Feb., 1906. The Shelburne Meteorite. ii 



together in the manner indicated in Plates IX and X is a somewhat 

 conchoidal one, indicating a scaling off from a larger mass. Such 

 a form, as is well known, is exhibited by other meteorites, notably 

 that of Butsura among stones and Canon Diablo among iron mete- 

 orites. Such a form would be especially liable to fracture during 

 descent. Borgstrom remarks that the larger stone is characterized 

 by concave surfaces. This is also true of the smaller one, and of 

 Butsura as well. The two parts when placed together in the manner 

 indicated in Plates IX and X correspond perfectly as regards front 

 and rear sides. The rear side of each is concave, smooth, and has 

 broad, shallow pits. The front side is concave, rough, and has small, 

 deep pits. 



The pittings of the two surfaces of the smaller stone shown in 

 Plates V and VII differ in character from those of the other surfaces. 

 These surfaces may be said to be rougher than the others in the 

 sense that the roughness is due to a greater abundance and smaller 

 size of the pittings. The shape of the pittings is irregular, but in 

 general, saucer-like with diameters of .5 to 1 centimeter. On the 

 face shown in Plate VII the pittings tend to become elongated in 

 character, with the long axes parallel with the long direction of 

 the surface. The edges which both these rough surfaces make 

 where they join the other surfaces of the meteorite are much sharper 

 than the edges of other parts of the meteorite. These sharper edges 

 and roughness indicate less exposure to fusion and erosion, and 

 therefore a mid-atmospheric fracture along these surfaces. The 

 largest pits on the meteorite are on the surfaces shown in Plate 

 VIII. One depression here shows an area of about 3x3 cm. and a 

 depth of 1 cm. Secondary pits break the configuration of this, but 

 all have sloping, rounded edges, showing fusion and erosion during 

 the entire aerial passage of the meteorite. The depressions on the 

 rear side, that shown in Plate VI, are still broader and shallower in 

 character and blend in with the general surface so as to nearly lose 

 the character of pits. 



The crust of the meteorite is uniformly black in color. While 

 in general smooth in appearance, it is seen even with the naked eye 

 to be dotted over with minute grains rising above the general surface. 

 These are for the most part protruding metallic grains whose bright 

 surface can be discovered by filing. Besides these the crust may 

 be seen under a lens to be abundantly stippled with clots and threads 

 which anastomose and blend with one another, producing hollows 

 and elevations. The threads rarely extend more than a few milli- 



