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The latest analysis of tea is that of Mulder; 
and is as follows :— 
{ 
CHINESE, JAVANESE, 
Hyson, | Congou.} Hyson. | Congou. 
Volatile Oil 0:79 0°60 0:98 0:65 
oe eG : 2:22 1-84 3:24 1:28 
Wax , 0:28 0:00 0:32 0°00 
Resin 2, 3°64 1:64 2°44 
Gum . 8:56 7:28 12 20 11:08 
Tannin . . 17:80 12°83 17:56 14:80 
Theine ‘ ‘ 3 0°43 0:46 0:60 0:65 
Extractive ‘ é 22:80 19°88 21:68 18:64 
Apotheme . — 1:48 — 16+ 
Ext, obtained by hy- 
drochloric acid . 23:60 19:12 20°36 18 24 
Albumen 0 J 3:00 2-80 36+ 1:28 
Fibrous Matter 17:08 28°52 18:20 27-00 
98-78 98:30 | 100 42 97°70 
Salts included in the 
above 5:56 5°24 4°76 5:36 
! 
“ According to this analysis,” remarks Dr. Pe- 
reira, “green tea contains more tannin than 
black tea. This accords with every-day experi- 
ence, as well as with the experiments of Mr. 
Brande; but it is opposed to the results obtained 
by Sir H. Davy and Frank, both of whom state 
that black tea is the most astringent. It is pro- 
| bable, therefore, that the amount of tannin in 
different teas is subject to variation. 
“The substance called theine, or theina, is a 
crystalline salifiable base, discovered some years 
since by Oudry, and since found to be identical 
with caffeine, obtained from coffee. Its formula 
is C; H; N. Oc. It exists in tea in combination 
with tannic acid. Hot water extracts the tan- 
nate of theina as well as free tannic acid; but 
by cooling, both of these substances almost en- 
tirely precipitate. According to Mulder, theina 
is not to be regarded as the principle which con- 
fers on tea its peculiar or characteristic proper- 
ties. Its action on the system is not very obvious. 
He gave half a grain to a rabbit; the animal ate 
but little the next day, and aborted the day after. 
Liebig has suggested that it may contribute to 
the formation of bile. Without entering minute- 
ly into the medicinal action of caffeine (theine) 
he observes, it will surely appear a most striking 
fact, even if we were to deny its influence on the 
process of secretion, that this substance, with the 
addition of oxygen and the elements of water, 
can yield taurine, the nitrogenised compound 
peculiar to bile :— 
latom Caffeine or Theine = = C, 
9 atoms Water 
9 atoms Oxygen ~ 
NEE On 
+6) 2 
9 9 
9 
CAN, Hon, 
OCH IN HE Oe) 
The same authority adds that 2yoths grains of 
caffeine (theine) can give to an ounce of bile the 
nitrogen it contains in the form of taurine. If 
an infusion of tea contain no more than the 7oth 
of a grain of caffeine (theine), still if it contri- 
= 2 atoms Taurine . 
bute in point of fact to the formation of bile, the 
i er 
THA. 
action even of such a quantity cannot be looked | 
upon as a nullity. Neither 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 in the tissues, and 
thus to yield the nitrogenised product which 
enters into the composition of bile, that in such 
a condition the health may be benefitted by the 
use of compounds which are capable of supplying 
the place of the nitrogenised product produced 
in the healthy state of the body, and essential to 
the production of an important element of res- 
piration. In a chemical sense—and it is this 
alone which the preceding remarks are intended 
to show—caffeine or theine, asparagine, and the- 
obromine, are, in virtue of their composition, 
better adapted to this purpose than all other ni- 
trogenised vegetable products. The action of 
these substances, in ordinary circumstances, is 
not obvious; but it unquestionably exists. These 
views, though quite hypothetical, are highly in- 
genious and interesting. 
“The peculiar flavour of tea depends on the 
volatile oil, which is lighter than water, and has 
a lemon-yellow colour, and the taste and smell of 
tea. Alone, it acts as a narcotic ; but in combi- 
nation with tannin, as a diuretic and diaphoretic. 
It is extracted from tea by hot water, in which, 
however, it is not always equally soluble, its | 
solubility being modified by the other consti- 
tuents. 
“The following is the composition of the ashes 
of black tea :— 
| Chinese. 
Javanese, | 
Potash, Sulphate, Fhosphate, and) " : mera 
Muriate of Potash Sh 2:84 3:40 
Oxide of Iron, Car bonate, Sul- | 
phate, and Phosphate of Lime, 1-72 1:64 
and Carbonate of Magnesia 
H per pangatate of Potash . . | Traces — 
Silica . : . : ° 0:68 0:32 
5:24 5 36 | 
| 
“ Notwithstanding the extensive employment 
of tea in this country, it is no easy matter to 
ascertain its precise effects on the constitution. 
Its astringency, proved by its chemical proper- 
ties, depends on the presence of tannin. Of this 
quality we may beneficially avail ourselves in 
some cases of poisoning: as by poisonous mush- 
rooms, by opium or laudanum, or by any other 
vegetable substance containing a vegetable alkali, 
with which the tannin combines. Schwann 
found that tannin throws down a precipitate 
from the artificial digestive liquids, and renders 
this fluid inert. Does the copious use of strong 
tea, therefore, immediately after a meal, impede 
the process of digestion? The peculiar influence 
of tea, especially of the green variety, over the 
nervous system, depends on the volatile oil above 
referred to. This influence is analogous, in some 
respects, to that of foxglove; for both green tea 
and foxglove occasion watchfulness, and act as 
a 
See 
