146 Carbonate of Lime.— Analysis of Tea. 
CARBONATE OF LIME. 
Mr. Dalton, in a paper on the analysis of spring and mineral 
waters, states, ‘‘ that all spring water containing carbonate or 
super-carbonate of lime is essentially limy or alkaline, by the 
colour tests, And this alkalinity is not destroyed till some more 
powerful acid, such as the sulphuric or muriatic, is added, suffi- 
cient to saturate the whole of the lime. Indeed, these acids may 
be considered as sutficient for tests of the quantity of lime in such 
waters ; and nothing more is required than to mark the quantity 
of acid necessary to neutralize the lime. It does not signify whe- 
ther the water is boiled or unboiled, nor whether it contains sul- 
phate of lime along with the carbonate; it is still limy in propor- 
tion to the quantity of carbonate of lime it contains. Agreeably 
to this idea, too, I find that the metallic oxides, as those of iron 
or copper, are thrown down by common spring water, just the 
same as by free lime. Notwithstanding, this carbonate of lime, 
in solution in water, contains twice the acid that chalk or lime- 
stone does. 1 fully expected the super-carbonate of lime in so- 
lution to be acid; but it is strongly alkaline, and scarcely any 
quantity of carbonic acid water put to it, will overcome this al- 
kalinity. Pure carbonic acid water is, however, acid to the tests. 
I could not be convinced of the remarkable fact stated in this pa- 
ragraph, till I actually formed super-carbonate of lime, by super- 
saturating lime water in the usual way, till the liquid from heing 
milky became clear. It still continued limy, and was even doubt- 
fully so when two or three times the quantity of acid was added, 
It should seem, then, to be as impossible to obtain a neutral car- 
bonate of lime, as it is to obtain a neutral carbonate of ammo- 
nia, in the sense here attached to the word neutral.’’—Memoirs 
of the Manchester Society. 
ANALYSIS OF TEA. 
In the 24th number of the Quarterly Journal of Science, Mr. 
Brande has published analyses of black and of green tea, from 
which he finds that “ the quantity of astringent matter precipi- 
table by gelatine is somewhat greater in green than in black tea, 
though the excess is by uo means so great as the comparative 
flavours of the two would lead one to expect. It also appears 
that the entire quantity of soluble matter is greater in green than 
in black tea, and that the proportion of extractive matter not 
precipitable by gelatine is greatest in the latter.” 
*¢ Sulphuric, muriatic, and acetic acids, but especially the first, 
oceasion precipitates in infusions both of black and green tea, 
which have the properties of combinations of those acids with 
tan. Both infusions also yield, as might be expected, abundant 
black pregipitates, with solutions of iron; and when mixed with 
acetate, 
