Evans Austin, _Factory Acts_).

_Bread Sluffs._--As compared with wheat-flour, all other materials used
for making bread are of secondary importance. Rye bread is largely
consumed in some of the northern parts of Europe, and cakes of maize
meal are eaten in the United States. In southern Europe the meal of
various species of millet is used, and in India and China durra and
other cereal grains are baked for food. Of non-cereal flour, the
principal used for bread-making is buckwheat (_Fagopyrum esculentum_),
extensively employed in Russia, Holland and the United States. The flour
of pease, beans and other leguminous seeds is also baked into cakes, and
in South America the meal of the tapioca plant, _Jatropha Manihot_, is
employed. But, excepting rye, none of these substances is used for
making vesiculated or fermented bread.

Quality of flour.

A normal sample of wheat-flour consists roughly of 10 parts of moisture,
72 of starch, 14 of nitrogenous matter, 2.25 of fatty matters, and 1.75%
of mineral matter. Starch is thus the predominating component; it is
not, however, the dough-forming ingredient. By itself, starch, when
saturated with water, forms a putty-like mass devoid of coherence, and
it is the gluten of the nitrogenous matter which is the binding
constituent in dough-making, because when wetted it forms a more or less
elastic body. The proportion of gluten in wheat-flour varies from 7 to
15%, but the mere quantity of gluten is by no means the only standard of
the commercial value of the flour, the quality also counting for much.
One of the functions of gluten is to produce a high or well-piled loaf,
and its value for this purpose depends largely on its quality. This is
turn depends largely on the variety of wheat; certain races of wheat are
much richer in nitrogenous elements than others, but such wheats
usually only flourish in certain countries. Soil and climate are
undoubtedly factors in modifying the character of wheat, and necessarily
therefore of the flour. The same wheat grown in the same soil will show
very varying degrees of strength (i.e. of gluten) in different seasons.
For instance, the north-western districts of America grow a hard spring
wheat which in a normal season is of almost unequalled strength. In 1904
an excess of moisture and deficiency in sun in the Red River Valley
during the critical months of June and July caused a serious attack of
red and black rust in these wheat fields, the d