296 FARM AND SCHOOL PROBLEMS. 



There should be an incubator and incubation in every school 

 building. 



Principles of Incubation. 



1. The average time for hatching is 21 days. 



2. The average heat required for hatching is 103 degrees Fahr. 



3. The eggs should be turned once each day. 



4. The eggs should be removed and aired each day for a few minutes. 



5. The heat must be uniform. 



6. Heat may be supplied by oil, gas, electricity, or hot water. 



7. Incubator to be in a dry, cool, unheated room. 



8. Incubator must be perfectly level to heat evenly. 



9. The first test of eggs should be made on the sixth or seventh day. 



10. The second test is made on the 17th or 18th day. 



11. Just as the eggs begin to hatch the temperature may be allowed to 

 run up to 103.5 degrees. 



12. When the chicks are coming out rapidly it is advisable to keep up 

 the heat to 104 or 105 degrees. 



13. The natural heat from the chicks when hatching will require less 

 artificial heat. 



14. Eggs of different species of birds will require different periods of 

 time for incubation. 



FIG. 8. 



Dead germ, 7th day Fertile egg, 7th day Infertile egg 



The success of the incubator hatch will depend upon a 

 thorough understanding of its operation and the care with which 

 it is operated. Most failures come from lack of information and 

 from mismanagement. 



Poultry Problems. 



1. Four hundred eggs were placed in an incubator; the cost of the 

 eggs was 20c per dozen ; the cost of kerosene for operating incubator was 

 50c; there was 75 per cent of a hatch; the chicks were sold at 9c apiece; 

 what did the operator receive for his trouble? 



