Railway Electrical Engineer A.A. Stolpovsky became interested in telephony in 1882. He was an ardent supporter of the early introduction of telephony on rail transport. In 1884 he submitted a petition to the Department of Trade and Manufacture seeking privilege (patents were called privileges in pre-1917 Russia) to produce a phone with a ring-shaped pole, four magnets and a carbon microphone. The telephone invented by Stolpovskiy could transmit sound far enough, in excess of 700 miles. This was confirmed in an experiment between Moscow and Minsk.
In 1886, having received the privilege, A.A. Stolpovskiy teamed up with A. Kapger to create a telephone which was used for telephony on some railways.