Page:Experimental researches in chemistry and.djvu/186

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^[1], 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.
		Sul. Acid.		in 8'	in 1 hour	2 hours.	Dimin. per cent.
188	vol.	+09.5	vol. diminished to	155.0	148.5	146.4	22.12
107		+ 13.0		88.5	84.5	82.0	23.33
138		+05.2		113.7	108.0	106.5	22.82
Oil-gas from Gordon's Lamp.
		Sul. Acid.		15'	30'	3 hours.	Dimin. per cent.
214	vol.	+ 6.8	vol. diminished to	183.3	180.8	176.0	17.75
159		+05.9	..............	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 separate 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.

1. 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.