THE ability to candle accurately is becoming of in- 
creasing importance to all who are engaged in the 
production, transportation, and sale of eggs. Buyers 
are gradually adopting the practice of purchasing eggs 
on a graded basis as an effective means of reducing the 
large losses from bad eggs. For the successful opera- 
tion of such a system a knowledge of candling is indis- 
pensable. Furthermore, only by candling can a ship- 
per make certain that his eggs comply with Federal, 
State, and municipal regulations. 
Eggs are graded for market according to their fresh- 
ness, cleanliness, size, color, and soundness of shell. 
Freshness, an egg's most important quality, and sound- 
ness of shell can be judged best by candling in a dark 
room. All that is needed is a bright light surrounded 
by a shield with a small opening before which the egg 
is held. A kerosene lamp and a piece of stovepipe 
will suffice for the small candler, but for those who 
handle large numbers of eggs more elaborate appa- 
ratus may prove necessary. Two different kinds of 
egg-candling devices are illustrated in this bulletin. 
The candler must be thoroughly familiar with the 
structure of the egg. He must know how to hold an 
egg when candling it. Most important of all, he needs 
io become acquainted with the principal distinguishing 
characteristics of each kind of egg found in commerce 
before he will be able to determine accurately whether 
a given egg should be graded as marketable or unmar- 
ketable. The purpose of this bulletin is to furnish the 
information required. The candler himself will have 
to supply the experience. 
Sometimes an egg is so near the border line that it 
is hard to know whether to class it as good or bad. 
When there is any doubt as to its fitness for food pur- 
poses, the candler should reject the egg as inedible; 
that is, he should give the consumer the benefit of the 
doubt. 
