126 POULTRY BREEDING 
started all right will show a dark spot partly surrounded 
by a dark-colored ring, without any appearance of veins 
such as are seen when “the spider” appears. These eggs 
should also be removed. Germs may continue to die from 
time to time up to the time the chick is full-formed, but 
no description can make their appearance plain to the be- 
ginner. Learning to recognize dead eggs after 10 days 
is a matter of experience. Usually the expert operator 
can detect a dead egg as soon as he takes it in his hand, 
as he senses the difference in temperature between an egg 
that is dead and one that contains a living embryo. Eggs 
should be tested the 5th and the 10th days after they have 
been put in an incubator or under a hen. 
EGGS, RELATION OF FEED TO.—In a bulletin 
issued by the Oregon Agricultural College, Prof. Dryden 
says: “The hen puts into the eggs what the poultryman 
puts into the hen. If the cabinet maker puts oak lumber 
into a furniture factory it will come out oak but in a dif- 
ferent form. If we put wheat or corn into a hen it will 
come out wheat or corn but in a different form. There 
is a close relationship between the feed eaten by the hen 
and the eggs laid. This much we know. At the same 
time no one can say certainly what kind of feed or feeds 
will give the best results in egg yield. Chemistry does 
not tell us. Practical feeders do not tell us. This can 
only be determined by experimental work which will in- 
volve long and careful testing of different feeds and dif- 
ferent rations in actual poultry feeding. We know, how- 
ver, that the egg has a certain combination of elements, 
and we know that to produce eggs the hen must have 
feeds containing certain elements that the egg contains. 
Knowing the composition of eggs, we must study the 
composition of feeds in order to feed intelligently. 
