1904.] on New Develop nients in Electric Railways. 465 



recourse is had to higher pressures at the generators, which is con- 

 verted into the working pressure either by rotary converters and 

 transformers, when the generators produce three-phase currents, or 

 by the three-wire system with modifications, when the generators 

 produce continuous currents of high pressure. 



A fair example of a modern railway on these lines is the elevated 

 railway of Berlin, which, however, in some parts dij)S under the level 

 of the streets. 



Messrs. Siemens and Halske have kindly lent a number of slides, 

 which show the endeavours that have been made to mitigate the 

 innate hideousness of an iron structure in the streets. 



Some other features of this railway also deserve attention : one 

 is the method of building a square channel immediately under the 

 carriage-way of the streets, which is supported by transverse iron 

 girders. The shallow tunnel, thus formed, can be readily ventilated, 

 and is easily accessible. 



In New York a similar construction has been adopted for the 

 new underground line, which will soon be ready for opening. 



Another feature of the Berlin line is the way of connecting the 

 main line with the short branch leading at right angles from it to 

 the Potflsdamer Platz. The lines form a triangle, and are rising or 

 dipping from the corners of the triangle in such a way that no 

 down line crosses an up line at the same level. 



All the points for directing the trains to and from the various 

 lines are moved electrically, on the lock-and-block system, from one 

 signal cabin placed at a high level, so that the signalman has a good 

 view of all trains approaching the triangle. 



Another attempt to transport j)assengers without interfering with 

 other traffic has been made by Messrs. Schuckert of Niirnberg, who 

 have built a line in Elberfeld and Barmen, on the monorail system, 

 invented by the late Mr. Eugen Langen of Cologne. 



The permanent way of this line consists of two girders supj)orted 

 either by arches or by " A " frames, and placed at such a level above the 

 street that the passenger carriages, hanging from wheels, which run 

 along the girders, are well above the traffic in the street. 



Ample precautions are adopted to prevent the wheels running off 

 the rails, and the current is taken by a trolley from a wire close to 

 the girder. The space between the girders is partly covered in so 

 that a footway is provided, which makes the trolley line and the 

 rails accessible at all times even when carriages are running. 



Getting in and out of the train, formed by a motor carriage and 

 trailers, is only possible at the stations, which resemble the ordinary 

 high level stations. 



For the greater part of its length the railway is suspended over 

 the river 'W'upper, and the slides clearly show that no beautiful 

 prospect is injured by the presence of the suj)erstructure over the 

 river. 



At the ends of the line and also at one intermediate station, 



