4th. _Fat-forming Food._--Consisting of fatty or oily substances; these occur, to a considerable extent, in Indian corn (the yellow variety), oatmeal, middlings, bran, &c. All experiments that have been made tend to prove that each of these kinds of food is unable to serve the purposes of the others; thus, to give an example, neither warmth-giving nor fat-forming substances are capable of adding to the flesh of a growing animal, nor can flesh-forming food increase the quantity of fat. In a mere elementary work, like the present, it is impossible to go into this subject at any great length. Those who desire the facts on which these statements are grounded are referred to the works of Johnston, Liebig, and other eminent agriculturists and agricultural chemists. We must take the principles as granted, and apply them to an examination of the different substances usually employed in poultry feeding. GRAIN forms the staple food of poultry, the varieties used being generally either barley, oats, wheat, Indian corn, or rice. _Barley_ is perhaps more frequently used than any other grain; it is better relished by fowls than oats, and its first cost is considerably below that of wheat. It contains from ten to eleven pounds of flesh-forming, sixty of starchy substances, and two to three of oil or fat in every hundred. _Oats_ are not taken so freely as barley, which is apparently owing to the large proportion of husk they contain, which lessens their value as poultry food; but when used in the form of grits or oatmeal they are eaten with great avidity, and in this state furnish one of the most wholesome and nutritious varieties of food, containing eighteen of flesh-forming, sixty-three of starchy substances, and six pounds of fatty materials in every hundred. No grain contains a larger proportion of flesh-forming substances than oatmeal--it is, therefore, the one best adapted to growing animals, and I have found that chicken make much more rapid progress when it forms the chief portion of their food than when fed on any other substances. Cochin, and Spanish chicken especially, show its good effects by the rapidity with which they feather when fed with it. _Wheat_, contrary to the popular opinion, is not more nutritious than oatmeal; it contains about twelve pounds of flesh-forming nutriment, seventy of starchy, and two to four of oil, in every hundred. Its cost operates considerably against its employment, although it is extensively used by some breeders of choice poultry, with whom expense of feeding is a secondary consideration.