When the shells of the eggs are somewhat soft, it is because the hens are rather inclined to grow too fat. It is then proper to mix up a little chalk in their water, and to put a little mortar rubbish in their food, the quantity of which should be diminished. We give the following remarks by an experienced poultry-keeper of the old school, as valuable from being the result of practice: "The hen sometimes experiences a difficulty in laying. In this case a few grains of salt or garlic put into the vent have been successfully tried. The keeper should indeed make use of the latter mode to find out the place where a hen has laid without his knowledge; for, as the hen will be in haste to deposit her egg, her pace towards the nest will be quickened; she may then be followed and her secret found out." "Though one particular form," says Mr. Dickson, "is so common to eggs, that it is known by the familiar name of egg-shaped, yet all keepers of poultry must be aware that eggs are sometimes nearly round, and sometimes almost cylindrical, besides innumerable minor shades of difference. In fact, eggs differ so much in shape, that it is said experienced poultry-keepers can tell by the shape of the eggs alone the hen that laid them; for, strange to say, however different in size the eggs of any particular hen may be occasionally, they are very rarely different in form. Among the most remarkable eggs may be mentioned those of the Shanghae, or Cochin-China fowl, which are of a pale chocolate colour; and those of the Dorking fowl, which are of a pure white, and nearly as round as balls. The eggs of the Malay fowls are brown; those of the Polish fowl, which are very much pointed at one end, are of a delicate pinkish white; and those of the Bantam are of a long oval." A very important part of the egg is the air-bag, or _folliculus aeris_, which is placed at the larger end, between the shell and its lining membranes. It is, according to Dr. Paris, about the size of the eye of a small bird in new laid eggs, but enlarges to ten times that size during the process of incubation. "This air-bag," says Mr. Dickson, "is of such great importance to the development of the chick, probably by supplying it with a limited atmosphere of oxygen, that if the blunt end of the egg be pierced with the point of the smallest needle (a stratagem which malice not unfrequently suggests), the egg cannot be hatched, but perishes."