go 



Artificial Incubation. 



[may, 



humidity of the air frequently varies in inverse ratio with the 

 temperature. 



During the year under review the same leading makes of 

 machines were employed as in the previous twelve months. 

 For a portion of the period three other incubators were tested, 

 but only for part of the time, and it would be unfair to include 

 them. Those recorded below are well known, namely, A, Hear- 

 son's Champion ; B, Tamlin's Nonpareil ; and C, the Cyphers. 

 A and B are tank machines and C a hot-air, non-moisture 



75 



to 







Ofal. ~Hoy. ^twfcfti ^y. *otr. 





K 





; \ 







i 



* 









\ J A \ 





• k / \ 



5551 



i 



ffo 1 



iYalc<*<u~i «-y^ y+-(>o «-rf ft-n »s*f s ^ b **> 



Diagram I. 



Variations of Temperature and Humidity in the Incubator House. 



incubator. From Table I. it will be seen that all were equally 

 supplied atmospherically with a large amount of moisture apart 

 from that artificially provided in A and B. Table II. gives the 

 record of each incubator during the entire twelve months, 

 showing (i) the number of eggs placed in the machine, (2) 

 number of fertile eggs as revealed by testing on the seventh day, 

 (3) number of chickens hatched, and (4) percentage of fertile eggs 

 hatched. The fertile eggs alone are calculated in working out the 



