Liquid Fuel Engineering Company, of England, are jirominent. A De Dion omnilms built in 1897 had seats for Ifi passengers, was 21 feet long, and weighed, loaded, 4 tons 10.8 liun- dredweiglits. Of the total length, G% feet were taken up by the machinery, which consisted of a boiler, iriade up of two annular cylindrical vessels, one within the other, connected by water- tubes, and working at 200 pounds pressure, and a horizontal compound engine so arranged that live steam could be thrown into the low-pressure cylinder. In the Scotte vehicles a combined water-and-fire tube vertical boiler is used to drive a two-cylinder vertical engine. Both the IJe Dion and Scotte vehicles have gear-drives. In tlie omnibuses of the Liquid Fuel Engineering Company a special boiler of the water-tube type is em])l(jyed to drive a compound horizontal en- gine. This same machinery is applied by the company to its freight wagons.
The steam freight wagon has received par- ticular attention in England, and there are now a number of English concerns turning out wagons of this tj'pe capable of carrying loads of from two to six tons. The following are descriptions of four of these wagons, which competed in the trials of heavy-traffic motor vehicles, which were instituted by the Liver- pool Self-Propelling Traffic .Association in 1899. A vehicle built by the Thornyeroft Steam Car- riage and Wagon Company w'as 16 feet long by OV2 feet extreme width, with a steel frame and wooden wheels of the military ty])e. Tlie front wliccls were 2 feet 9 inches in diameter, and the driving-wheels 3 feet 3 inches, with 5'4-ineh tires on all. The boiler was of the well-known Thornyeroft curved water-tube typo with 82 square feet heating surface, 2.4 square feet grate area, and a test pressure of 250 pounds per square inch. The engine was of the horizontal, compound, reversing type, with 4 and 7 inch cyl- inders and 5-inch stroke, entirely inclosed in a dust-proof and oil-tight casing. The transmis- sion was bv pinions. A two-ton steam lorrv, built l«y T. Coulthard & Co., was fitte'd with a vertical fire-tube boiler. The heating surface was 77 square feet, and the working pressure was 200 to 225 pounds per square inch, with a test-pressure of 450 pounds ; liquid fuel was used with a Leyland burner. The engine was of the triple-expansion, vertical, uni-direc- tion type, with 2%, 4%, and 6 inch cylinders and 5-inch stroke, and was to develop 14 B. horse-power at 500 revolutions per minute. Power was transmitted to the driving wheels by means of spur gearing connecting the engine shaft and first-motion shaft, friction clutches being employed to put the gears into action. A 4-ton steam lorry, built by Clarkson & Capel, had a boiler of the fire-engine type, with small inclined cross-tubes of steel ; 06 square feet heating surface, supplemented by 14 square feet of cojiper feed-coil located in the up-take. The working pressure was 200 pounds and the test pressure 350 pounds to the square inch. Liquid fuel was used to generate steam supplied to- burner of the true Bunsen type. The engine was a vertical compound, reversing, with 2% and 6 inch cylinders and 4-inch stroke, develop- ing 14 B. horse-power at 000 revolutions. The engine shaft carried a two-spfied gear, with the higher speed put into engagement by an expand- ing clutch, and a Renald chain used to transmit power to the second motion. The Baglcys, of London, submitted a 3V^-ton steam lorry with a De Dion boiler, with 70 square feet heating surface and a working pressure of 200 pounds ; it IS centrally fired with coke. The engine was of the compound vertical, inverted, reversing type, with 4 and 7 inch cylinders and 5-inch stroke, developing 22 B. horsepower at 500 revo- lutions. Power was transmitted by bevel and spur gearing. It should be said that in all these vehicles the moving parts are inclosed in dust and oil-proof casings.
Gasoline Vehicle. Perhaps the most popular motor for automobiles is some form of oil-engine or internal-combustion motor. The number and variety of these vehicles and of the motors and their arrangement precludes indi- vidual description. An internal-combustion motor is one in which the propulsive power is given to the piston by the explosion of vapor- ized oil, such as benzine or gasoline, in the cylinder. The mechanism comprises, besides the engine and its connections, a carburetter for vaporizing and feeding the oil to the cylinder, and a cooler, by which w-ater is kept in circula- tion around the cylinder, which is being con- stantly heated by the successive explosions. ( See G.s Engine.) An internal combustion engine, like a steam-engine, transmits its power to a crank-shaft, from which it is led olf by a chain drive or gearing to the driving-shaft of the ve- hicle. These motors are made with one, two, and four cylinders, and are of various powers. The internal combustion engine, or explosive motor, differs chiefly from the steam-engine in that it works at a constant speed, and its motion is com- municated by systems of gearing and clutches to the wheels. It will not start up of itself under load, and cannot be reversed. Backing the car- riage is effected by gears, and a steady movement of the engine is produced by a fly-wheel. The gas- oline motor is unable to run under overload, but on the other hand consumes less fuel, and on this account has a greater radius of action.
Electric Vehicle-s. The equipment of the modern electric automobile consists of a storage battery for supplying the current, the motor for transforming this current into mechanical power, and the controller for regulating the speed of the motor. In most electric vehicles, two motors or a double-motor drive are em- ployed, the motor being either supported on the I'ear axle or on the reach. The battery is either placed in a case hung under the body of the vehicle or else inside the body. The motors and other moving parts are placed in dust-proof cases. The efficiency of the battery is of course the most important consideration, and its dete- rioration with service has to be borne in mind in such commercial applications as automobiles. In 1902 the batteries then in use were considered to be good for 5000 miles by observing ordinary pre- cautions in charging and use. In America elec- tric power has been applied to a great variety of vehicles, including, besides pleasure carriages of various types, delivery wagons, cabs, omnibuses, and trucks. Since 1900 in America 20-passenger omnibuses and heavy trucks with double electric motor drives have been constructed and are in active use. See Storage Battery; Dynamo-Electric Machinery.
The speed attained by the automobiles has been and is being enormously increased, and it is in
