[ 571 ] 



XVIII. Combiustion in Dined Oxyycn. 



By H. BREKETON BAKKK, M.A., Didwich College, late Scholar of Bnlliol College. 



Oxford. 



Communicated by Professor H. B. DIXON, F.R.S. 

 Received July 4, Read November 15, 1888. 



THE chemical changes occurring in combustion hold such an important position, not 

 only in the history and advance of chemical science, but also in the applications of 

 science to industry, that special interest is attached to the discovery of the nature 

 and order of the chemical changes involved. The phenomena presented by the 

 oxidation of carbon, sulphur, and phosphorus have been studied by chemists as 

 typical of those which are found in other processes of burning. With the object of 

 determining the conditions necessary for the oxidation of these three substances, I 

 began in 1884 an investigation, the results of which are described in the following 

 paper. That water vapour might play an important part in such actions seemed very 

 probable. The interesting facts brought to light by my former tutor, Professor H. B. 

 DIXON, with regard to the oxidation of carbon monoxide (' Phil. Trans.,' 1884) made 

 it seem likely that water vapour might exert as strong an influence on other combus- 

 tions as he has shown it does on that of carbon monoxide. It was suspected some 

 years ago that the combustion of carbon is affected by the presence or absence of 

 moisture. In 1871 M. DUBKUNFAUT read a paper before the Academic des Seirnces 

 describing some experiments bearing on this point. He had performed combustions of 

 sugar-charcoal in oxygen dried by strong sulphuric acid, and found that the carbon did 

 not undergo combustion as readily as it did if the oxygen was moist. He ascribed 

 the incompleteness of the oxidation of the carbon to the presence of moisture which 

 was inaccessible to our reagents, that is, moisture which did not cause a weighed 

 sulphuric acid tube through which it was passed, to increase in weight. A few weeks 

 later M. DUMAS, who had determined the equivalent of carbon by burning a weighed 

 quantity of pure graphite in pure oxygen, repeated the experiments, and, by using a 

 large quantity of the partially dried oxygen, succeeded in burning the whole of a 

 small quantity of graphite. 



In my first experiments on the combustion of carbon in oxygen,* wood charcoal was 

 employed. It was freed from hydrogen by heating in a current of chlorine for several 

 hours. It was placed in glass tubes, into which phosphorus pentoxide had been 



' Chem. Soo. Journ.', 1885, Traru. p. 349. 



4 D ~t 12.1 



