A GUIDE FOR KEEPERS OF POULTRY 205 
that hatch when incubated in incubators, they usually put 
the figure at about 50 per cent. That is, the incubator 
operator who uses a good machine, selects the eggs with 
care and gives the machine good attention may reason- 
ably count on getting 50 chicks from every 100 eggs he 
puts into the machine. It has been estimated that for 
every + eggs put into an incubator one chick may be 
counted on to arrive at maturity. Very frequently a bet- 
ter result is obtained, but it is not probable that the 
average is even this high. 
This seemingly poor result should not frighten any one 
from using an incubator, as a careful record of the eggs 
used for hatching when hens do the incubating would 
show that the difference between the natural and the arti- 
ficial method is not very great. The use of good ma- 
chines and reliable eggs is not all there is to operating 
an incubator. The following concerning the use of in- 
cubators was prepared by special request by J. L. Nix 
of Pennsylvania who, with Graham of Canada, and Dry- 
den of the Oregon Experiment Station, has been giving 
the subject of artificial incubation very close attention for 
several years. Mr. Nix is probably as well known as any 
other investigator along this line, and his experiments ex- 
tend over many years of close observation. As a manu- 
facturer of incubators he has been vitally interested in 
the problems involved in artificial incubation and his con- 
clusions can not be said to go wrong in the matter of the 
showing made in the number of chicks hatched and their 
“livability.” It will be seen that Mr. Nix quotes Prof. 
Graham who has collaborated with him in many experi- 
ments. Mr. Nix says: 
“All those who are interested in raising poultry arti- 
ficially are anxious to secure all the information possible 
