1825.] obtained by the Decomposition of Oil. 171 



a length of time which appears to be quite sufficient for the 

 removal of any of the peculiar vapours from oil or coal-gas. 



My mode of operating was generally in glass tubes over 

 clean mercury*, introducing the gas, vapour or mixture, and 

 then throwing up the sulphuric acid by means of a bent tube 

 with a bulb blown in it, passing the acid through the mercury 

 by the force of the mouth. The following results are given as 

 illustrations of the process : 



Oil-gas from a Gasometer. 



Dimin. 

 Sul. Acid. in 8'. in 1 hour. 2 hours, per cent. 



188 vol. + 9-5 vol. diminished to 155'0 148'5 146'4 22-12 



107 + 13-0 88-5 84-5 82'0 23-33 



138 + 5-2 113-7 108-0 106'5 22'82 



Oil-gas from Gordons Lamp. 



Dimin. 

 Sul. Acid. 15' 30' 3 hours, per. cent. 



214 vol. -f 6-8 vol. diminished to 183'3 180*8 176'0 1775 



159 4 5-9 137'5 136-0 130-4 17'98 



113 + 12-2 98-0 96-0 92'0 18'58 



Coal-gas of poor quality. 



548-6 + 27'6 533-3 529-2 529*0 3'57 



273-6 + 27-8 267-9 266-0 266-0 2'78 



190-6 + 13-1 186-0 184-2 184-1 3'41 



Oil may also be used in a similar manner for the separation 

 of these vapours. It condenses about 6 volumes of the most 

 elastic vapour at common temperatures, and it dissolves with 

 greater facility the vapour of those liquids requiring higher 

 temperatures for their ebullition. I found that in mixtures 

 made with air or oxygen for detonation, I could readily se- 

 parate the vapour by means of olive oil ; and when olefiant and 

 other gases were present, its solvent power over them was 

 prevented by first agitating the oil with olefiant gas or with a 

 portion of the gas to saturate it, and then using it for the 

 removal of the vapours. 



* If the mercury contain oxidizable metals, the sulphuric acid acts upon 

 it, and evolves sulphurous acid gas. It may be cleaned sufficiently by being 

 left in contact with sulphuric acid for twenty-four hours, agitating it frequently 

 at intervals. 



