go ROCHESTER ACADEMY OF SCIENCE. 



The meteorite on reaching Rochester, before cutting, was a 

 semi-circular or ham-shaped mass, lo x 21 x 263^ cm. in its great- 

 est diameters, of which one side (Plate XII, Fig. i) is a comparatively 

 smooth convex surface showing no distinct pittings. The opposite 

 side is much more irregular in form, slightly concave, with three 

 prominent and numerous small characteristic pittings. On the 

 upper edge of this face is a hackly fracture, oblong in shape, 4^^ 

 x 10 cm. in diameter, where a piece, less than a pound according to 

 Prof. Barrows, was broken off by the finder in an effort to discover 

 what made the "stone" so hea\y. The surface of this fracture, 

 like that of the entire mass, being much oxidized, so that the nickel- 

 iferous iron is not visible. On one edge there is a large irregular 

 pitting some 10 cm. long and 5 cm. deep. The whole mass is of a 

 reddish-brown hue, intermingled with large irregular patches of an 

 ochreous-yellow color. On no part of the iron was the true crust 

 observed. Its weight was 43 pounds 11 ounces, or 19.8 kilograms. 



Following the directions of Prof. Ward a few cuts were made 

 parallel to the upper left-hand edge of Plate XII, Fig. i, showing the 

 deep pitting mentioned above, and commencing just within the edge 

 of this pitting. On polishing and etching these cut surfaces, we 

 found that the iron was octahedral in structure, with well marked 

 Widmanstatten figures. A feature of this iron is the fact that it 

 etches so readily that the Widmanstatten figures were slightly out- 

 lined on an ordinary polished surface, without the use of acid or any 

 other solvent. 



The etched surfaces have numerous fissures from }4 to ij4 

 mm. in width and from 5 to 65 mm. in length, partly filled with 

 troilite but mainly with schreibersite. These fissures occur at vari- 

 ous angles toward each other, thus breaking, to some extent, the 

 regularity of the Widmanstatten figures, and are invariably entirely 

 surrounded by kamacite bands. The kamacite bands average from 

 I ^ to 2 mm. in width, with the broadest bands generally surround- 

 ing the schreibersite filled fissures as seen in Plate XII, Fig. 2. The 

 plessite patches which are quite prominent on the etched surfaces 

 show clearly the alternating layers of kamagite and taenite (so-called 

 Laphamite lines), a feature that was first distinguished in another 

 Michigan iron, that of Grand Rapids. On no section were rounded 

 troilite nodules, so characteristic of iron meteorites, found. 



The character of the etched surface of this meteorite in many 

 respects resembles that of Cuernavaca, but the kamacite blades are 



