2 
RESEARCHES ON THE MANUFACTURE 
It is, however, very difficult or rather impossible to draw a 
sharp line of demarkation between nutrients or foods and 
stimulants. There is hardly a single article of food which does 
not contain some constituents which excite the organ of taste 
or smell, whilst many of the stimulants contain, in addition to 
their characteristic ingredients, more or less of real nutrients. 
In general, however, these stimulants, when taken moderately, 
either excite the nervous system, make our food palatable, 
stimulate a flagging appetite, or help in digestion. 
Among the numerous stimulants used by mankind, tea is 
one of the most important. It is not only a favourite beverage 
in the East, but is also used as a beverage in the West. It is, 
however, in Japan and China that this kind of beverage is 
popularly used so that there is hardly a single family, however 
poor it may be, not in possession of a set or two of tea drink¬ 
ing utensils. Moreover, along country roads, mountain passes, 
and in public gardens there are tea houses where weary travel¬ 
lers or tired visitors refresh themselves with cups of this 
popular beverage. That tea has become and is becoming a 
favourite beverage of mankind, need, however, excite no sur¬ 
prise, when we consider the effects it produces upon the animal 
system. 
Tea does not essentiably act upon the organ of taste or smell, 
like sugar or vanilla, nor does it, like pepper, excite the stomach 
to an increased secretion of juices, but its chief action is to 
stimulate the central nervous system after it has got into the 
blood. “ It tempers the spirit, and harmonises the mind, drives 
out drowsiness and awakens thought, stops hunger and cures 
repletion, refreshes the body and prevents headache,” these are 
familiar words in praise of the effects of tea, which are, of 
course, somewhat exaggerated. It is, however, true that a cup 
of tea is always refreshing, and there is great ease in working 
after taking tea, but sleeplessness is produced when it is taken 
in great excess. These effects are probably explained by the 
fact that it promotes the circulation of blood in the system. 
Any exertion, either muscular or intellectual, takes place at 
