Prof. Silliman’s Description of the Maryland Aérolite. 109 
did in the aérolites of Jonzac (Journ. de Phys. tome xcii. p. 136), 
appearances of crystallization; although it is possible there may 
have been an incipient process of that kind, especially as the 
small parts are translucent*. The Maryland stone is highl 
magnetic; pieces as large as peas are readily lifted by the 
magnet, and that instrument takes up a large proportion of 
the smaller fragments. ‘The iron is metallic and perfectly 
malleable ; although none of the pieces are larger than a pin’s 
head, still they are readily extended by the hammer. The 
iron in the crust is glazed over, so that the eye does not per- 
ceive its metallic character; but the file instantly brightens 
the innumerable points which then break through the varnish 
of the crust, and give it a brilliant metallic lustre, at all the 
points where the file has uncovered the iron. The same is the 
fact with the Weston stone, and with that of L’Aigle, but not 
with that of Stannern in Moravia; specimens of allof which, and 
of the meteoric iron of Pallas, of Louisiana, and of Auvergne, 
are now before me. The aérolites of Jonzac and of Stannern, 
as stated by M. Bellevue, are the only ones hitherto discovered 
that do not contain native iron, and do not affect the magnet ; 
still their analysis presents a good deal of iron, which is pro- 
bably in the condition of oxide. 
- The iron in the metallic state is very conspicuous in the 
Weston stone, sometimes in pieces of two inches in length ; 
and both in this stone and in that of Maryland it is often 
brilliant like the fracture of the meteoric iron of Pallas and-of 
Louisiana. 
In the analysis of the Weston stone published in 1808, I 
did not discover chrome, although it was afterwards announced 
by Mr. Warden. I have desired Mr. Chilton to re-analyse 
the Weston stone, and he has nearly completed the labour, 
the result of which may be given hereafter; but he writes that 
he has not been able to discover any chrome. I am not quite 
sure that I discover pyrites in the Maryland aérolite, although 
it is mentioned by Dr. Carver in his letter in the preceding 
volume. 
October 4, 1825. 
* This vitreous appearance I believe has not been observed before (at 
Jeast as far as appears in any account that I have seen). It seems to have 
resulted from intense heat; the same, doubtless, which covered the exterior 
with the black crust ; and the difference of the two is probably to be as- 
cribed to the one being covered and compressed, and to the other being on 
the outside. 
XVIII. Essay 
