This paper contains materials of second paragraph of unreleased manuscript «Development of Signaling, Interlocking and Line-Block on Russian Railways» written by the fi rst head of «Automation and Remote Control on Railways» department of Leningrad institute of railway engineers Nikolay Vasilyevich Lupal. It describes features of train traffi c control on open lines during considered period.
train traffic, open line, semaphore, electric detaining mechanism, electromagnet telegraph, automatic line block, electric rod system