1886.] On the Gaseous Constituents of Meteorites. 551 



found imbedded in the iron meteorites, and to the nature of the 

 carbon in the so-called carbonaceous meteorites. He extracted^ the 

 organic or hydrocarbon-like bodies by means of ether, but did not 

 determine the gases given off on heating. Previous to this, Roscoe 

 (" Pro. Phil. Soc. Man.," 1862) had obtained the same hydrocarbon- 

 like body by exhausting the Alais meteorite with ether, but the 

 quantity he had to work upon was so small that he could not make a 

 very complete examination. 



These are some of the principal points that have been made out 

 with regard to the gases occluded by meteorites. The results, however, 

 are so comparatively few, that we thought it worth while to take the 

 opportunity which presented itself, of having several good specimens 

 of meteorites at our disposal, to confirm these results, and, if possible, 

 add something to our present knowledge of the subject. 



The investigation may be divided into five parts, having the follow- 

 ing objects in view : firstly, the confirmation of previous results by the 

 examination of some well-known meteorite ; secondly, the analysis of 

 several whole meteoric stones, whose interior had never been exposed 

 to the effects of the atmosphere, by reason of the characteristic coating" 

 of glaze ; thirdly, the examination of a celestial graphite nodule, taken 

 from the interior of an iron meteorite ; fourthly, the comparison of 

 some meteorite of the carbonaceous class with the above ; and, fifthly, 

 the examination of different terrestrial graphites. 



The method employed for the abstraction of the gases was exactly 

 the same in every case, so that a short description will suffice for all. 

 The temperature was kept as nearly as possible the same in every 

 experiment, but no doubt differences of many degrees occurred in 

 some of the experiments, which was unavoidable in using an ordinary 

 combustion furnace. 



The meteorite or graphite, as the case might be, was broken up into 

 a coarse powder, introduced into a convenient length of combustion 

 tubing, and connected up with a Sprengel pump, a small bulb-tube 

 immersed in a freezing mixture intervening, so as to retain any 

 moisture or condensable volatile products that might come off. The 

 tube was first thoroughly exhausted and then heated in an ordinary 

 gas combustion furnace to a low red heat. The gases, during the 

 heating, were gradually drawn off by the Sprengel, and when the tube 

 had remained for several minutes at a low red heat it was completely 

 exhausted. The total quantity of gas collected was in every case used 

 for the analysis. 



The " Dhurmsala " specimen was an ordinary fragment of a much 

 larger original mass, but in the case of the Pultusk and Mocs 

 meteorites, we were fortunate in obtaining complete stones, weighing 

 respectively 57 and 103 grams, having the characteristic black glaze 

 on their surfaces. 



