On no account select eggs about the freshness of which there is any reason to doubt.  The use of stale eggs may result in serious disturbances of the digestive organs.

An English gentleman who has investigated the subject quite thoroughly, finds upon careful microscopical examination that stale eggs often contain cells of a peculiar fungoid growth, which seems to have developed from that portion of the egg which would have furnished material for the flesh and bones of the chick had the process of development been continued.  Experiments with such eggs upon dogs produce poisonous effects.

There are several ways of determining with tolerable accuracy respecting the freshness of an egg.  A common test is to place it between the eye and a strong light.  If fresh, the white will appear translucent, and the outline of the yolk can be distinctly traced.  By keeping, eggs become cloudy, and when decidedly stale, a distinct, dark, cloud-like appearance may be discerned opposite some portion of the shell.  Another test is to shake the egg gently at the ear; if a gurgle or thud is heard, the egg is bad.  Again, eggs may be tested by dropping into a vessel containing a solution of salt and water, in the proportion of a tablespoonful to a quart.  Newly laid eggs will sink; if more than six days old, they will float in the liquid; if bad, they will be so light as to ride on the surface of the brine.  The shell of a freshly laid egg is almost full; but owing to the porous character of the shell, with age and exposure to air a portion of the liquid substance of which the egg is composed evaporates, and air accumulates in its place at one of the extremities of the shell.  Hence an egg loses in density from day to day, and the longer the egg has been kept, the lighter it becomes, and the higher it will rise in the liquid.

An egg that will float on the surface of the liquid is of too questionable a character to be used without breaking, and is apt to be unfit for use at all.

HOW TO KEEP EGGS.—­To preserve the interior of an egg in its natural state, it is necessary to seal the pores of the shell air-tight, as the air which finds its way into the egg through the pores of the shell causes gradual decomposition.  Various methods are devised to exclude the air and thus preserve the egg.  A good way is to dip perfectly fresh eggs into a thick solution of gum-arabic,—­equal parts of gum and water,—­let the eggs dry and dip them again, taking care that the shells are entirely covered with the solution each time.  When dry, wrap separately in paper and pack in a box of sawdust, bran, salt, or powdered charcoal, and cover tightly to keep out the air.

There is a difference of opinion as to which end should be placed down in packing; most authorities recommend the smaller end.  However, an experienced poultryman offers the following reasons for packing with the larger end down:  “The air-chamber is in the larger end, and if that is placed down, the yolk will not break through and touch the shell and thereby spoil.  Another thing:  if the air-chamber is down, the egg is not so liable to shrink away.”