NATURAL AND ARTIFICIAL INCUBATION 



79 



instances some of the mammoth machines are heated by- 

 electricity. 



Hot-air and hot-water machines are both used success- 

 fully. The hot-water type of incubator will hold its heat 

 longer than the hot-air machine in the event that the lamp 

 goes out. The possibility of such an accident is, however, 

 too sUght to be worth considering when the incubator is 

 attended to properly. 



Mammoth machines are becoming quite popular and 

 are used extensively both in the day-old chick business and 



Figure 78. — A mammoth incubator with a capacity of 2,400 eggs. 



in custom hatching. Their capacity runs from 1,500 to 

 10,000 or more eggs. These machines are built in sections, 

 consisting of several compartments, each section holding 

 about 2,000 eggs, the size varying in different makes. Small 

 individual machines of from 150 to 400 eggs capacity are 

 generally used when an incubator capacity of less than 

 2,000 eggs i-s desired. 



Selection of the incubator. There is a large variety of 

 rehable makes of incubators manufactured so that no one 

 incubator can be recommended in preference to all others. 

 Cheap machines are usually not economical to buy, as they 

 are less reliable, require more attention and wear out more 



