r gum, and mineral matter. This
toughness and elasticity of gluten is an important quality; for in
bread-making, were it not for the gluten, the carbonic-acid gas formed by
the action of yeast on dough would all escape. But, though it works its
way out vigorously enough to swell up each cell, the gluten binds it fast,
and enables us to have a panful of light "sponge," where a few hours
before was only a third of a pan.

Starch, as you have seen, will not dissolve in the cold water. Dry it,
after the water is poured on, and minute grains remain. Look at these
grains under a microscope, and each one is cased in a thick skin, which
cold water can not dissolve. In boiling water, the skins crack, and the
inside swells and becomes gummy. Long boiling is thus an essential for all
starchy foods.

Bread proper is simply flour, water, and salt, mixed to a firm dough and
baked. Such bread as this, Abram gave to his angelic guests, and at this
day the Bedouin Arab bakes it on his heated stone. But bread, as we
understand it, is always lightened by the addition of yeast or some form
of baking-powder, yeast making the most wholesome as well as most
palatable bread. Carbonic-acid gas is the active agent required; and yeast
so acts upon the little starch-granules, which the microscope shows as
forming the finest flour, that this gas is formed and evenly distributed
through the whole dough. The process is slow, and in the action some of
the natural sweetness of the flour is lost. In what is known as aerated
bread, the gas made was forced directly into the dough, by means of a
machine invented for the purpose; and a very scientific and very good
bread it is. But it demands an apparatus not to be had save at great
expense, and the older fashions give a sufficiently sweet and desirable
bread.

_Rye_ and _Indian Corn_ form the next best-known varieties of flour in
bread-making; but barley and oats are also used, and beans, pease, rice,
chestnuts, in short, any farinaceous seed, or legume rich in starch, can
fill the office.

_Oatmeal_ may take rank as one of the best and most digestible forms of
farinaceous food. Some twenty-eight per cent of the grain is husk,
seventy-two being kernel; and this kernel forms a meal containing twelve
parts of nitrogenous matter, sixty-three of carbo-hydrates, five and a
half of fatty matter, three of saline, and fifteen of water. So little
gluten is found, that the flour of oats can not be made into loav