.558 



On the Gaseous Constituents of Meteorites. [June 10, 



Occluded gases Percentage composition. 



in vols, of the f K ^ 



Sp. gr. meteorite. C0 2 . CO. CE 4 . N. S0 2 . 

 Orgueii meteorite 2*567 57'87 1277 1*96 T50 0"56 83*00 



Sulphurous acid is evidently the main constituent of the gases given 

 off ; but if we eliminate this gas, which has been formed from the 

 decomposition of the sulphate of iron, we find the meteorite yields 

 9*8 times its volume of gas, having very much the same composition 

 as that from some of the stony meteorites, viz. : — 



C0 2 , 76-05; CO, 11-67; CH 4 , 8 93; N, 3 33. 



Cloez found the organic matter in this meteorite to be composed of 

 carbon 63*45, hydrogen 5'98, oxygen 30'57, which is nearly in the 

 proportions of a terrestrial humus substance. We know such sub- 

 stances break up by the action of heat into gases of the nature found 

 above, at the same time, however, a quantity of the carbonic acid 

 undoubtedly comes from the presence of the carbonates of magnesium 

 and iron. The operation by which terrestrial carbon has been 

 changed into graphite is by no means clear. As a rule the transition 

 of one kind of carbon into another necessitates the action of a very 

 high temperature. If, therefore, a really high temperature is in all 

 cases necessary, it is difficult to explain how compounds of carbon 

 came to resist decomposition, and should come to be found associated 

 with all natural graphites. 



We may assume that the graphite resulted from the action of 

 water, gases and other agents, on the carbides of the metals, and that 

 during the chemical interactions which took place, a portion of the 

 carbon became transformed into organic compounds. 



In either case we are led to the conclusion that the method of for- 

 mation of the meteoric and terrestrial graphites was similar, and it is 

 perfectly possible they may after all have come from a common 

 source. 



We purpose continuing this investigation, and in order to acquire 

 further information, it is our intention to examine the gases given off 

 from meteorites at definite temperatures, and especially the gases 

 from such as can be found coated with an impervious glaze, and to 

 examine more particularly into the presence of water in such bodies, 

 and the source of the nitrogen found in the same. 



Note. 



Since the above analyses of different graphites were made, we have 

 examined a sample of the artificial graphite which results from the 

 action of oxidising agents in the cyanogen compounds present in 

 crude caustic soda. The following analysis shows that this artificial 



