208 



Artificial Incubation. 



[JULY, 



lings out of 2,669 fertile eggs) ; and hot-air machines (40 

 hatches) yielded /I'Si per cent. (2,618 chickens and ducklings 

 out of 3,661 fertile eggs). By these figures the greater capacity 

 of the latter will be apparent. 



Taking the different types of machines operated during the 

 period. Table IV. gives the comparative results, and, it is 

 interesting to note, with the exception of one (F), the close 

 approximation between the various tank and hot-air incubators 

 respectively. It will be seen that in Class C more birds were 

 hatched than in A, B, and D combined, due to the fact that 

 whilst in the latter all are of 50 to 120-egg capacity, the 

 smallest of the former is for 120 eggs, ranging up to 220 

 and 360. 



TABLE IV.— incubator RESULTS. 



Class of Machine. 



No. of 

 Hatches. 



No. of 

 Fertile Eggs. 



No. of 

 Chickens 

 Hatched. 



Percentage of 

 Fertile Eggs 

 Hatched. 



A 



27 



1,374 



1,060 



77-14 



b 



20 



1,069 



814 



76-14 



C 



27 



2,933 



2,101 



71-63 



D ... 



7 



480 



335 



69-79 



E 



5 



248 



182 



73-38 



F 



3 



226 



139 



61 -06 



The question is frequently asked, apart from the class of 

 incubator, whether one size gives better results than another ? 

 Smaller poultry-keepers naturally prefer those with a modest 

 capacity, and would rather have four holding 50 eggs each than 

 one of 200, as the former can be filled and started whilst the 

 eggs are fresh, and there is not the same loss of power as 

 when a big machine is only partly filled. The figures shown 

 in Table V. give the comparisons. It is surprising to find 

 that whilst the smallest sized incubators (50 eggs) have given 

 the best results, the second best is the largest of all (360 eggs)^ 

 and the lowest place is taken by the 220-egg size. It is true 

 that the 360-egg size was only partly filled on the two occasions 

 it was operated, but that is equally correct with the 220-egg 

 size, for during the eight times these were operated, on one 

 occasion alone had they more than 200 fertile eggs. If the 

 general experience were that the smallest size of incubator 

 gave such high results over 26 hatchings as 79*48, the gain 



