Chemistry and Physics. 403 
Potash felspar, 3 var. | Chlorite, 2 var. Brown garnet. 
Soda felspar. Tale, 2 var. Dolomite 
Lithia felspar. Serpentine. Flint glass. 
Glassy felspar. Steatite. Green bottle glass. 
Labradorite. Olivine. reen German glass. 
Mica, 2 var. Hypersthene. Hard white Bohemia 
seucite. glass. 
Analcime. | Hornblende, 2 var. Wedgewood mortar. 
Mesoty pe. Actinolite. hinese porcelain. 
Scolecite, Tremolite. 
Schorl j i Anthracite. 
Greenstone, 2 var. Asbestus, 2 var. Bituminous coal. 
Chalcedony. Coccolite. Lignite. 
Obsidian. . Charcoal. 
Epidote massive. Ashes of coal and 
Gneiss. Epidote crystals,2 var.| wood. 
Hornblende slate, &c. | Axinite. Woods. 
Soils, Prehnite. 
(1.) By the tache process we find that all the minerals and glasses in 
this list are partially decomposed and dissolved by carbonated water, 
and most of them also by pure water. © eds 
When the substance is very minutely powdered, before mingling it 
with the liquid, even the first drops that pass the filter will commoaly 
give a tache containing some of the alkali or alkaline earth that has 
been dissolved. In this way proof of the solvent power of the car- 
the result is much feebler, and requires a longer time. But with nearly 
all the substances enumerated, it is entirely unequivocal, and with some 
of them quite intense. 
by the volume and whiteness of the tache. But further and more mi- 
hute information is obtained by testing the tache before ignition, and 
hection with test paper, in examining the tache, so as to recognize the 
alkalies and alkaline earths severally present in the tache of felspar, 
ornblende, serpentine, epidote, and other mine 
These a 
