192 Dr. Thomson’s Notice of some new Minerals. 
Its constitution may be represented by the formula 
14 (Mg S) + 3($/+ 4A4l) S? +11 Aq. 
Asbestus contains more silica and a good deal.of lime, which 
is wanting in baltimorite: asbestus, in fact, is merely a variety 
of pyroxene. 
7. For the next mineral, which from its constitution I call 
subsesquisulphate of alumina, 1am also indebted to Mr. Alger. 
The locality is South Peru. 
It is a soft, opake mineral, composed of silky fibres adhering 
to each other. ‘The colour is white, but there is a reddish 
yellow tint which partially pervades the specimens, owing ob- 
viously to a little foreign matter with which they are stained. 
The taste is acid and sweet, like that of alum. The specific 
gravity is 1:584. It is soluble in water. The constituents are 
Sulphuric acid ..... 32:95 
PASIAB aa a cats i bn tory Len 
Sulphate of soda .... 6°50 
Veer Sain 'e cite) ences). 29D 
Obviously, 1 atom ofsulphuric acid ... 5° 
11. atom of alumina. +... «|<, 3°875 
1 atom of sulphate of soda .. 9°0 
5 atoms of water ....... 5625 
23° 
The sulphate of soda exists in a greater proportion than 
sulphate of potash or of ammonia does in our alum, It is 
curious that in South America soda almost universally re- 
places the potash which occurs in other parts of the world. 
Instead of saltpetre, so abundant in India and even in Europe, 
we have nitrate of soda in Peru, and instead of potash alum, 
we find in Buenos Ayres and other districts of South America, 
soda alum deposited in amygdaloidal cavities in a kind of shale. 
8. Messrs. Alger and Jackson gave the name of Acadio- 
lite to a variety of chabasite which they found in Nova Scotia, 
and specimens of which Mr. Alger was kind enough to send 
tome. The colour of the mineral is yellow, and it has the 
crystalline shape and the characters of chabasite so completely, 
that it would be considered as a mere variety of that mineral 
were it not that the constituents do not quite agree. The spe- 
cific gravity of acadiolite is 20202, and its constituents, 
Be a el et ae 
Altmina ..... © oe Lemaire 
EG ats. ESS SG 
Peroxide of iron. .... 24 
WHEE Te 2 2 0s ono eG 
