Dr. Walter Flight — Eistory of Meteorites. 553 



The author suggests that more or less rounded masses of nickel- 

 iferous gothite or limonite having a similar origin may probably be 

 met with in the older sedimentary rocks. 



In continuation of his valuable researches on the native and 

 artificial varieties of carbon, 1 Berthelot examined a specimen of the 

 graphite-like carbon, which I found among the fragments of metal 

 detached from this iron. His object was to ascertain which variety 

 of carbon it resembled, whether it should be classed with the 

 graphite of pig-iron, native plumbago, the amorphous carbon obtained 

 by treating carbides of iron or manganese with acid, the so-called 

 artificial graphite of the gas-retorts which he had previously shown 

 to be no true graphite, anthracite, or, lastly, the carbonaceous sub- 

 stance found in the remarkable meteorite which fell at Orgueil- 

 (1864, May 14th). 3 



The carbon of the Cranbourne meteorite was warmed with nitric 

 acid to remove the iron sulphide, and then digested with fuming 

 nitric acid and chlorate of potash. After two treatments with these 

 powerful oxidising agents, Berthelot obtained a greenish graphitic 

 oxide, identical in every respect with the oxide obtained from the 

 graphite of cast iron, and differing as entirely from the oxidised 

 product which plumbago yields under like conditions. As this 

 meteoric carbon resembles in all respects the variety of this element 

 which has been dissolved in molten iron and separated from the 

 solidified mass after very rapid cooling, Berthelot suggests that its 

 formation and association with the meteoric form of iron sulphide 3 

 may be ascribed to the action of sulphide of carbon on incandescent 

 iron, since the carbon of the last-mentioned sulphide by decom- 

 position is also liberated in the graphitic form. The carbon of this 

 meteoric iron owes its present form to exposure to a very high 

 temperature ; it cannot have been produced by the action of 

 iron on carbonic oxide or from carbon once combined with the 

 metal and liberated at ordinary temperatures by the solution of the 

 iron in some reagent ; and is still further removed from the other 

 variety of meteoric carbon occurring in the stone of Orgueil. The 

 carbon of the Ovifak iron (see page 120) has likewise been examined 

 by Berthelot. He finds it to differ so completely in its behaviour 

 with oxidising reagents from the carbon of the Australian iron that 

 he does not hesitate to pronounce the conditions under which these 

 two forms of the element were produced to have been essentially 

 distinct. 



1 M. Berthelot. Ann. de Chim. et de Physique, xix. 405. 



2 Wohler and Cloez have found that certain of the carbonaceous meteorites con- 

 tain compounds of carbon, hydrogen, and oxygen, resembling the last residues of 

 organic substances of terrestrial origin. By applying his method of hydrogenation 

 to the carbonaceous matter of the Orgueil meteorite, he succeeded in forming a 

 notable quantity of a hydrocarbon of the series (C 2u H 2n + 2 ) comparable with the 

 oils of petroleum. This new analogy between the carbonaceous matter of meteorites 

 and substances of organic origin occurring in the crust of our planet is of great 

 interest. (C'ompt. rend., lxyii. 849.) 



3 Troilite in large nodules is abundantly present in this meteoric iron. 



