B. Silliman—Meteoric Iron from California. 19 
exhibited with this communication) shows a cross section meas- 
uring 12X18 centimeters. The section is approximately a 
semicircle, having the flattened side for its diameter, with the 
outline and exterior coating perfectly preserved on all sides. 
Its weight was over 800 grams. The largest dimensions of the 
entire mass were about 24 and 29 centimeters. 
This meteoric mass is remarkably homogeneous in structure: 
and singularly free from included minerals. Only two very 
small masses of pyrites, of 3 and 5 millimeters diameter, are visi- 
ble on one side of the slab, and exteriorly I could detect no 
heterogeneous substance. When the surfaces of the section 
exhibited were reduced in the planing machine, it was observe 
that the exterior or crust was so much harder than the general 
peaches of the section as to cause the tool to rise a little, thus 
“aving a distinct margin slightly elevated above the adjacent 
Parts, and of a whiter color. This hardened crust had a depth 
of four to five millimeters, 
The density of this iron, determined on a mass of over 750 
Ens in weight, is 7:875, while the density of the shavings cut 
sana € planing tool from the same mass is 8024, showing a 
(of Sasa of 0149 by this mechanical process. This density 
ito © Mass) is above the average specific gravity of meteoric 
My OWlng probably to its large percentage of nickel, which, 
