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 Care of Young Chicks.—The principal points in the care of young chicks are fresh air, freedom from infection by epidemic or contagious diseases, exclusion of insect pests, even high temperature, and abundance of food. The young chick is especially sensitive to low temperatures and must be protected from cold, especially from cold rains. For this reason the chicks, after hatching, must be kept, if it is not summer time, in a room where the temperature can be regulated until they have acquired some degree of strength and vitality. The temperature of the chicken house for the young birds should not be lower than 85 or 90 degrees F.

A temperature of about 102 degrees F. is found very favorable to the development of the chicks in the eggs, although the temperature may sometimes fall to 101 or rise to 103 degrees F. without materially affecting the results. Experiments show that too low a temperature arrests the development of the chick. On the contrary there seems to be no indication that an increase of heat, up to 103 degrees F., has any tendency to kill the chick in the last stages of development. It is found best in all cases to set the eggs in the incubator as soon after they are laid as possible. Where the age of the egg is not known it should be carefully candled, that is, held up between the eye and a light in order to determine its condition. In old eggs, the yolk, on candling, becomes more or less diffused with the white and such eggs are to be rejected for incubator purposes as they are not likely to produce chickens. The fertility of the egg must also be assured before placing in the incubator. An unfertilized egg is so much loss in the incubator since it might have been used for food purposes, since the egg, for marketable purposes, when fresh is just as good as a fertilized egg. It is an observed fact that the complete fertilization of the egg, that is, the proper union of the male and female germ cells, is not always complete at the time the egg is laid, but the mingling of the two elements takes place under proper conditions afterwards. The development will also depend upon the vitality of the germ and its component parts. Just, for instance, as the color of the feathers, the size of the body and the general character of the chick may be inherited from either parent, so the vital qualities are much more strongly shown in some eggs than in others. The proper germination of the egg may also be improved by many of the conditions of environment. In the case of eggs, any slight change which would interfere with the functions of the yolk or albumin, both of which are extremely sensitive to change, would interfere with the growth of the embryo either by depriving it of food or subjecting it to other conditions in which its vitality would be diminished or destroyed. The fertilized egg may be separated from the non-fertilized also by candling. At the Rhode Island station it is found that a very good light for candling is the ordinary calcium carbide bicycle lamp, placed in a proper candling box. This is a strong white light quite equal in power to the electric incandescent light and is not so trying to the eyes.