Signals and interlocking development during imperialism (1906-1917). Part 4: Safety devices
The study in question contains the materials of the third part of an unpublished monography manuscript «The development of signaling arrangement on Russian railroads» written by Nikolay Vasiliyevich Lupal, the ﬁrst head of «Automatics and telemechanics on railroads» chair at Leningrad institute of railway engineers. The issues of train safe control at the stations, equipped with mechanical interlocking were touched upon in the given study.