Figure 1.—Showing First Indication of Fertility.
In the Monarch Incubator this required amount can readily be seen at once by the action of the regulating bar. It informs the operator just when he has enough,—when too much and when too little. Keep both lamps and chimneys clean, and have stated periods for turning your eggs, which should be done twice each day. As I said before, an egg-tester is not required with duck eggs, as they are so transparent that the whole process can be plainly seen without in the flame of a common kerosene lamp. If a duck egg is carefully examined, after being subjected to a heat of 102 degrees for twenty-four hours, a small dark spot will be seen about the size of a large pin-head. This little spot, if the egg is gradually turned, will always float over the upper surface of the egg. This is the life germ, and the first indication of fertility in the egg, and is represented in Figure 1.
At the end of forty-eight hours this dark spot will have nearly doubled its size, and a faint haze will appear around its edges a shade darker than the surrounding contents of the egg. This haze is the first appearance of the blood veins radiating out from the germ.
Figure 2 shows how the egg appears at this stage with the air-cell slightly enlarged.
