broad application.

Theine is the one constant agency in the effects of tea. It is
present in teas that are devoid of essential oils--so far as the
senses go--and it then still refreshes, stimulates, sustains,
and even exhilarates, by actual experiment.

The feeling of "comfort," attributed by some writers to the hot
water of the tea, may be also enjoyed by drinking cold tea, which
is no less refreshing in hot weather. The high-flavored essential
oils (strictly oils which evaporate at very moderate
temperatures) of Formosa teas seem to take part in the superior
exhilarating or almost intoxicating effects of the choice
varieties, but we have no certain proof of the fact; while the
more intoxicating and stimulating, as well as deleterious, green
teas possess very little, if any, of these pleasant oils.

It seems to be an authodox opinion among physiologists that tea
contributes nothing towards support of the human system; that it
only rouses it into action, an effect which should, consistently,
be followed by corresponding reaction and depression, which
plainly is not the case. This hypothesis leaves the enquiring
layman in a dilemma. Tea must either enable the system to draw
more heavily or more economically upon the resources afforded by
recognized food, or it is itself nutriment. Otherwise, an
established principle of physics--that there can be no
expenditure of energy without correlative cost--would be
subverted. As tea is admitted upon experience to be most useful,
and most craved by mankind, where the supply of food is
insufficient; and as it is known to refresh and sustain in large