Dr. Walter Flight — History of Meteorites. 555 



only slightly affected by atmospheric agency, freshly cut surfaces 

 retaining their brightness perfectly. The specific gravity of the 

 iron is 7-821 and the composition : 



Iron = 87-02; Nickel = 12-29; Cobalt = 0-65; Phosphorus = 0-02; Copper =trace. 



Total = 99-98. 



An etched surface does not give the slightest indication of Wid- 

 manstattian figures ; their, occurrence in short appears to be an excep- 

 tion rather than the rule in the case of irons containing more than 

 9 or 10 per cent, of iron (see page 80). 



Dr. L. Smith, while seeking for a satisfactory explanation of the 

 formation of these figures, expresses his belief that we shall not 

 arrive at a satisfactory explanation until our knowledge of the effect 

 of the presence of a minute quantity of foreign substances in iron is 

 better understood. He alludes to the power iron, containing one per 

 cent, or even a less amount of phosphorus, acquires of withstanding 

 the action of acid, as evidenced in vessels used for parting gold and 

 silver. During the crystallization of iron, as of other substances, 

 " there is a tendency to eliminate foreign constituents to the exterior 

 portion of the crystals " : after a blast-furnace, for example, has been 

 chilled and the metal has slowly passed from a plastic to a solid 

 condition, the iron will be found in large mystals containing a very 

 much smaller amount of carbon than is usually the case. If meteoric 

 iron then be rapidly brought to the solid state, we can conceive of 

 such a diffusion of the phosphorus as would give no marked indica- 

 tions in any part of the mass ; by slow cooling, however, we might 

 expect a more or less complete elimination of the phosphorus in 

 certain parts representing the spaces between the crystals of the 

 mass. " The portions of the iron forming the limits of the ci^stals 

 become more richly charged with phosphorus," the homogeneous 

 character of the " iron" is destroyed, and this would render its dif- 

 ferent parts variously susceptible to the action of an etching fluid. 



The irons of Victoria West, South Africa (see above), and Taze- 

 well Co., which enclose nodules of troilite and schreibersite, con- 

 tain, the former only a trace of sulphur and - 28 per cent, of phos- 

 phorus, the latter 0-016 percent, of phosphorus; and in the mass 

 of the Arva iron, which is filled with layers of schreibersite, there 

 remains only 0*019 per cent, of phosphorus. The geologist and 

 mineralogist have noticed such a segregation in a vast number of 

 instances. 



1863, March 16th. — Pulsora, N.E. of Rutlam, Indore, in Central 



India. 1 



In his descriptive catalogue of the meteorites in the Vienna Collec- 

 tion, which is dated 1st October, 1872, Tschermak describes this 

 stone as chondritic, and as consisting of olivine and bronzite with 

 nickel-iron. It occupies a place between those marked C w (white 

 rock without spherules) and C g (grey rock with light-coloured 

 spherules). The letters C i b, affixed to it in the catalogue, denote 

 that it has a brecciated structure like the meteorites of Dacca and 

 St. Mesmin. 



1 G. Tschermak. Mineralogische Mittheilungen, 1872, 165. 



