Bread made from milk, is, of course, richer and more nutritious than that made from water and bread made from potato water contains more starch; both of these retain their moisture longer than bread made with water. Mould, which sometimes forms upon bread, is, like the yeast, a minute plant. It is floating about everywhere in the air, ready to settle down wherever it finds a suitable home. Moisture and heat favor its growth, hence bread should be thoroughly cooled before it is put into a jar or bread box and the bread box should be kept in a cool place. _Rye bread_ contains a little more starch and less protein than wheat bread. It contains more water and holds its moisture longer. _Biscuits._ The objection to eating hot bread, does not hold for baking powder or soda biscuits, if well cooked, because these cool more rapidly and they do not contain the yeast plant; hence, they do not ferment as does the bread. Baking powder is made from bicarbonate of soda (baking soda) and cream of tartar. When these are brought in contact with moisture, carbon dioxid is formed, and, in the effort to escape, it causes the dough to expand and become light. The reason that the cook attempts to bake her biscuits, or anything made with baking powder as quickly as possible, after the baking powder comes in contact with the moisture, is that the dough may have the full effect of the expansion of the gas. If the room in which she mixes her dough is cool, or if her biscuit dough is left in a cool place, this is not important, as heat and moisture are both required for full combustion. _Macaroni and spaghetti_ are made from a special wheat flour rich in gluten known as Durum. They contain about seventy-seven per cent starch, little fat and little protein. They may take the place of bread, rice or potato at a meal. * * * * * =Rice= is a staple cereal in all tropical and temperate climates. It requires special machinery to remove the husk and the dark, outer skin of the kernel. It is seldom eaten within three months after harvesting and it is considered even better after two or three years. It requires thorough cooking. Unhusked rice is called paddy. _Wild rice_ is used by the North American Indians. The seeds are longer, thinner and darker, than the tame rice. It is coming into favor as a side dish, but it is served more particularly at hotels in soup and with game. As previously stated, rice contains a larger proportion of starch than any other cereal and the smallest proportion of protein. Next to rice, in starches, comes wheat flour; yet whole wheat or graham flour contain half as much again of protein.