BRISTOL NATURALISTS' SOCIETY, 
From the '■'■Bristol Daily PosV oj Nov. 9. 
Notwithstanding the unfavourable state of the weather 
last Thursday evening, there was a good attendance at the 
I usual monthly meeting of this society, at the Philosophical 
' Institution ; and we were much pleased to see several lady 
visitors, in accordance with the recently-altered regulations 
of the society. 
After the transaction of some routine business, and the 
election of four new members, the president, Mr. W. Sanders, 
announced that an attack of illness prevented Mr. Hugh 
Owen from reading his promised paper, and he therefore 
called upon Mr. W. W. Stoddart for his paper on "Tea and 
its Adulterations." 
At the commencement, Mr. Stoddart said that he wished 
thus publicly to contradict an assertion that he, in a recent 
lecture, had accused the grocers of Bristol of adulterating 
their tea. The fact was, as he would soon show, that he had 
had very great difficulty in getting adulterated samples ; at 
all the respectable grocers', and many of the minor shops, 
where he bad obtained samples, he invariably found genuine 
tea sold. The tea-plant, the author stated, belonged to the 
same natural order as the camellias, and there was very good 
reason to believe that all the teas of commerce were obtained 
I from varieties of one and the same species of plant. The 
! seed was sown in March, transplanted in a year, and the 
plants placed in rows, three or four feet apart, and kept down 
to a height of three feet by cutting off the top shoot. Leaves 
were gathered from a plant between the ages of five and 
twelve years. There v ere three gatherings in a year; the 
first in May, which yielded white woolly twigs, whence the 
name Pekoe. The tea cultivation in China extended over 
3| millions of acres, with an average yearly produce of a 
million tons, of whith Great Britain consumed about one 
forty-fifth part. Mr. Stoddart then explained that green 
and black tea were made from the same leaves — those for 
green tea being gathered and dried as quickly as possible; 
those for black being much exposed to air, &c., before drying, 
I which favoured the production of a peculiar oil, to which 
black tea owed its peculiar properties. By distilling 
black tea with water, this oil could be obtained in a 
pure state, and was found to be very intoxicating : a 
hundredweight of tea would yield a pound of this 
oil. A very important constituent of the tea - leaf was 
the alkaloid theine, found also in the coffee plant and 
1 others. The proportion by w eight w as two per cent. It was 
' a white crystalline substance, with no smell, and a slightly 
bitter taste— there was less of it in black than in green tea. 
Chemically, this substance much resembled one of the con- 
stituents of the bile, and, like it, would, under certain con- 
ditions, give rise to a most brilliant purple dye. Tannic acid 
(found la) gely in oak bark) existed in tea to the extent of one- 
; fourth their weight. Boiling water dissolved 40 per cent, 
of the leaves, extracting the oil, the theine, and the tannic 
acid. What remained behind was the most nutritious of all, 
viz., the gluten, the presence of which in flour, peas, beans, 
&c., gave such foods their flet^h-forming power ; the addition 
of soda to the infusion caused more of this gluten to be dis- 
solved, and therefore the tea was more nutritious, but the 
constant employment of an alkali was deleterious to health. 
The " steppe water " from which the Tartars made their tea 
was highly alkaline, hence their tea was much more sustain- 
ing. The alkaloid theine acted upon the body in a very re- 
markable, and hitherto unexplained, manner; viz., it pre- 
vented the wasting away of the muscular and other tissues — 
and therefore, though it did not actually nourish, it was a 
vtry good preservative of the flesh— hence the well-known 
fact that poor people who unhappily were stinted in their 
food consumed so much tea. Too much tea, it was well 
known, acted hurtfully on the system, but the mode was un- 
j explained as yet. Mr. Stoddart then proceeded to speak of 
