368 Dr. Walter Flight— History of Meteorites. 



(occluded) in the substance of the metal. The gas obtained from this 

 iron has been examined spectroscopically by Salet, who communi- 

 cated his results to the Societe chimique de Paris on the 1st March, 

 1872. His researches on the polar aurorae had led him to seek for 

 the yellowish-green ray (\=557), but he found only those due to 

 the presence of hydrogen and an oxide of carbon. It must be as- 

 sumed then that the carbon present in the iron, and which must be 

 very small in quantity, exists there not as carbide of iron, but as oc- 

 cluded carbonic oxide. 



1828.— La Caille, near Grasse, Alpes-Maritimes (formerly Dep. du 

 Var), France. 1 



Meunier has submitted the Caille iron to an exhaustive examination. 

 He finds, when etched, that it presents much the same appearances 

 as he noticed in the Charcas iron (see page 320) ; it consists of kama- 

 cite (chamasite ; E. S.Dana's "Second Appendix to Dana's System of 

 Mineralogy," 11) and tanite in much the same proportions. The 

 tanite has a specific gravity of 7-380 (von Eeichenbach in another 

 meteoric iron found the number 7-428) and the composition : — 



Iron = 85-0; Nickel (cobalt) = 14-0. Total = 99-0. 

 Iron = 85-0; Nickel (cobalt) = 15-0. Total = 100-0. 



numbers which indicate the formula Fe 6 Ni. 



The kamacite has the specific gravity 7-652, and consists of : 



Iron = 91-9 ; Nickel = 7-0. Total - 98-9. 



which is an alloy of the formula Fe 14 Ni. The entire iron appears to 

 contain about 80 per cent, of the latter alloy, and Meunier's numbers 

 correspond very closely with those obtained, by Kivot, who analysed 

 the metal in the bulk. 



The graphite of this iron, found in the residue after treating the 

 metal with hydrochloric acid, has a density of 1*715, and the compo- 

 sition : 



Carbon = 97*3 ; Iron = 2-4 ; Nickel = trace. Total = 997. 



The troilite of the Caille iron, after treatment with acid, left a small 

 amount of siliceous residue, which was precisely similar in its physical 

 characters to that found in the Charcas meteorite (see page 319). By 

 the action of heat and oxidizing agents figures were developed which 

 likewise bore the closest resemblance to those developed on the 

 Charcas iron. The accompanying woodcut gives a representation of 

 a block of this iron (actual size) which is in the Paris Collection. 

 It shows the Widmannstattian figures, developed by etching with 

 hydrochloric acid, and the reniform hollows which have been filled 

 with troilite. 



1 S. Meunier. Tbese presentee a, la Faculte des Sciences de Paris, 1869. Eecherches 

 sur la composition et la structure des Meteorites, 29, et seq. La Nature, i. 292. — 

 J. Boussingault. Compt. rend, lxxiv. 1287. Ann. Chim. et Phys. xxviii. 124. 



