The old-time automobiles were cumbrous affairs, with clumsy boilers, and steam-engines that required one man’s entire attention to keep them going.  The concentrated fuels were not known in those days, and heat-economising appliances were not invented.

It was the invention by Gottlieb Daimler of the high-speed gasoline engine, in 1885, that really gave an impetus to the building of efficient automobiles of all powers.  The success of his explosive gasoline engine, forerunner of all succeeding gasoline motor-car engines, was the incentive to inventors to perfect the steam-engine for use on self-propelled vehicles.

Unlike a locomotive, the automobile must be light, must be able to carry power or fuel enough to drive it a long distance, and yet must be almost automatic in its workings.  All of these things the modern motor car accomplishes, but the struggle to make the machinery more efficient still continues.

The three kinds of power used to run automobiles are steam, electricity, and gasoline, taken in the order of application.  The steam-engines in motor-cars are not very different from the engines used to run locomotives, factory machinery, or street-rollers, but they are much lighter and, of course, smaller—­very much smaller in proportion to the power they produce.  It will be seen how compact and efficient these little steam plants are when a ten-horse-power engine, boiler, water-tank, and gasoline reservoir holding enough to drive the machine one hundred miles, are stored in a carriage with a wheel-base of less than seven feet and a width of five feet, and still leave ample room for four passengers.

It is the use of gasoline for fuel that makes all this possible.  Gasoline, being a very volatile liquid, turns into a highly inflammable gas when heated and mixed with the oxygen in the air.  A tank holding from twenty to forty gallons of gasoline is connected, through an automatic regulator which controls the flow of oil, to a burner under the boiler.  The burner allows the oil, which turns into gas on coming in contact with its hot surface, to escape through a multitude of small openings and mix with the air, which is supplied from beneath.  The openings are so many and so close together that the whole surface is practically one solid sheet of very hot blue flame.  In getting up steam a separate blaze or flame of alcohol or gasoline is made, which heats the steel or iron with which the fuel-oil comes in contact until it is sufficiently hot to turn the oil to gas, after which the burner works automatically.  A hand air-pump or one automatically operated by the engine maintains sufficient air pressure in the fuel-tank to keep a constant flow.