22 SEPTEMBER 1923, Page 3

Some carriages are slowing down while others are accelerating. This

mechanical feat is achieved by means of a revolving spiral which is laid between the tracks and is carried on spokes projecting from a steel tube. Under- neath each carriage is an arm with two vertical rollers which engage with the spiral. At the stations the pita of the spiral is very fine—result, slow speed. Between the stations the pitch is very coarse—result, fast speed. It has been shown that it is possible to pass from a slow speed to a high one quite smoothly. The station on the demonstration ground is never without one or more carriages passing slowly through it. Moreover, the station is divided into two parts ; at one part people get into the carriages, and at the other they alight, so that there can be no confusion.