lOlS] Death of Chicks ix Artificial I.vcubatiox 145 



all chicks, failing to hatch because of some deformity due to abnormal 

 conditions of development conld not be certainly determined. De- 

 formities in chicks developed under hens show that these irregulari- 

 ties are not confined to artificial incubation. 



As to application, regulation, and cost of oxygen, it was found that 

 oxygen was most conveniently handled in small cylinders, capacity 

 forty gallons of gas. The gas was passed through water, and by 

 counting the bubbles, computing the cubical contents of incubator, 

 and analyzing the air it was found a simple thing to regulate the flow 

 of gas so as to keep the air in the incubator close to normal. :N"ote 

 experiments J and K. The oxygen was introduced in the current of 

 warm air entering the incubator. The quantity required in one case 

 was forty gallons, which cost two dollars, but in another experiment, 

 K, which gave good results, approximately thirty gallons were used! 

 If we take forty per cent as an average figiire of loss from death in 

 shell after the eighteenth day, we would in experiment J have secured 

 107 chicks instead of 162. If the oxygen used was the cause of the 

 55 additional chicks getting out of the shell, we have a right to say 

 that the two dollars spent for oxygen was a good investment, for this 

 is less than three cents per chick. If they were high-bred stock they 

 would be worth ten times this amount. 



One of the interesting features of these experiments with the 

 oxygen-fed incubators was the comfort of the chicks during the last 

 days of the hatch; no crying, no panting, no running about. The 

 absolute quiet was proof that the chicks were enjoying the oxygen. 



There seems to be reasonable grounds for believing that lack of 

 oxygen in incubators during the last two days of hatch has nmch to do 

 with the heavy losses in artificial incubation. Certainly the result,^ 

 reported Avonld justify fnrtlier investigation hy owv experiment 

 stations. 



Daviu.so.n Coli,kc;k, N. C. 



