a 
ers = 
7, 
eee 
and the Products of its Transmutation. 139 
specimens of decomposed Wernerite, potash was found to pre- 
dominate over the soda. 
The composition of the red Wernerite is further remarkable 
from the presence of a larger quantity of magnesia than has 
yet been met with in these minerals. This earth undoubtedly 
plays a very important part in the transmutation of minerals, 
as is sufficiently evidenced by the great varieties of pseudo- 
morphous steatite, talc, and chlorite, together with the fact 
that bicarbonate of magnesia and silicate of lime undergo a 
mutual interchange of constituents. Rose found that a 
number of altered augites (salite) always shewed an increase 
in the proportions of silica and magnesia, bagetnor with a de- 
erease of lime. 
B. SUBSTITUTION OF MAGNESIA FOR ALKALIES. 
Black Scapolite from Arendal. 
The crystals were very soft and without any trace of 
cleavage. Density, 2837. Analysis gave— 
a. fi ie IYI. 
Silica, ; ‘ 29-52 — 29°52 
Alumina, . : 15°41 16:13 15°77 
Peroxide of iron, . 19°25 19-03 19°14 
Lime, : F 8-94 9-10 9-02 
Magnesia, . ; — 8°50 8°50 
Potash, : : — 0:37 0°37 
Soda, : — 0:58 0-58 
Water and paitilen’ 10-89 10°89 10-89 
Carbonate of lime, 4:62 4:62 4°62 
98°45 
The quantities of oxygen being— 
Silica, F : 15°32 4 
Alumina, . . 7:37 
Peroxide of iron, . rat Behe hes 
Lime, ‘ , 2°56 
Magnesia, . ; 3°42 it 
~ ee  d  Ce o 
Soda, ‘ , 0:15 
Water, ‘ ’ ! , 9:68 2°52 
In the composition of this mineral the proportion between 
the bases RO and R, O,, is not essentially different from that 
found in the unaltered mineral; the percentage of silica is, 
however, very much lower than in any other instance, so that 
