FEB., 19006. THE SoutH BEND METEORITE. 21 
to be 3.35 and that of nickel-iron to be 7.70, the ratio of chrysolite 
to nickel-iron by weight in the meteorite indicated by this specific 
gravity is:— 
eh at Mins Wace bare tl aay sah ciothny tos 4 thse pe x ois 78.63 
RMB EIT) Soe MRM cee GN a der riiiy, Boone 6 Pode Phos al oh doe hw) Sas ny 21.27 

I00.00 
This result is necessarily too high for the chrysolite and too low 
for the nickel-iron as regards the original constitution of the mass, 
on account of the fact that some of the original nickel-iron has 
altered to limonite, and some of the pores contain more or less sand. 
What change should be made in the above figures on this account 
in order to express the actual original composition of the meteorite, 
however, it is impossible to determine, but it is hardly likely that 
a change greater than 5 % should be made. 
_A piece of the meteorite weighing about 220 grams was removed 
by sawing, giving a section having a surface about 2 inches square 
available for study. The appearance of this section is shown in 
Plate XVII. As indicated by the external characters, the interior of 
the mass proves to be a sponge-like body of nickel-iron, the pores 
of which are filled with chrysolite. The shape of the pores tends 
to be rounded or polygonal, but is occasionally elongated or quite 
irregular. A diameter of about half an inch (12 mm.) is a common 
one for the pores, and they rarely exceed this. The distribution of 
the nickel-iron is rather uniformly tenuous but occasionally bunched 
so as to give a square centimeter of surface without chrysolite. 
The walls of the pores as seen after removal of the chrysolite are 
sinuous rather than angular and have smooth surfaces. A black 
graphitic layer about .1 mm. in thickness usually lines the pores, 
separating the nickel-iron from the chrysolite. A similar layer 
occurring in the Mount Vernon meteorite has been described by 
Tassin.* Etching brings out well-defined figures on the nickel-iron 
showing that it is made-up of the usual alloys of kamacite, tenite and 
plessite. The kamacite bands are swollen and very variable in width, 
but rarely exceed 2mm.inthisdirection. For the most part the bands 
tend to border the chrysolite blebs, following their outlines in vary- 
ing course. Bordering the kamacite on the side opposite the chry- 
solite occurs a thin ribbon of tenite appearing and disappearing 
without regularity, but for the most part quite constant. The 
plessite, dark gray in color, fills the spaces between the kamacite 
bands, resembling in its irregular shapes the hieroglyphic figures 
assumed by schreibersite in some of the ataxites. At times its 
* Proc. U.S. Nat. Museum, 1005, vol. xxxiii, p. 216. 
