20 B. Silliman—Meteoric Iron from California. 
as will be observed, by reference to the accompanying analysis, 
is more than twice the average amount of that metal found in 
other meteoric irons. 
The crystalline structure of this mass is obscure. The Wid- 
mannstittian figures are not developed on it by etching, although 
a confused granular structure was evident after this process. 
Wishing to test this point thoroughly, I consulted Mr. John E. 
Gavit, of the American Bank Note Company, in New York, who 
is well known for his microscopic and other scientific tastes. 
Mr. Gavit very kindly tried all the resources known to the en- 
pier art with a view to develop, by etching this iron, a sur- 
ce from which its curious cryptocerystalline structure could 
be transferred to Ste printing. All these attempts have 
exhibited. 
An attempt to develop this eryptocrystalline structure by 
the aid of a fine “tint,” laid on an etching ground by a ruling 
machine and bitten in; and also by a medallion ruled in ortho- 
graphic projection, upon which the crystalline lines, it was 
hoped, might appear in symmetrical form, was not more suc- 
cessful than the other trials. Thus it appears practically hope- 
less to transfer to paper, by printing, a structure which may 
yet be clearly seen by the lens. 
The suggestion, made long since by Berzelius, that the Wid- 
mannstiittian figures were due to the segregation of the nickel 
alloy, in lines of the octahedron, which the etching developed, 
owing to the inferior solubility of the alloy as compared with 
the pure iron, seems to meet no support from this mass, in which 
the uncommonly high percentage of nicke! would naturally lead 
us to expect a proportionate clear development of the er stal- 
line structure. Is it not rather the probable solution of this 
structure that it is due to the length of time during which the 
meteoric mass is kept at a high temperature, while slowly cool- 
ing.? Under such conditions, the molecules can — 
themselves in symmetrical forms, and over broad surfaces. 1n 
the mass before us, it would appear from what has been said of 
the crust, that the heat did not penetrate to a greater depth 
below the surface than 4 or 5 millimeters. 
e Cape of Good Hope iron analyzed by Uricochoea re- 
sembles this both in the absence of Widmannstittian figures, 
and in its high proportion of nickel; but its cobalt is much 
