can it be denied, that in the case of an
excess of non-azotised food, and a deficiency of motion, which is
required to cause the change of matter of the tissues, and thus to
yield the nitrogenised product which enters into the composition of
the bile, that in such a condition the health may be benefited by the
use of compounds which are capable of supplying the place of the
nitrogenised substances produced in the healthy state of the body, and
essential to the production of an important element of inspiration. In
a chronical sense, and it is this alone which the preceding remarks
are intended to show, caffeine, or theine, &c., are, in virtue of
their composition, better adapted to this purpose than all
nitrogenised vegetable principles. The action of these substances in
ordinary circumstances is not obvious, but it unquestionably exists.
Tea and coffee were originally met with among nations whose diet was
chiefly vegetable.

Considerable discussion has taken place regarding the tea plants; some
say that there is only one species; others that there are two or
three. Mr. Fortune, who visited the tea districts of Canton, Fokien,
and Chekiang, asserts that the black and green teas of the northern
districts of China are obtained from the same species or variety,
known under the name of _Thea Bohea_. Some make the Assam tea a
different species, and thus recognise three: _T. Cantoniensis_ or
_Bohea_, _T. Viridis_, and _T. Assamica_. The quality of the tea
depends much on the season when the leaves are picked, the mode in
which it is prepared, as well as the district in which it grows. The
green teas include Twankay, Young Hyson, Hyson, Gunpowder, and
Imperial; while the black comprise Bohea, Congou, Souchong, Oolong,
and Pekoe. The teas of certain districts, such as Anhoi, have peculiar
characters.

The first tea imported into England was a package of two pounds, by
the East India Company, in 1664, as a present to the king; in 1667,
another small importation took place, from the company's factory at
Bantam. The directors ordered their servants to "send home by their
ships 100 pounds weight of the best _tey_ they could get." In 1678
were imported 4,713 lbs.; but in the six following years the entire
imports amounted to no more than 410 lbs. According to Milburn's
"Oriental Commerce," the consumption in 1711 was 141,995 lbs.; 120,595
lbs. in 1715, and 237,904 lbs. in 1720. In 1745 the amount was 730,729
lbs. For above a centu