the vapor 

 around the thermometer. If so the humidity in the "egg'' does not repre- 

 sent that in the nest generally. Before this objection could be satisfac- 

 torily answered it was necessary to begin the humidity determinations 

 under the hens already set. The results are shown in the following table : 



5 Bull. 163. 



