DOGS, CATS AND POULTRY 
657 
lamp or lantern. (Fig. 99.) In one of these pieces cut an 
opening about three or three and a half inches in diameter, 
just high enough so that when the box is adjusted over the 
lamp the opening is opposite the 
Hght. Cut a piece of heavy black 
cloth about four or five inches 
square sufficiently large to cover 
the opening in the side of the box. 
In this cloth cut a circular opening 
a little smaller than an egg and tack 
the cloth over the opening in the 
box. A very inexpensive but excel- 
lent egg tester is now complete. 
On the evening of about the 
fifth or sixth day take the eggs one 
at a time carefully from the nest, 
place them against the opening in 
the cloth. The light shines through 
the egg, and, being excluded by the 
sides of the tester, enables you to 
see whether or not the germ is de- 
veloping. A fertile egg shows a dark, heavy spot (Fig. 100). 
An unfertilized egg appears clear and watery (Fig. 101). 
Place only the fertile eggs back in the nest and throw the 
others away. 
Fig. 99. A Simple, Effective 
Home-made Egg Eester. 
Fig. 100. A Fertile Egg as Seen When 
Placed Against the Opening of the Tester. 
Fig. 101. An Infertile Egg. 
Keep a strict watch during the time the hen is setting, 
so that accidents that may possibly happen can be promptly 
