52 PROGRESSIVE POULTRY CULTURE 



A SPECIAL STUDY OF INCUBATING EGGS. 



The poultryman who is sufficiently 'progressive to 

 take a three weeks' course of home study in embryology, 

 will thereby lay the foundation for intelligent hatching 

 of chickens. (Such a course will prove interesting as 

 well as instructive and need not be expensive. The 

 sacrifice of a number of eggs and the spending of some 

 time and thought will enable the student thus to learn 

 some very valuable lessons. 



A good egg-tester is a necessary aid in his investi- 

 gations. If electric light is at hand the poultryman is 

 fortunate. Such light is very penetrating. Acetylene 

 gas yields a brilliant, white flame and may be readily 

 obtained by purchasing a bicycle lamp. The calcium 

 carbide used to produce the gas is not expensive. If 

 neither of these forms of light is available, a good 

 kitchen lamp, burning kerosene oil, will answer fairly 

 well. The common form of egg-tester usually furnished 

 with an incubator is simply a tin chfmney made to fit 

 on the burner of a hand lamp. It has an egg-hole at 

 one side on the level of the lamp flame. This metallic 

 chimney is liable to become very much heated when in 

 use. 



A better arrangement, especially if an electric bulb 

 or a bicycle lamp is available, is made of galvanized iron 

 in the form of a cylinder, about six inches in diameter 

 and ten inches high, provided at one side with a branch 

 tube two and one-half inches in diameter and two and 

 one-half inches long, the latter being placed so that it 

 will be on a level with the light. The outer end of the 

 branch tube is covered with a piece of black felt cloth 

 or dark flannel, in which is cut a circular or oval hole 

 about one and one-half inches wide, or just a little less 

 than the width of the eggs to be tested. This piece of 

 cloth is held fast against the end of the tube by a ring 

 of galvanized iron or tin one-half inch wide, which fits 

 closely over the cloth and the end of the tube. Six or 

 eight half-inch holes are cut in the large cylinder an 



