176 
The American Geologist. 
March, 1896 
There is this distinction between these isotropic substances, 
viz., the glassy grains, as appears in the chondrules of olivine 
where the interlaminations between the lamellae of olivine are 
in part of this glassy substance, on becoming crystalline grad¬ 
ually transmit light and have four extinctions. But the cleav- 
able mineral when perfectly crystalline is continually dark 
between crossed nicols. They, therefore, belong to different 
crystalline systems. 
In a consideration of the specific gravities of the principal 
elements of this meteorite there appears to be reason to look 
for the presence of a lighter mineral than olivine. Thus: 
Specific gravity of olivine... 3.30 
Specific gravity of iron. 7.50 
Specific gravity of the stone. 3.44 
Specific gravity of maskelynite. 2.65 
The small amount of iron present would probably raise the 
specific gravity of the stone higher than 3.44, if not counter¬ 
acted by a lighter mineral. 
The metallic iron is bright and silvery when polished. The 
larger pieces are about 1.5 mm. in diameter, but the smallest 
are mere specks. They are dispersed amongst the other grains 
in a very irregular and fortuitous manner. Some of the finest 
fragments are in the chondrules. 
Troilite is in about the same proportion as metallic iron. It 
has a dark bronzy lustre. 
This meteoric stone, like others that have been described, 
indicates that it came from a source in which heat sufficient 
to cause fusion was a normal condition, that it was disturbed 
in the process of crystallization, or soon subsequent to it, by 
which innumerable fissures were made in the crystalline 
grains, and the separated fragments recompacted, and that 
after complete consolidation a second period of heat was ex¬ 
perienced, a heat, however, which was applied to the external 
surface and was intense enough to momentarily fuse the min¬ 
erals in contact with it, forming the dark glassy crust that 
now covers the mass. That this crust was once in a fused 
condition is indicated by the ridged, wavy contour of the sur¬ 
face, resembling a viscous substance congealed when in a 
greatly disturbed condition. 
The chemical characters and the conclusion as to the min- 
eralogical composition will be given in a later paper. 
Paris , Dec. SI , 1895. 
