ELECTRICITY DURING THE NINETEENTH CENTURY. 349 



The motor car, or car propelled b}' its own motors, has also been 

 introduced upon standard steam roads to a limited extent as a supple- 

 ment to steam traction. The earliest of these installations arc the one 

 at Nantasket, Mass., and that between Hartford and New Britain, in 

 Connecticut. A number of special high-speed lines using- similar plans 

 have gone into operation in recent years. The problem of constructing 

 electric motors of sufficient robustness for heavy work and controlling 

 them effectively was not an easy one, and the difficulties were increased 

 greatly because of the placing of the motors under the car body, 

 exposed to wet, to dust, and dirt of road. The advantage of the motor 

 car or motor-car train is that the traction or hold upon the track 

 increases with the increase of the weight or load carried. It is thus 

 able to be accelerated rapidly after a stop and also climb steep grades 

 without slipping its wheels. Nevertheless there are circumstances 

 which favor the employment of a locomotive at the head of a train, as 

 in steam practice. This is the case in mines where trains of coal cars 

 or ore cars are drawn by electric mining locomotives. Many such 

 plants are in operation, and at the same time the electric power is used 

 to drive fans for ventilating, pumps for drainage, electric hoists, etc., 

 besides being used for lighting the mines. The trains in the tunnels 

 of the Metropolitan Underground Railway of London have for many 

 years been operated l)y steam locomotives, with the inevitable escape 

 of steam, foul, suffocating gases, and more or less soot. 



A number of years ago the tunnel of the City and South London 

 Railwa}' was put into successful operation with electric locomotives 

 drawing the trains of cars, and the nuisance caused by steam avoided. 

 This work recalls the early efforts of Field, of Daft, and Bentley & 

 Knight in providing an electric locomotive for replacing the steam 

 plant of the elevated roads in New York City. Well conceived as 

 many of these plans were, electric traction had not reached a sufficient 

 development, and the efforts were abandoned after se\eral more or 

 less successful trials. It is now seen that the motor-car train may 

 advantageously replace the locomotive-drawn train in such instances as 

 these elevated railways. 



The three largest and most powerful electric locomotives ever put 

 into service are those which are employed to take trains through the 

 Baltimore and Ohio Railroad tunnel at Baltimore. They have l)cen 

 in service about seven or eight years, and are fully equal in power to 

 the large steam locomotives used on steam roads. Frc(}uently ti-ains 

 of cars, including the steam locomotive itself, are di'awn through the 

 tunnel by these huge electric engines, the tires on the steam machines 

 being for the time checked so as to prevent fouling the air of the 

 tunnel. There was opened in London in 1900 a new railway, called the 

 Central Underground, equipped with twenty-six electric locomotives 

 for drawing its trains. The electric and power equipment, which 

 SM 1900 25 



