CONSTITUENTS OF TEAS. 887 
probably very rarely present, would be very objectionable even in very 
small quantities. Sulphate of iron is a powerful astringent. In the 
small quantities which would be used in increasing the astringency of 
teas it would possibly not be seriously objectionable. It may also be 
said of sulphate of iron that this substance was not detected in a very 
large number of samples examined by Hassall nor in the Department’s 
samples. 
Facing, if excessive, increases the weight of the tea, but there is no 
evidence of its being prejudicial to the health. 
From these statements we see that the adulterations of teas are in- 
tended more especially to enhance the value of inferior grades, except 
in the case of lie tea or the addition of foreign or exhausted leaves. In 
the latter eases a spurious article, which is not justified by any quality 
or principle which it contains, is foisted upon the market. 
The evidence of authorities upon food adulteration confirms the state- 
ment that the addition of foreign leaves is now but little practiced. 
The general freedom of the teas of the markets of the United States 
from adulteration is largely due to the enforcement of the United States 
tea-adulteration law. Dr. Jesse P. Battershall,' under whose direc- 
tion a very large number of samples of teas were examined in con- 
nection with this law, notes a very perceptible improvement in the 
quality of teas imported under its provisions. 
GENERAL STATEMENTS CONCERNING THE CONSTITUENTS OF TEAS. 
The analyses of teas give little or no evidence bearing upon the mar- 
ket value of this commodity. A tea may be very rich in theine or tan- 
nin, and yet bring the same price as one poor in these substances. The 
same may be said in a general way of the other constituents. This is 
largely due, undoubtedly, to differences in soil, climate, the age of the 
leat, and methods of manufacture. The flavor, strength, and appear- 
ance of a tea in general determine its market value. The flavor is due 
to the volatile oil developed during the manufacture, the strength to 
the proportion of tannin, and the appearance of the leaf to its age and 
the care taken in the rolling and other manipulations. A tea may be 
deficient in tannin and still bring a high price on account of the delicacy 
of its flavor, or, by the admixture of leaves rich in tannin, an operation 
termed blending, its strength may be increased to meet the demands 
of the market. In genuine unfaced teas the value is usually in a direct 
ratio with the soluble matter in the ash. According to Geisler, the 
finer the quality of the tea the more theine, soluble ash, and extractive 
matter it will contain, though this is not uniformly true. It has been 
stated that the relatively high price of Indian teas is largely due to 
their percentage of tannin. This permits the use of a very much smaller 
quantity of tea in preparing the infusion for the table. The writer found, 
‘Food Adulteration and Its Detection, E. & F.Spou, New York, p. 20. 
