The openness of the feathers of fowls which do not throw off the water well, like those of most birds, enables them to cleanse themselves easier from insects and dirt, by dusting their feathers, and then shaking off the dirt and these minute pests with the dust. For this purpose one or more ample heaps of sifted ashes, or very dry sand or earth, for them to roll in, must be placed in the sun, and, if possible, under shelter, so as to be warm and perfectly dry. Wood ashes are the best. This dust-heap is as necessary to fowls as water for washing is to human beings. It cleanses their feathers and skin from vermin and impurities, promotes the cuticular or skin excretion, and is materially instrumental in preserving their health. If they should be much troubled with insects, mix in the heap plenty of wood ashes and a little flour of sulphur. A good supply of old mortar-rubbish, or similar substance, must be kept under the shed, or in a dry place, to provide material for the eggshells, or the hens will be liable to lay soft-shelled eggs. Burnt oyster-shells are an excellent substitute for common lime, and should be prepared for use by being heated red-hot, and when cold broken into small pieces with the fingers, but not powdered. Some give chopped or ground bones, or a lump of chalky marl. Eggshells roughly crushed are also good, and are greedily devoured by the hens. A good supply of gravel is also essential, the small stones which the fowls swallow being necessary to enable them to digest their hard food. Fowls swallow all grain whole, their bills not being adapted for crushing it like the teeth of the rabbit or the horse, and it is prepared for digestion by the action of a strong and muscular gizzard, lined with a tough leathery membrane, which forms a remarkable peculiarity in the internal structure of fowls and turkeys. "By the action," says Mr. W. H. L. Martin, "of the two thick muscular sides of this gizzard on each other, the seeds and grains swallowed (and previously macerated in the crop, and there softened by a peculiar secretion oozing from glandular pores) are ground up, or triturated in order that their due digestion may take place. It is a remarkable fact that these birds are in the habit of swallowing small pebbles, bits of gravel, and similar substances, which it would seem are essential to their health. The definite use of these substances, which are certainly ground down by the mill-like action of the gizzard, has been a matter of difference among various physiologists, and many experiments, with a view to elucidate the subject, have been undertaken. It was sufficiently proved by Spallanzani that the digestive fluid was incapable of dissolving grains of barley, &c., in their unbruised state; and this he ascertained by filling small hollow and perforated balls and tubes of metal or glass with grain, and causing them to be swallowed by turkeys and other fowls; when examined, after twenty-four and forty-eight hours,