GASOLINE

a volatile liquid obtained from petroleum or natural gas. Strictly speaking, gasoline is that fraction occurring between petroleum ether and the heavier naphthas, or kerosene, but it frequently contains considerable proportions of the lighter fractions, known as cymogene, rhigolene and petroleum ether, and, especially during recent years, of the heavier fractions known as heavy naphthas. It is obtained by distillation of crude oil, or by extraction from natural gas, or by ‘cracking’ the heavier fractions of petroleum. The cracking proce consists of decomposing the oils by heat, under pre ure. Chemically, gasoline consists of a mixture of hydrocarbons, hexane, C.Hi4, being the largest constituent. Most commercial gasolines boil between 90° and 220° F. and have a specific gravity ranging between 0.635 and 0.750, but there is a constant tendency to raise the boiling point and the specific gravity in order to include a greater proportion of the heavier fractions and so increase the supply to meet the enormous demand for motor fuel. Extended tests made by the U.S. Bureau of Standards in the summer of 1922 indicated that there was no lo of power or mileage when the heavier grade of gasoline was used. Apparently the chief disadvantage is a greater difficulty in starting the engine and this is noticeable only during the colder months. It is claimed by unofficial observers that once the engine is hot the heavier fractions give steadier and greater power, and that provided the gasoline contains a sufficient proportion of the more volatile fractions to insure a quick start, the heavier grades are actually preferable, This point, however remains in doubt. In addition to its use as a motor fuel, gasoline finds extended application as a solvent, in dry cleaning, in the manufacture of rubber solutions, and in the preparation of certain grades of paint.