136 C. U. Shepard on a Meteoric Stone. 



electricity have had any influence also in producing such an 

 appearance? Tlie fact of the marking however, is most obvious, 

 whatever may have been the cause. 



Viewed near by, the crust is seen to be somewhat variegated 

 in color. Small specks of a yellowish brown, and more rarely, 

 of a yellowish white color, interrupt very frequently the general 

 pitchy hue of the glaze. These lighter colored portions are 

 translucent ; and are seen to arise from the character of the sub- 

 jacent minerals, which have undergone fusion. 



The fresh fracture has an ash-grey color, with a slight inter- 

 mixture of pearl-grey, for the basis of the stone. Three-fifths 

 of the stone 'may be said to have this tint. Diffused through 

 this, occur rounded and polygonal patches (the largest half an 

 inch in diameter, the smallest scarcely distinguishable by the 

 naked eye) of a highly crystalline, snow-white mineral. The 

 former of these minerals, I take to be anorthite, the latter is 

 chladnite. The anorthite is often in four sided, nearly rectangu- 

 lar prismatic crystals, wath blunted edges, and somewhat pitted 

 faces. The largest of these are about one-quarter of an inch in 

 thickness, while the smallest are less than half a rice-grain. 

 Some of them are purplish-grey in color. Yerj distinct crys- 

 talline grains of green pyroxene, nearly a quarter of an inch 

 in diameter are also visible^ here and there, through the stone. 

 They present one very distinct cleavage, like ordinary sahlite. 

 In color, they vary from pistachio-gTcen, to dark blackish grass- 

 green. Olivine in grains of a light-yellowish green color and 

 nearly transparent, is everywhere disseminated through the mass, 

 even tlirougli the white patches of chladnite, w^here however, 

 its color fades to a very 2)ale, wine-yellow tint. The minute 

 black, pitchy crystals were found to exhibit equilateral trian- 

 ;ular faces, and to possess under the blowpipe the characteristic 

 reactions of chromito. They are very numerous; and occur 

 along with exceedingly fine grains of nickeliferous iron, in every 

 portion of the mass. The pyrites, though proved by a treat- 

 ment of the powdered stone with hydrochloric acid, to be 

 present, is nevertheless not to be recognized even with a glass. 

 Among the other constituents of the stone, I noticed a single 

 crystal (apparently dodecahedral) of a hard, red, earthy mineral, 

 closely resembling the substance I called garnet, in the Noble- 

 boro (Maine) meteoric stone. 



The stone breaks with rather more than the usual facility of 



meteoric stones. The specific gravity of fragments =3-23. The 



nickeliferous iron, separated by the magnet, amounted to 2*5 

 p. .c. The stone was then finely powdered ; and on digestion with 

 strong hydrochloric acid, readily suffered decomposition in the 

 feldspathic part of its constitution, with the separation of silicic 



