erted into sugar. Hence old wheat and beans contain more
starch than new; and in our stomachs other vegetable and animal materials
are converted into sugar; which constitutes in all creatures a part of
their chyle.

Hence it is probable, that sugar is the most nutritive part of vegetables;
and that they are more nutritive, as they are convertible in greater
quantity into sugar by the power of digestion; as appears from sugar being
found in the chyle of all animals, and from its existing in great quantity
in the urine of patients in the diabaetes, of which a curious case is
related in Sect. XXIX. 4. where a man labouring under this malady eat and
drank an enormous quantity, and sometimes voided sixteen pints of water in
a day, with an ounce of sugar in each pint.

2. Oil, when mixed with mucilage or coagulable lymph, as in cream or new
milk, is easy of digestion, and constitutes probably the most nutritive
part of animal diet; as oil is another part of the chyle of all animals. As
these two materials, sugar and butter, contain much nutriment under a small
volume, and readily undergo some chemical change so as to become acid or
rancid; they are liable to disturb weak stomachs, when taken in large
quantity, more than aliment, which contains less nourishment, and is at the
same time less liable to chemical changes; because the chyle is produced
quicker than the torpid lacteals can absorb it, and thence undergoes a
further chemical process. Sugar and butter therefore are not so easily
digested, when taken in large quantity, as those things, which contain less
nutriment; hence, where the stomach is weak, they must be used in less
quantity. But the custom of some people in restraining children entirely
from them, is depriving them of a very wholesome, agreeable, and
substantial part of their diet. Honey, manna, sap-juice, are different
kinds of less pure sugar.

3. All the esculent vegetables contain a bland oil, or mucilage, or starch,
or sugar, or acid; and, as their stimulus is moderate, are properly given
alone as food in inflammatory diseases; and mixed with milk constitute the
food of thousands. Other vegetables possess various degrees and various
kinds of stimulus; and to these we are beholden for the greater part of our
Materia Medica, which produce nausea, sickness, vomiting, catharsis,
intoxication, inflammation, and even death, if unskilfully administered.

The acrid or intoxicating, and other kinds of vegetable j