590 Dr. Walter Flight — History of Meteorites. 



tion; it weighs 293-3 kilog. (5 cwt. 3 qrs. 3 lbs.), and measures 2ft. 

 4 in. long and 18 in. broad, and penetrated the ground to a depth of 

 11 ft. For drawings of this enormous block, the largest mass of 

 meteoric rock preserved in any collection, and coloured representa- 

 tions of the meteor which was observed at the time of its descent, 

 the reader is referred to von Haidinger's two memoirs. 



Kenngott has published the results of a microscopic investigation 

 of thin sections of a fragment of this meteorite, illustrated with 

 eight drawings indicating peculiarities of structure. To the naked 

 eye the section appears to be finely granular and of a grey tint, and 

 even with a very moderate power is seen to present spberular 

 structure, recalling, if relative size be left out of consideration, that 

 of the globular diorite of Corsica. The opaque ingredients are 

 nickel-iron, troilite, and a black substance ; in addition to these 

 are two crystalline mineral species, the one colourless and trans- 

 parent and somewhat fissured, the other grey and translucent and 

 presenting an appearance of lamellar structure ; both appear in 

 angular and rounded granules, and both are bi-refractive ; they are 

 differently affected by hydrochloric acid, and from other differences 

 in their crystalline characters it may be inferred that the grey 

 silicate is enstatite, the colourless silicate is peridot. It is hardly 

 possible to give the reader in a small compass an idea of Kenngott's 

 detailed description of the various granules ; the grey mineral he 

 observed to constitute several of the round or rounded granules, and 

 in most of the specimens there was clear evidence that the two 

 silicates had crystallized simultaneously; in one instance an alter- 

 nation of the two minerals in one and the same granule, as it occurs 

 in globular diorite, is remarked, the interior consisting of the 

 grey mineral, finely striated and surrounded with black opaque 

 substance, around which again is a granular aggregation of the 

 transparent fissured silicate, locally interspersed with particles of 

 the black opaque substance and of nickel-iron. 



Fragments heated before the blowpipe become covered with a 

 black enamel, while the grey powder of the meteorite, when 

 moistened with distilled water, reacts distinctly, sometimes in- 

 tensely, on turmeric paper. The specific gravity of this stone is 

 3 515. 



It was not until a lapse of six years from the date of this very 

 abundant aerolitic fall that a specimen was submitted to careful 

 chemical analysis. Von Baumhauer, by whom it was undertaken, 

 finds the Knyahinya meteorite to have the following composition : — 



Nickel-iron 



50 



Troilite 



2-2 



Chromite 



08 



Olivine 



39-9 



Insoluble silicate 



52-1 



100-0 

 The nickel-iron contains : 



Iron = 79-94 ; Nickel = 20-06. Total = 100-00 



