18 BULLETIN 471, U. S. DEPARTMENT OF AGRICULTURE. 
eggs long distances and keep them for fairly long periods in good 
condition. 
When the housewife depends upon eggs from her own hens, or 
even when she or the grocer buys direct from a local producer, she 
can expect to get eggs less than a week old. and the term " fresh-laid 
eggs'- has some meaning. When, however, she buys them in city 
markets, especially during the autumn and winter months when hens 
are not laying freely, the chances are that all except a very few high- 
priced eggs purchased from some local producer were laid at least 
several weeks before and very likely hundreds of miles away. This 
does not means that city-market eggs are necessarily bad eggs. On 
the contrary, when handled by good methods, they may be better in 
quality than fresh local eggs that have been improperly cared for. 
The housekeeper's problem in selecting eggs is complicated by the 
fact that it is hard to tell the quality of an egg from its appearance. 
There is undoubtedly a quality in the absolutely fresh, clean egg 
which is not found in any other and which will last only a day or two 
under the best of conditions and can not always be secured even in 
new-laid eggs. This change or loss of quality depends quite as much 
on the character and cleanliness of the egg and the conditions under 
which it is held as on the length of time it is kept. Since examination 
is now almost a necessity in the trade, and the importance of reliable 
standards of excellence is being recognized the housekeeper should 
be familiar with the commercial methods. 
The main points by which an expert judges the quality of an egg 
are size, shape, soundness and cleanliness of the shell, and appearance 
of the interior when candled (held against an opening which permits 
light to shine through the egg). When an egg is newly laid, its con- 
tents seem to fill the shell, as it is seen against the candle, but very 
soon an air space begins to appear in one end and gradually increases 
in size until it may fill even half the shell. This shrinking is due to 
the evaporation of water through the porous shell, and as it increases 
the weight of the egg decreases. Hence, the old household floating 
test for eggs — fresh ones sink when put into a pail of water, while 
old ones float. When a fresh egg is candled the yolk is barely dis- 
tinguishable from the white, save as a slightly darker area in the 
center of the egg. In older eggs the yolk looks darker and often shifts 
its place in the egg. Various kinds of dark spots and blotches may 
also develop, due to different causes, but all indicating a spoiling egg. 
When all of the egg meat looks dark in candling the egg is rotten. 
The art of candling is easily learned and often practiced by house- 
keepers. 
The housekeeper can buy more intelligently if she knows how eggs 
are graded in the trade and that prices vary accordingly. The grades 
are commonly designated: "First quality" — large, fresh eggs with 
