36 Prof. H. E. Armstrong. [June 9, 



[D 7200, 0550 - Oe]. 



"The Ketardation of Combustion by Oxygen." By HENRY E. 

 ARMSTRONG, Ph.D., F.K.S. Keceived June 9, Kead June 16, 

 1904. 



In the course of his researches on gaseous explosions, H. B. Dixon 

 has laid stress on the fact that carbon monoxide, rather than the 

 dioxide, is the initial product of the combustion of carbon and of its 

 gaseous compounds; moreover, he has shown that water plays a 

 peculiar and all-important part in the combustion of the monoxide ; 

 and he has proved, in a number of cases, that oxygen is by far the 

 most effective diluent in retarding combustion. These, in some 

 respects, paradoxical conclusions have not yet been sufficiently 

 explained. Recent researches* emanating from the Manchester 

 school have brought new facts to light, however, which have an 

 important bearing on the interpretation of explosive changes so 

 much so, indeed, that it is no longer difficult to paint a consistent and 

 fairly complete picture of the mechanism of combustion.! 



1. It would seem that, in tne case of hydrocarbons, there is no 

 preferential combustion either of hydrogen or of carbon : initially, 

 the hydrocarbon merely undergoes hydroxylation. As hydroxylation 

 proceeds more readily when it has once taken place owing to the 

 attraction of oxygen for oxygen the first product may easily escape 

 observation: thus, Bone and Wheeler were unable to detect the 

 formation of hydroxymethane (methyl alcohol) from methane ; Bone 

 and Stockings, however, succeeded in obtaining ethyl alcohol, C 2 H 5 OH, 

 from ethane, C 2 H 6 . 



!. A stage in the hydroxylation is soon reached when thermoschisms 

 begin to take place. Thus, dihydroxymethane breaks up as soon as it 



formed into water and formaldehyde, which is in turn easily 

 resolved into hydrogen and carbon monoxide : 



CH 2 (OH) 2 - , CH 2 + OH 2 - 



Dihydroxyethane, in like manner, gives rise to acetaldehyde, which, 

 wine conditions, breaks up into methane and carbon monoxide : 



C 2 H 4 (OH) 2 -H. CH 3 .COH + OH 2 - . CH 4 + CO + OH. 



V' Wheeler > "The Slow Oxidation of Methane at Low 



of Combustion," HU., 1903, 



