The two chief definite gaseous compounds of these two elements are the light carburetted hydrogen, and the heavy carburetted hydrogen, or olefiant gas. The first is easily procured by stirring the bottom of stagnant water on a hot summer’s day, and collecting the bubbles in a bottle filled with water and inverted over the place where the bubbles rise. This gas burns with a yellowish flame, and when mixed with a certain proportion of air, or oxygen gas, explodes with great violence on the application of a flame. It is the much dreaded fire-damp generated so profusely in some coal-mines, and causing such fearful destruction to life and property when accidentally inflamed.
The other compound, the heavy carburetted hydrogen, forms part of the gas used for illumination; and, in fact, whatever substance is employed for artificial light, whether oil, tallow, wax, &c. &c. it is converted into this gas by heat, and then furnishes the light by its own combustion.
This gas has some very curious properties, and may be obtained nearly pure by mixing in a retort, very carefully, one part of spirits of wine and four of sulphuric acid. A lamp must be placed under the retort, when the gas will be speedily disengaged, and come over in great abundance; it may be collected over water.
This gas is transparent, colourless, will not support combustion, but is itself inflammable, burning with a brilliant white light, and being converted into carbonic acid and water. If mixed with three or four times its bulk of oxygen, or with common atmospheric air in much larger proportions, it explodes with great violence.
This gas is sometimes called “olefiant gas,” from the property it has of forming an oily substance when mixed with chlorine.
JAR FOR COLLECTING GASES.
EXPERIMENT.
Into a jar standing over water half full of this gas, pass an equal quantity of chlorine gas. The gases will speedily unite and form an oily-looking liquid, which may be collected from the sides of the jar as it trickles down. By continually supplying the jar with the two gases as they combine, a considerable quantity of this substance may be collected. Care should be taken that the olefiant gas is rather in excess.
The substance produced is insoluble in water, with which it should be washed by shaking them together in a tube, and has a pleasant sweetish taste and aromatic smell, somewhat resembling ether.