As the automobile, a chemical factory on wheels, converts gasoline and air into energy for propelling itself and its load, its prinicpal problems of operation center on the properties and impurities of the raw materials, the utilization and disposition of the by-products and the proper maintenance of the plant equipment.
After discussing the nature of gasoline, the author enumerates the five sources from which motor fuel is derived. The major part of the gasoline is said to be obtained directly by distillation from petroleum; about one-quarter of American gasoline, to be secured by the cracking of heavier petroleum oils; about one-tenth, to be gasoline that is separated from natural gas; from 1 to 2 per cent, to consist of benzol and similar material; and fuel used in some sugar-producing localities, to comprise alcohol made from molasses.
Among the service problems arising from the use of gasoline is mentioned the presence, in some cracked distillates that have not been properly refined, of a brown varnish-like resin, the formation of which increases with the age of the liquid and the warmth of the place of storage.
Another source of trouble is due to the fact that resinous material tends to collect dirt. If later a blended fuel containing benzol or alcohol is added, the resinous deposit is loosened or dissolved, releasing the dirt, which then collects and clogs screens and small openings.
A gasoline engine manufactures considerable quantities of water. In cold weather, condensed water in the cylinders may form ice and freeze the pistons. Sulphur oxides produced by the combustion of the fuel dissolve readily in water, forming sulphuric acid, which has a corrosive effect on the polished surface of the cylinders and the bearing surfaces in the crankcase. The three remedies proposed are (a) prevention of condensation or the collection of liquid water in the engine, (b) removing the water after it has been formed and (c) using a fuel low in sulphur.
Although most of the fuels in common use are blends of the materials obtained from the first three sources mentioned above and are generally satisfactory, means of accurately determining their characteristics are not usually available and the service man must use his best judgment in selecting them. If gasoline could be made to conform to a universal standard, so far as the volatility characteristics are concerned, the design, operation and servicing of automobiles would be greatly benefited. Surveys having shown that most automobiles use more fuel than is necessary, the suggestion is made that the running qualities of many cars could be improved if the carbureters were adjusted for leaner mixtures, and a plea is made for the conservation of the available fuel-supply.
Attention is called to the hazards arising from the inflammability of the fuel and from the poisonous character of exhaust gases, and suggestions are given with a view to their prevention.


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