Wheat bread is now common in most countries. The best and whitest is made from the flour of the first grinding. _Gluten_ is a very important part of flour, and it is that which gives wheat the superiority over all other grains, it being found only in small quantities in any other. It is the gluten which helps to form the adhesive paste essential to secure fermentation. It is common in the animal kingdom, but rare in the vegetable, and therefore is sometimes called the _vegeto-animal principle_. The more gluten the better and more nutritious the flour. The loss of this principle, by sprouting, mildew, etc., destroys the adhesive power so necessary to making good bread. The best qualities of flour take up the largest quantity of moisture; the amount which can be absorbed depends on the quantity of gluten. In dry weather, flour requires more moisture than in wet, and long and faithful kneading will add to the power of absorption, without making the bread too thin. Common salt and alum are often used to give poor flour the tenderness and whiteness of good brands. A little salt is good, but too much is injurious, both to the bread and to the health,--alum still more injurious. Liebig recommends lime-water in bread-making. A quarter of a pound of slacked lime to a gallon of pure rain or distilled water, kept in closely stopped bottles; two and a half pints of the lime-water to nine pounds of flour, he says, will make a sweet, fine-grained, elastic bread of exquisite flavor. The lime-water to be mixed with the flour before the yeast is added. Of course, it will not be enough moisture for that amount of flour, and as much more water is added as is needed. Liebig claims that the lime will give the wheat a larger amount of bone-making element, and therefore be more nutritious. Rice flour, or potatoes combined with flour, help to take up moisture, and keep bread from drying. Rye flour makes a dark-colored bread, but is sweet and palatable, retaining moisture longer than wheat. Indian meal, mixed with rye, and a spoonful or two of molasses added with the yeast, makes the New England brown bread; but to have that in perfection it should be baked in a brick oven, and remain all night; then, warm and fresh for breakfast, it is unrivalled.