POULTRY KEEPING 563 



ter and brushed lightly over the eggs just before they are returned 

 to the machine in the morning. The last seems to be a natural 

 method and does not overcharge the egg chamber with moisture. 

 Too much moisture will ruin the hatch, and it is better to err upon 

 the side of too little than too much. A good rule is to note the baro- 

 meter and in damp weather supply very little moisture. As to what 

 is meant by much or little moisture, the writer thinks that a tea- 

 spoonful of water is plenty for 100 eggs in wet weather, while in dry 

 weather an ounce is none too much, this being for a period of twenty- 

 four hours. Or, again, if the machine stands in a cellar, a teaspoon- 

 ful of water will last 100 eggs three days, while in a dry, well-venti- 

 lated room a tablespoonful of water every twenty-four hours will do 

 no harm. The water supplied must be clean and pure and should be 

 warm when it is introduced. Surely with these few hints the opera- 

 tor ought to be able to settle the moisture question for himself. 



Testing. The egg will show signs of hatching within thirty 

 hours of its first exposure to heat. Along about the twenty-eighth 

 hour a point denoting the head and another denoting the heart will 

 appear. About the forty-fifth hour the expert can detect a slight mo- 

 tion of the heart. In about seventy hours the membrane known as 

 the allantois is visible. This envelope is the temporary breathing 

 apparatus of the chick. On the fifth day the streaks denoting the 

 limbs can be seen. On the sixth day the liver can be located, and a 

 slight voluntary motion is observable. By the seventh day the lungs, 

 stomach, and brain show development ; the eyes can be found by the 

 tenth day ; and on the twelfth day feathers begin to form. The bill 

 opens and shuts by the fifteenth day, and the cry of the chick is 

 heard about the eighteenth day. Soon after, or early on the nine- 

 teenth day, the chick bursts the air cell at the end of the egg and 

 begins to use its lungs in breathing. From this time it grows rapidly 

 and soon becomes strong enough to break through the shell. 



While the process of hatching is very interesting, the practical 

 operator need not concern himself with minute details. The eggs 

 should be tested at least three times during the period of incubation. 

 First, as a matter of economy. Eggs not fertile will not spoil for a 

 few days, and they will be as good for the table or feed after a few 

 days in the incubator as after as many days in the nest. Again, eggs 

 that are doubtful can be cooked for food for young chicks or cooped 

 fowls. Another reason why nonfertile eggs should be discovered 

 and removed is that they absorb some heat from the air of the egg 

 chamber and generate none of their own. Again, if nonfertile eggs 

 happen to be old when placed in the tray they are liable to decompose, 

 and, by giving off poisonous gases, foul the air of the egg chamber 

 and poison the chicks in the good eggs. However, it is not wise to 

 disturb the eggs too frequently. Testing upon the seventh, the tenth, 

 and the fourteenth days is quite sufficient. All nonfertile and all 

 doubtful eggs should be removed from the machine as soon as their 

 condition is detected. 



The process of testing is simple enough after a little experience 

 is acquired. It depends upon the appearance of the egg when it is 



