298 PROF. W. A. BONE AND OTHERS ON 



On the other hand, it has been proved in my previous researches upon hydrocarbon 

 combustion : ( 1 ) that in slow combustion in borosilicate glass bulbs at temperatures 

 between 300 C. and 400 C., methane, ethane, ethylene and acetylene are all oxidised 

 at a much faster rate than is either hydrogen or carbon monoxide,* and (2) that on 

 exploding such mixtures as C 2 H 4 + H 2 + O 2 or C 2 H 2 + 2H 2 + 02, the hydrocarbon is 

 burnt in preference to hydrogen, t facts which are at variance with LANDOLT'S 

 conclusion. 



The possibility of deducing from our bomb experiments a direct comparison between 

 the relative affinities of methane and hydrogen in explosions arose from the fact that 

 the primary oxidation of methane involves a direct transition from CH 4 +O a to 

 CH 2 (OH) 2 , which latter breaks up into, ultimately, CO + H 2 + H 2 O, without any 

 deposition of carbon. Whence it follows that if mixtures, CH 4 + 2 + a;H 3 , be exploded, 

 the division of the oxygen between the methane and hydrogen during the extremely 

 short period of actual combustion (i.e., direct oxidation) may be deduced from the 

 proportion of the original methane found intact in the final products, provided always 

 that there is no separation of carbon, which in fact is never observed in such 

 circumstances. 



The experimental method consisted, therefore, in exploding a series of mixtures 

 CH 4 + O 2 +a?H 2 , in which the hydrocarbon and oxygen were initially present in as 

 nearly as possible equimolecular proportions, but in which x (the volume ratio of H 2 

 to CH 4 ) was varied between 2 and 8, and determining from the percentage of the 

 original methane remaining intact in each case (l) the oxygen distribution when 

 x = 2, and (2) the influence upon such distribution of successive equal increments of 

 x up to 8. And in order to determine the possible influence of the walls of the 

 explosion vessel upon the results, parallel series of experiments were carried out in 

 each of the two bombs, A and B. 



In each case the mixture exploded with a distinctly audible sound, which 

 diminished in intensity as the proportion of hydrogen x increased, until with the 

 mixture CH 4 + O 2 + 8H 2 only a faint puff" could be heard. In no case was there any 

 separation of carbon. 



Before discussing the bearing of the results upon the matter under investigation, 

 it will be convenient to detail and summarise them in the following tabulated form. 

 (Tables IV. to VIII. inclusive.) 



* ' Trans. Cham. Soc.,' 1902, vol. 81, pp. 538 and 539 ; 1904, vol. 85, p. 694. 



t Ibid., 1906, vol. 89, pp. 669 and 670, also 'Proc. Royal Institution,' 1908-10, vol. 19, pp. 73 

 to 87. 



