harmful. Good
potatoes should have a smooth skin and few eyes; the flesh pale and of
a uniform color and of a firm consistency. A rough skin, with little
depressions, indicates a disease called "scab"; dark-brown patches on
the skin are due to a disease called "smut." Potatoes with such
diseases are of inferior quality. If green on one side, due to
exposure to the sun when growing, the potatoes are unwholesome.

=Fruits.=--Underripe or green fruit should never be eaten. This
condition may be easily detected by the color and consistency of the
fruit. Diseased or decayed fruit is known by its change of color,
softening, and external mold. Spots on fruit are often caused by a
fungus which lowers its quality and renders it less wholesome.

=CEREALS AND THEIR PRODUCTS--Cereals.=--Particularly when bought in
original packages cereals are generally pure and unadulterated. When
bought in bulk there may be found dust, dirt, worms, insects, and
excessive moisture. These may all be determined by careful inspection.
The presence of an undue amount of moisture adds greatly to the weight
of cereals and is therefore a fraud. Cereals should be dry to the
touch and the individual kernels or particles separate and distinct.

=Flour.=--By this general term is meant the ordinary wheat flour. It
should not be too moist, should have a fine white appearance, remain
lumpy, or hold its form, on pressure, not show any particles which
cannot be crushed, and when a handful is thrown against the wall, part
of it should adhere. The odor and taste should be fresh and clean and
not musty or moldy.

The common adulterants are corn and rice meal. If a sample of the
flour be thrown on the surface of a glassful of water, the corn and
rice, being heavier, will sink; grit and sand may be detected in the
same way. If the flour has been adulterated with mineral substances it
may be shown by burning a portion down to an ash; the ash of pure
flour should not exceed two per cent of the total amount; if mineral
substances are present the amount of ash will be greatly increased.

Alum is sometimes added to flour in order to give it a whiter
appearance and to produce whiter and lighter bread; it is most
unwholesome. It can be detected by the so-called "logwood" test, which
is prepared and used as follows:

Make two solutions. The first: a five per cent solution of logwood
chips in alcohol. The second: a fifteen per cent solution of ammonium
carbonate in wa