contained in the food.

In these days of fraud and adulteration, nearly all the cheaper grades
of tinware contain a greater or less amount of lead in their
composition, which owing to its greater abundance and less price, is
used as an adulterant of tin. Lead is also used in the solder with which
the parts of tinware are united. The action of acids upon lead form very
poisonous compounds, and all lead-adulterated utensils should be wholly
discarded for cooking purposes.

_Test for Lead-Adulterated Tin._--Place upon the metal a small drop of
nitric acid, spreading it to the size of a dime, dry with gentle heat,
apply a drop of water, then add a small crystal of iodide of potash. If
lead is present, a yellowish color will be seen very soon after the
addition of the iodide. Lead glazing, which is frequently employed on
crockery and ironware in the manufacture of cooking utensils, may also
be detected in the same manner.

Cooking utensils made of copper are not to be recommended from the point
of healthfulness, although many cooks esteem them because copper is a
better conductor of heat than iron or tin. The acids of many fruits
combine with copper to form extremely poisonous substances. Fatty
substances, as well as salt and sugar, act upon copper to a greater or
less degree, also vegetables containing sulfur in their composition and
produce harmful compounds.

Utensils made of brass, which is a compound of copper and zinc, are not
safe to use for cooking purposes.