The experiments and observations hitherto related render it
evident, that Tea possesses a fragrant volatile principle, which in
general tends to relax and enfeeble the system of delicate persons,
particularly when it is drank hot, and in large quantities. I have
known many of this frame of constitution, who have been persuaded,
on account of their health, to deny themselves this fashionable
infusion, and received great benefit (SECT. VII.). Others, who have
found their health impaired by this indulgence, are unhappily induced
to continue it for want of an agreeable substitute, especially for
breakfast.
But, if such cannot wholly omit this favourite regale, they may
certainly take it with more safety, by boiling the Tea a few minutes,
in order to dissipate this fragrant principle (SECT. II. 1, and EXP.
IV.) which is the most noxious; and extract the bitter, astringent,
and most stomachic part (SECT. II. 2, and EXP. III.) instead of
preparing it in the usual manner by infusion.
An eminent physician in the city, frequently experiencing the
prejudicial effects of Tea by drinking it in the usual form, was
induced, from reading a dissertation upon this subject, published
some time since at Leyden[93], to try the infusion prepared after
another manner. He ordered the Tea to be infused in hot water, which
after a few hours he caused to be poured off, stand over night, and
to be made warm again in the morning for breakfast. By this means,
he assures me, he can take, without inconvenience, near double the
quantity of Tea, which formerly, when prepared in the usual method,
produced many disagreeable nervous complaints.
The same end is obtained by substituting the extract of Tea (SECT.
II. 2.) instead of the leaves. It may be used in the form of Tea, by
dissolving it in warm water; and, as the fragrancy of the Tea is in
this case dissipated, the nervous relaxing effects, which follow the
drinking it in the usual manner, would be in great measure avoided.
This extract has been imported into Europe from China, in flat round
dark-coloured cakes, not exceeding a quarter of an ounce each in
weight, ten grains of which, dissolved in a sufficient quantity of
water, might suffice one person for breakfast. It might also be made
here without much expence or trouble (See SECT. II. 2.).
It is remarkable, that in all the forms which Du Halde relates, for
administering Tea as a stomachic medicine among the Chinese, it is
ordered to be boiled for some time, or prepared in such a manner,
as to cause a dissipation of its fragrant perishable flavour; which
practice, as it seems consonant to experiments here (SECT. II.
EXP. III.), may probably have taken its rise in China, from long
experience and repeated facts.