needed; if this is done, there need be little fear of their impurity,
for whole spices are difficult to simulate or adulterate. Ground
spices may be adulterated with bark, flour, starches, or arrowroot;
these adulterants are harmless, but are fraudulent, as they increase
the bulk and decrease the strength. Their actual presences can only be
demonstrated by a microscopical or chemical examination.

=Peppers.=--Black pepper is made from the whole berry; white pepper is
made from the same berry with the outer husk removed. The adulterants
are usually inert and harmless substances, such as flour, mustard, or
linseed oil; their presence is obviated by the use of the whole
peppercorns, ground as needed.

=Red Pepper.=--This may be adulterated with red lead; when pure it
will be entirely suspended in water; if a sediment falls it is
probably red lead.

=Mustard.=--Practically all of the adulterants of mustard can only be
detected by intricate chemical tests. The presence of turmeric may be
detected by the appearance of an orange-red color when ammonia is
added to a solution of the sample.

=Tomato Catsup.=--Artificial dyestuffs are common, giving a brilliant
crimson or magenta color. Such catsup does not resemble the natural
dull red or brown color of the homemade article.

Preservatives, such as boric, salicylic, or benzoic acids and their
salts, are sometimes added. While their presence cannot be condoned,
yet they are usually present in small amounts and therefore
practically harmless.

=Pickles.=--These should be of a dull-green color. The bright emerald
green sometimes observed is due to the presence of the salts of
copper; this may be proved by dipping the blade of a penknife in the
liquor, as described under the heading of "Canned Goods."

Alum is sometimes used as a preservative and in order to make the
pickles crisp. Its presence may be demonstrated by means of the
"logwood" test mentioned under the heading of "Flour."

=VINEGAR.=--Cider vinegar is of a brownish-yellow color and possesses
a strong odor of apples.

Wine vinegar is light yellow if made from white wine, and red if made
from red wine.

Malt vinegar is brown and has an odor suggestive of sour beer.

Glucose vinegar has the taste and odor of fermented sugar.

Molasses vinegar has the distinctive odor and taste of molasses.

=OLIVE OIL.=--Pure olive oil has a pleasant, bland taste and a
distinctive and agreeable odor, unmistakable in ch