434 J. L. Smith — Carbon Compounds in Meteorites, 



izing action upon the graphite from the Cranbourne meteoric 

 iron, and also upon the carbon from the Orgueil meteorite, and 

 found that, of the two, only the graphite from the meteoric iron 

 gave rise to the oxide. 



The study of this subject I have pushed further, and have 

 oxidized the graphites from the Sevier County and the De 

 Kalb County meteorites, and have also re-examined that of the 



Cranbourne iron — having been very liberally furnished with ; 

 specimen by my friend, Prof, Maskelyne, of the British Museum. 

 The carbonaceous matter from the Orgueil meteorite has also 



been subjected by me t 



The details of conducting the process were identically those 

 proposed by M. Berthelot in the memoirs already referred to, 

 viz : To free the powdered graphite from sulphide of iron by 

 first treating it with strong nitric acid, washing it thoroughly 

 on a filter, drying it and mixing it with five times its weight of 

 potash chlorate, then adding this mixture little by little to suf- 

 ficient fuming nitric acid to moisten thoroughly "the mass. In 

 making the mixture, I place the nitric acid iri a capsule and 

 the latter in a little water with a piece of ice, thus avoiding any 

 risk of explosion. The mixture, after standing a few hours is 

 transferred to a ballon d'assais, and gently heated in a water 

 bath at a temperature from 50° to 60^ C. for several days. The 

 result of this action upon the graphites of the Sevier County 

 and DeKalb County meteoric irons was the formation of graph- 

 itic oxide, with all the characteristics of that furnished to 

 Berthelot by the graphite from the Cranbourne iron, as well as 

 to myself from this last graphite. 



The conversion of the meteoric graphite into the oxide is 

 more rapid than that of any terrestrial graphite with which I 

 have experimented. The graphite soon changes from black ^ 

 green, and finally, after two or three applications of the oxid- 

 izing agent, to a perfectly white substance. This, when fil- 

 tered, washed, and dried under a bell glass with sulphuric acid, 

 gives a yellow powder, somewhat adherent If the oxidizing 

 action of the nitric acid and potash chlorate be renewed several 

 times on the same material, the oxide gradually diminishes m 

 quantity, and if the process be stopped after the fourth or fifth 

 treatment, the oxide is very gummy, adhering to the filter and 

 preventing complete washing. When dried on the filter it 

 adheres firmly, but can be detached by moistening the filter and 

 rubbing off the paper with the finger, leaving tenacious flaky 



The reaction and decomposition of the oxide obtained from 

 the Sevier graphite is the same as that of the oxide from other 

 sources. 



My experiments on terrestrial graphites have been confined 



