136 Analysts of the Maryland Aerolite. 
This circumstance is much less apparent upon the erolites 
of Weston (1807,) L’aigle (1803) and Stannern in Moravia 
(1808) : it appears to have arisen from the rapid cooling of 
the external vitreous crust after intense ignition. It is im- 
possible to doubt that this crust is a result of great and sud- 
den heat. In the Maryland erolite it is not quite so thick as 
the back of a common penknife, and, as in that of Weston 
and Stannern, it is separated by a well defined line, from 
the mass of the stone beneath. The mass of the stone is, 
on the fractured surface, of a light ash gray colour, or per- 
haps more properly of a grayish white; it is very uniform 
in its appearance, and not marked by that strong contrast 
of dark and light gray spots, which is so conspicuous in the 
Weston meteorolite. The fractured surface of the Mary- 
Jand stone is uneven and granular, harsh and dry to the 
touch, and it scratches window glass decidedly, but not with 
great energy. To the naked eye it presents very small glisten- 
ing metallic points, and a few minute globular or ovoidal bodies 
scattered here and there, through the mass of the stone. 
With a magnifier all these appearances are of course much 
increased. The adhesion of the small parts of the stone is 
so feeble, that it falls to pieces with a slight blow, and exhib- 
its an appearance almost like grains of sand. The metallic 
parts are conspicuous, but they are much less numerous than 
the earthy portions, which, when separated, are nearly white, 
and have a pretty high vitreous lustre, considerably resem- 
bling porcelain. They appear as if they had undergone an 
incipient vitrification, and as if they had been feebly aggluti- 
nated by a very intense heat. I cannot say that I observed 
in them asM. Fleuriau de Bellevue did in the erolites of Jon- 
zac (Jour. de Phys. tome 92, pa. 136) appearances of crystal- 
ization, although it is possible there may have been an incip- 
ient process of that kind, especially as the small parts are 
translucent.* The Maryland stone is highly magnetic ; pieces 
as large as peas are readily lifted by the magnet, and that 
instrument takes up a large proportion of the smaller frag- 
* This vitreous appearance I believe has not been observed before (at 
least as far as appears in any account that I have seen.) It seems to 
have resulted from intense heat; the some doubtless, which covered 
the exterior, with the black crust, and the difference of the two is prob- 
ably to be ascribed to the one being covered and compressed, ard to the 
other being on the outside. 
