19-1 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xxiv. 
Montgomery, and Marion, the latter place lieing about 16 miles west 
of Augustin. 
So far as can be learned — a part of the information being obtained 
by Mr. Coleman from negroes — the stone at the time of the explosion 
broke into thi-ee pieces, the larger of which AYas the one brought to 
Mr. Sturdevant and which is said to have originally weighed about 7 
pounds, as already noted. Another small piece was found, but has 
disappeared, and the third, if such there was, was never found. The 
stone, as obtained by Mr. Coleman, was broken into five pieces which 
weighed altogether 2,049 grams. As shown in the illustration (Plate 
XIII), it was about 13 centimeters in its greatest length, by 9 in l)readth, 
and about the same thickness, and was covered except where broken, 
by a very thin black crust, nowhere more than half a millimeter in 
thickness. The color on the broken surfaces is dark smoky gray, 
almost black. It is very fine grained, with numerous small dark 
chondrules, not more than 1 to 2 millimeters in diameter at most, 
and with no metallic iron visible to the naked eye. The mass is quite 
soft and friable and resembles in a general way the stones of Warrenton, 
Warren County, Missouri, and Lance, France, more closely than those 
of any other locality with which the author is acquainted. 
The color is, however, darker than is the Warren Countj^ stone, and 
the chondritic structure more pronounced than in that of Lance. It is, 
moreover, uniformly gray in color, and not speckled with white, as is 
the last named. Under the microscope the stone is seen at once to 
belong to the chondritic t^q^e, as is indeed evident on close inspection 
by the naked eye. The essential minerals are olivine, augite, and 
enstatite, with troilite and native iron, the silicates occurring in the 
form of chondrules, or associated more or less f ragmental particles, 
embedded in a dark, opaque, or faintl}^ translucent base, which is irre- 
solvable so far as the microscope is concerned. The structure is 
pronouncedly fragmental and the stone belongs, beyond question, to 
the group of tuffs. 
The details of the microscopic structure are as follows: In a very 
dense, dark gray, seemingly amorphous base are scattered various 
silicate minerals in the form of fragments and chondrules, and inter- 
spersed with occasional minute blebs of native iron and troilite. The 
chondrules are composed of olivine, enstatite, or augite, and are some- 
times monosomatic and sometimes polysomatic, holocr3"stalline, or 
with a varying amount of glassj^ base. Interspersed with these are 
fragments of olivines and enstatites of all sizes, from a half a milli- 
meter down to the finest dust. Scattered through the ground mass are 
proportionalh' large plates or clusters of enstatites, as shown in Plate 
XIV, fig. 1. These are verj^ light gray in color, with poorly defined 
outlines and extreme^ irregular borders projecting into the black 
