

MOTOR CARRIAGES. 



469 



Steering is sometimes done through the ordinary 

 king-bolt method, but oftener, and with better re- 

 sults, by individually pivoting each front wheel at 

 the end of the axle and causing them to turn 

 through the proper angles by a system of links 

 connected to the hand-steering lever. As can be 

 readily seen, the latter leaves various opportunities 

 for improving the faults of steering at high speeds 

 which do not exist in the former. 



Speed control is closely associated with the char- 

 acter of the motive power. In the case of the steam 

 carriage, variations of speed are obtained by some 

 form of link motion, exactly as is done with the 

 ordinary locomotive. In the case of the gasoline 

 engine, the speed can not be varied beyond certain 

 comparatively narrow limits which have proved 

 acceptable to the users, and it becomes necessary 

 to use two or more separate trains of gears, and 

 different speeds are obtained through the medium 

 of a gear-shifting device which transmits the power 

 of the engine through any of the gearing trains de- 

 sired. The electric carriage lends itself most readily 

 to the matter of speed control, and mere changes in 

 the battery connections sufficient to alter the vol- 

 tage applied at the motor is all that is needed to 

 get speed gradations. 



Brakes of all descriptions are employed upon 

 motor carriages, and this is, as may be seen, a 

 question of vital importance. Some form of band 

 brake operated by a foot lever is the most usual and 

 satisfactory, but tire brakes consisting of a broad 

 shoe pressed against the periphery of the tire are 

 in common iise, especially on European carriages. 

 The builders of electric vehicles often fit them with 

 some form of electric brake, the usual principle of 

 operation being the retardation or magnetic drag 

 effected by running a motor as a dynamo through 

 the momentum of the carriage. The employment 

 of current generated in this way for recuperating 

 the batteries is limited to hills of more than ordi- 

 nary inclination, such as grades of 10 per cent, 

 or more. 



Speed. The speed of an automobile can be made 

 ; almost anything that the condition of the road 

 and the intrepidity of the driver will permit. In 

 France the maximum speed of automobiles is not 

 limited by the character of the road surface, and 

 for special purposes great speeds are obtained ; but 

 in current literature the speed of the French car- 

 | riages has been greatly overstated, and this fact 

 j has even been carried into the reports of French 

 societies interested in the art. Few French car- 

 riages have speeds exceeding 20 miles an hour, and 

 in the autumn of 1898 the best obtainable evidence 

 indicated that but 3 automobiles in France had a 

 maximum speed on the level of more than 25 miles 

 an hour. Of these 3 but 1 had a speed of more 

 than 30 miles an hour, and this was one which was 

 reported to have gone from Paris to Amsterdam 

 at an average speed of 25 miles an hour, and was 

 driven by Baron De Knyff, who with Charron and 

 Bollee holds the front rank among the automobile 

 drivers. Such speeds as these are out of the ques- 

 tion over any but the very best roads. In cities 

 j this fact, combined with police regulations, places 

 I at 12 miles an hour the maximum speed to be pro- 

 ; vided by the builder. 



Steam Carriages. The application of steam to 

 automobiles presents no novelty in principle, for 

 exactly the same character of engine is required as 

 ou the ordinary locomotive, though of course lighter 

 and less powerful. The real obstacle in the way of 

 a successful steam vehicle lies in the care and at- 

 tention necessary to bestow upon the boiler and its 

 accessories. Simple as is the steam carriage in 

 most particulars, its operation under the best con- 

 ditions requires the full attention of a trained 



mechanic. Up to the present steam transportation 

 has been reasonably successful only where condi- 

 tions of operation and current wages of operators 

 have not prohibited the employment of two oper- 

 ators, or where the speed has been reduced to such 

 an extremely low mark as to require the supervision 

 of but one man. The most successful system of 

 steam-carriage propulsion is probably that devised 

 by M. Serpollet, a Frenchman. This has been ap- 

 plied with success to heavy omnibuses, vans, road- 

 tractors, and tramways, but, by reason of the great 

 weight of boiler required, is not applicable to the 

 lighter class of road vehicles. His invention, in 

 brief, consists of a peculiar form of boiler which he 

 terms an instantaneous steam generator. It is a 

 water-tube boiler, the tubes being made of steel 

 pipes with very thick walls and flattened out so as 

 to leave a small slit which is called the capillary 

 space. These tubes are exposed to a very hot 

 flame, and, containing as much highly heated metal 

 as they do, are not cooled by the small amount of 

 water passing through the interior slit, but instant- 

 ly vaporize it, and the interior walls maintain their 

 temperature by conduction of heat from the exte- 

 rior. It is claimed that this boiler can be run for a 

 long time without injury with no water whatever 

 in the tubes, and in fact it is by regulating the 

 amount of water fed to the boiler that Serpollet 

 obtains his variations of speed. Since the boiler is 

 without capacity that is, all the steam generated 

 immediately passes into the engine the moment 

 the water ceases flowing the engine stops. The 

 greater number of steam carriages use some form 

 of tubular boiler which is non-explosive, and apply 

 the heat through a gasoline burner, this being the 

 most convenient fuel obtainable. Among the steam 

 vehicles in commercial use maybe mentioned a line 

 of goods vans, built by the Liquid Fuel Engineering 

 Company of London, and operated between London 

 and Birmingham. 



Petroleum or (gasoline Carriages. To this 

 class belong all those vehicles employing engines 

 or motors actuated by the explosion of hydrocarbon 

 vapors. The Otto principle of explosion engine is 

 used almost exclusively. It consists of a cylinder 

 and piston, which act alternately as pump and 

 motor that is, there is one effective or working 

 stroke only in two revolutions of the crank shaft. 

 At the first forward stroke a mixture of air and 

 gas is sucked in; on the return stroke this is com- 

 pressed; on the second forward stroke this mix- 

 ture is ignited by one of several ways, and an 

 explosion results, driving the piston forward, and 

 storing up the resulting surplus energy in a fly- 

 wheel which is large enough to do the work re- 

 quired of the engine between the separate working 

 strokes. On the second return stroke the exhaust 

 or burnt gas is expelled. The application of ex- 

 plosive engines to carriages was never successful 

 until the principle of the compressed charge was 

 applied. Explosion engines used upon motor car- 

 riages almost universally employ the vapor of com- 

 mon gasoline to form the explosive mixture. This 

 is obtainable anywhere, and is a cheap and con- 

 densed form of 'fuel. With few exceptions, the 

 gasoline is vaporized and intimately mixed with 

 air before entering the explosion chamber. The 

 device for vaporizing the oil is known as the car- 

 buretor, and in its simplest form consists of a tank 

 containing a certain amount of gasoline, through 

 which air is drawn by the suction of the piston, be- 

 coming saturated in its passage with the vapor of 

 the volatile oil. This vapor, however, must be min- 

 gled with a certain amount of air before a truly 

 explosive mixture is reached, and this is accom- 

 plished through some form of regulating valve 

 which permits the control of the richness of the 



