88 PERIDOTITE. 



the grains would have united from the crystallization of the base, and a three-twinned 

 rounded crystal resulted. The remaining portion of the figure is composed of hase, 

 olivine, enstatite, chondri, u'on, pyrrhotite, and, possibly, magnetite. 



Figure 5, on the same plate, shows one of tlie large chondri composed of olivine and 

 enstatite, which blends at the lower portion of the figure with the general groundmass, 

 showing that they are only somewhat differently differentiated portions of the con- 

 tinuous mass. The grams are surrounded by a gray base, while the yellowish and red- 

 dish-brown tints represent the staining from the oxidation of the iron. In figure 4 the 

 base is darker than represented, and in figure 5 lighter. The colors of the two should be 

 exchanged. 



Dhunnsalu, Punjab, India. 



This meteorite is described by Professor A. von Lasaulx as having a light-gray 

 groundmass, sprinkled with yellowish rusty spots. Microscopically, it was seen to 

 possess a chondritic structure, similar to the meteorite from Iowa County. The chon- 

 dri are composed of olivine and enstatite, with the fibrous cementing material. Besides 

 olivine and enstatite the rock contains iron and troilite, as well as chromite or mag- 

 netite.* 



Kni/aJdiuja, Ilvngarij. 



The Knyahinya meteorite was examined microscopically by Professor Adolf Kenn- 

 gott in 1869. His section was of a gray color spotted with yellow, semi-transparent, but 

 containing opaque and dark-yellow spots. The whole appears finely grained to the 

 unaided vision, but spheroidally grained under a low magnifying power. The granules 

 are gray, and some of them more or less angular. Besides the metallic and opaque par- 

 ticles two crystalline minerals were seen. One is colorless and transparent, the other 

 gray and translucent. Some of the spherules consist essentially of one or the other of 

 these minerals. The opaque substances are subordinate, and are interposed between the 

 rounded or angular granules. Kenngott regards this spherulitic structure as the result of 

 a process of crystallization within the substance of the meteorite, and not from an aggre- 

 gation of separately formed bodies. 



The opaque substances are light-gray metallic iron, grayish-yellow pyrrhotite, and a 

 black material. In reflected light the iron appears dark-gray and translucent, the pyr- 

 rhotite blackish-yellow and faintly diaphanous, and the black substance opaque. The 

 silicates are regarded as enstatite and olivine. 



Descriptions of the granules (chondri) were given by Professor Kenngott. One is 

 said to possess a striped appearance, owing to alternations of a delicate transparent sub- 

 stance with a gray one. The bands are partly parallel and partly divergent. When 

 the power is 900 the structure is resolved into a mere aggregation of gray and hyaline 

 particles. The gray mineral (enstatite) constitutes essentially many of the round or 

 rounded granules, while other granules are formed from a union of the olivine and 

 enstatite. The two silicates crystallized simultaneously, one or the other of them, accord- 

 ing to circumstances, having accumulated around certain centres in a spherical form, tluis 

 imparting to the meteorite as a whole a somewhat oiilitic aspect. The original paper is 

 illustrated by drawings of the granules.^ 



* Sitz. iiiedcr. GescUs. Bomi, 1SS2, pp. 105-107. 



t Sitz. Wieu. Akad., ISGO, lix. (2), 873-SSO ; Phil. Mag., 1869 (1), x.^cxviii. 424-428. 



