124 HATCHING AND REARING 



the higher priced ones, as they are sure to be well built and 

 generally have a good reputation. It is poor policy to select 

 a cheap machine which is only good for one or, at the most, 

 two seasons. 



Placing the Incubator. — The incubator should be placed 

 in a cellar, or a room below the ground level. The cellar 

 of a dwelling house, if it can be kept at a uniform temperature, 

 is very satisfactory, but insurance restrictions should be 

 looked into before placing an incubator in a dwelling. If 

 the machine is placed below the ground level, the temperature 

 can be kept more uniform. When a number of incubators 

 are to be operated, a cellar specially constructed for the 

 purpose and at least five feet below the ground is best. The 

 incubator room should be built with masonry walls and a 

 concrete floor, but may have an asbestos or metal ceiling. 

 Such a room is practically fire-proof. The incubator cellar 

 must be well ventilated, and a good arrangement is to have 

 double window sashes, the outer one hinged at the top and 

 the inner one hinged at the bottom. When opened at an 

 angle of 90 degrees the air will circulate through the room 

 without causing a draft to blow on the incubator itself. 



Requirements of the Incubator. — Heat is the primary 

 factor in an incubator, for we must generate by artificial 

 means the heat which in natural incubation would be gen- 

 erated by the hen's body, and this demands a temperature 

 in the incubator of 103 degrees Fahrenheit. It is M'^ell to 

 start with a temperature a little below this, usually 102 

 degrees, and gradually increase it until at the end of the hatch 

 the heat may be as high as 104 degrees. Great variations 

 in temperature are detrimental to the hatch. An excessively 

 high temperature of 108 degrees will kill the developing 

 chicks, while an average temperature of 105 to 106 degrees 

 will bring the hatch off too soon, and leave many dead in 

 the shell. Too low a temperature will cause postponement 

 of the hatch, and but few chicks will be able to break 



