THE METEOEIC PERIDOTITES.— TUFA. 105 



L' Aigle, Onic, France. 



This possesses a gray grouiKliuass, holding chondri. One of the chondri shows a 

 concave depression, the same as those described by Tschermak as occurring iu the 

 Tieschitz meteorite. (See ante, page 101.) 



Weston, Connecticut. 



This shows the same gray groundmass as the preceding, and an excellently developed 

 chondritic structure. 



Chatemi Rennrcl, France. 



This has a light-gray groundmass, sprinkled with metallic points. 



Hessle, Sweden. 

 This has a grayish chondritic groundmass. 



Noblcboro , Ilaine. 



This specimen is apparently fragmental in character, and closely resembles a trachytic 

 or rhyolitic ash. The specific gravity, according to "Webster, is 2.08, but, according to 

 Kumler, 3.092. It is probable that Webster's chemical analysis is not correct, the speci- 

 men, if authentic, not bearing out any such analysis as that published by him.* 



This meteorite ought to be reexamined chemically, and studied microscopically. 



Variety. — Tufa. 



Orvinio, Ilahj. 



The structure of the Orvinio meteorite is described \y\ Tschermak as uncommon and 

 remarkable. The rock is composed of clear-colored fragments, surrounded by a compact, 

 dark, cementing mass. 



The fragments are yellowish-gray, and contain spherules and particles of iron and 

 pyrrhotite. The cementing material is blackish, compact, and splintry, holding nearly 

 uniformly-distributed particles ; and near its contact with the fragments shows an 

 evident fluidal structure. This makes it in the highest degree probable that the cement- 

 ing material was once in a plastic condition and in motion. The fragments are darker, 

 harder, and more brittle at the junction with the inclosing mass than they are in the 

 middle. From this it would seem that the matrix had been at a very high temperature 

 when plastic. 



The fragments and matrix both have almost the same composition, density, and 

 mineral characters. 



This meteorite resembles a volcanic rock in which a fine matrix holds fragments of 

 rock of the same character. The structure is the same as it is when a younger compact 

 lava breaks through an older and more crystalline one. 



The fragments have the usual chondritic structure. They contain, besides iron and 

 pp'rhotite, olivine, bronzite (enstatite), and possibly some feldspar. For the further 



* Bost. Jour. Phil., 182i, i. 3S6-3S9 ; Bucliuer, Meteoriteu iu Samuilungcu, ]S63, p. -tG. 



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