QUALITY IN EGGS 
(5) Chicks visible to the candle. 
The loss due to heated eggs is enormous; probably greater 
than that caused by any other source of loss to the egg trade. 
The loss varies with the season of the year, and the climate. 
In New England heat loss is to be considered as in the same 
class as loss from dirties and checks. In Texas the egg busi- 
ness from the 15th of June until cool weather in the fall is 
practically dead. People stop eating eggs at home and 
shipping out of the State nets the producer such small returns 
by the time the loss is allowed that, at the prices offered, it 
hardly pays the farmer to gather the eggs. In the season of 
1901 hatched chickens were commonly found in cases of mar- 
ket eggs, throughout the trans-Mississippi region, and eggs did 
well to net the shippers three cents per dozen. 
Damage to eggs by heating and consequent financial loss is 
inexcusable. In the first place, market eggs have no business 
being fertilized, but whether they are or not they should be 
kept in a place sufficiently cool to prevent all germ growth. 
The egg shell is porous so that the developing chick may 
obtain air. This exposes the moist contents of the egg to the 
drying influence of the atmosphere. Evaporation from eggs 
takes place constantly. It is increased by warm temperatures, 
dry air and currents of air striking the egg. 
When the egg is formed within the hen the contents fill the 
shell completely. As the egg cools the contents shrink, and 
the two layers of membrane separate in the large end of the 
egg, causing the appearance of the bubble or air cell. Evapor- 
ation of water from the egg further shrinks the contents and 
increases the size of the air cell. The size of the air cell is 
commonly taken as a guide to the age of the egg. But when 
we consider that with the same relative humidity on a hot 
July day, evaporation would take place about ten times as 
fast as on a frosty November morning, and that differences in 
humidity and air currents equally great occur between locali- 
ties, we see that the age of an egg, judged by this method, 
means simply the extent of evaporation, and proves nothing 
at all about the actual age. 
Hven as a measure of evaporation, the size of the air cell 
may be deceptive, for when an egg with an air cell of consid- 
erable size is roughly handled, the air cell breaks down the 
side of the egg, and gives the air cell the appearance of being 
larger than it really is. Still rougher handling of shrunken 
eggs may cause the rupture of the inner membrane, allowing 
the air to escape into the contents of the egg. This causes 
a so-called watery or frothy egg. The quality is in no wise 
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