\ 
126 EXPLOITATION OF PLANTS 
2. In any one class of tea, the higher priced sorts con- 
tain more caffeine and tannin than the cheaper sorts. 
3. Taking two teas of a single class, one smooth and 
pleasant to the taste, and expensive; the other harsh 
and astringent, and cheap: then the former tea has its 
tannin and caffeine in balanced combination with little 
or no surplus of free tannin ; while the cheaper tea has 
a relatively much larger surplus of uncombined tannin, 
resulting in the harsh astringency characteristic of its 
class. This is well seen in the Indian and Ceylon 
teas; with China teas it is noticeable that, so far 
as the above analyses indicate, they seldom give any 
free tannin ; but, per contra, usually-possess a relatively 
higher percentage of uncombined caffeine, which fact 
probably accounts for the pleasant bitterness of many 
China sorts. There would appear to be evidence for 
supposing that in China teas the caffeine has relation- 
ship with some constituent other than tannin. 
Summing up: as regards Indian and Ceylon teas, 
at any rate, it seems that in good quality, high-priced 
sorts, there is comparatively little uncombined tannin ; 
in low priced sorts, a notable surplus. On the 
other hand, most good teas contain caffeine in some 
excess. Further, teas of higher value contain more 
total caffeine and tannin (i. e. beverage making material) 
than cheap teas, and in practice actually may prove to 
be more economical, as well as more wholesome than 
cheap teas. 
TEA MANUFACTURE 
We may now refer to the processes of manufacture 
which result in these interesting complications. The 
