592 Dr. Walter Flight — History of Meteorites. 



superficial view of the exterior gives no indication. It appears to 

 resemble an ordinary meteoric iron, but when sawn through it is 

 found to enclose siliceous fragments, black in colour, markedly 

 angular, and varying in size from a few millimetres to two centi- 

 metres ; in these in some cases lie embedded grains of nickel-iron 

 and spherular particles of troilite. Troilite, as well as occasionally 

 little pieces of schreibersite, are also observed in the metallic portion. 

 According to Domeyko this iron consists of : 



Nickel-iron 95-92 



Schreibersite l - 42 



Silicate , ... ... 2-40 



99-74 



Meunier found in one specimen 1*7 per cent, of silicate. The 

 siliceous portion is distributed sparsely and so irregularly throughout 

 the mass that it is impossible to judge with any accuracy of the 

 composition of the meteorite en bloc. 



A portion of the siliceous ingredient from which a great part of 

 the metal had been detached had the composition : 



Nickel-iron 12-62 



Troilite (?) ... 6-01 



Chromite, schreibersite and graphite... traces 



Soluble silicate 40-82 



Insoluble silicate 41-55 



100-00 



Domeyko found the nickel-iron and schreibersite to consist of: 



Iron = 90-88; Nickel = 9-12 = 100-00 



Iron = 65-00 ; Nickel = 26-30 ; Phosphorus = 8-70 = 10000 



The density of the iron = 7-51 ; it does not show Widmannstattian 

 figures when etched, although small plates enclosed in the alloy de- 

 velope a pattern. The numbers yielded by the analysis of the phos- 

 phide correspond with the formula Fe 4 Ni g P. 



Meunier adopted a novel means for analysing the nickel-iron : he 

 reduced it to fine particles with a hard file, and fused them with 

 caustic potash in a silver crucible ; in this way the sulphur and 

 phosphorus of the troilite and schreibersite are rendered soluble and 

 removed with water. To ensure a perfectly pure condition of the 

 metal it is treated with fuming nitric acid, and is then dried and 

 heated cautiously in a current of air ; when the requisite temperature 

 is reached the particles change colour, those acquiring a blue tint 

 are kamacite, Fe u Ni, and those a yellow are tanite, Fe 6 Ni. In the 

 case of the Deesa iron nearly all the particles turned blue, a yellow- 

 grain being observed here and there. Meunier finds the composition 

 of the nickel-iron, iron sulphide and schreibersite to be : 



I. Iron = 91-4 ; Nickel = 7-2 = 98-6. 



II. Iron and Nickel = 58 ; Sulphur (calculated) = 42 = 100. 

 III. Iron = 60-00 ; Nickel = 26-75 ; Phosphorus = 10-29 = 97"04. 



Wiss. Wien, 1870, lxi. 26. La Nature, 1873, i. 405.— W. von Haidinger. Sitzber. 

 Ah. Wiss. Wien, 1870, lxi. 29.— See also G. A. Daubree. Compt. rend., 1868, lxvi. 

 571. 



