n. The lightest volatile liquid product commonly obtained from the distillation of petroleum.n. Its principal hydrocarbon constituents are hexane and heptane, C6H14 and C7H16, in varying proportions. It boils between 149° and 194° F. and gives off a vapor under atmospheric tension at all temperatures. The vapor of gasolene is 3.05 times as heavy as air. The volatile elements distil off on storage, unless the containing-vessels are very tight. Its calorific power is about 18,000 B. T. U. It is much used in the internal-combustion motors of motor-cars and motor-boats.