METHODS OF HATCHING CHICKENS 



305 



it is not essential that the temperature of the room be so 

 constant that an underground cellar is necessary. A house 

 above ground, properly constructed, is more desirable than 

 an underground room or cellar. In warm sections of the 

 country it will aid in maintaining a more uniform tempera- 

 ture if the house can be shaded by other buildings or trees. 

 Choice of an Incubator. There are probably half a 

 hundred different incubators in general use, and many of 

 them differ only in name. The essential features of the 



A ISO-EGG INCUBATOR, KEROSENE LAMP HEATED 



majority of incubators are alike. The source of heat is 

 usually a kerosene lamp. Others are heated by gas or elec- 

 tricity. While the source of heat may be the same, the 

 methods of distributing the heat over the eggs varies in 

 different machines. Because of this difference, incubators 

 have been divided into two classes ; the one in which the 

 heat is radiated from a tank of hot water over the eggs, 

 or from hot water pipes ; the other type, in which, the hot 

 air is diffused through cloth or muslin directly over the 



