1886.] 



on "Recent Researches on Meteorites, 



549 



and indeed smelt strongly of sulphurous acid. On evaporating it to 

 dryness with a drop of hydrochloric acid, abundance of ammoniacal 

 salts were found in the residue. In the cool anterior part of the 

 comhustion-tube a considerable sublimate had collected, which proved 

 to be principally sulphate of ammonium with traces of sulphides and 

 sulphites, and a large quantity of free sulphur. A very large quan- 

 tity of gas was given off, having the following composition : — 



Sulphurous acid is evidently the main constituent of the gases given 

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

 of the sulphate of iron, be- eliminated, 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. : — 



CO2, 76-05; CO, 11-67; CH4, 8-93; N, 3-33. 



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

 carbon 63 • 45, hydrogen 6 • 98, oxygen 30 • 57, which is nearly in the 

 proportions of a terrestrial humus substance. It is known that such 

 substances 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. 



It may be assumed 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 it points 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. 



It is proposed to continue this investigation, and in order to 

 acquire further information, 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 



