Elementary telegraphy : a manual for students; written specially to meet the requirements of the ordinary grade of the subject as published in the syllabus of the city and guilds of London Institute (1910)
Pendry, H. W. (Henry Walter) · London ; New York : Whittaker & Co. · leaf 145
frequentlyemployed on very heavy lineswhere provision has to bemade for a large number ofwires and in situations wherethe conditions demand a poleof considerable strength. Asshown in Fig. Ill, this struc-ture consists of two similarpoles erected 18 inches apartand braced together by asystem of… … \ Fig. 111.—H pole. Fio. 112.—Iron polewithifoot plate. TELEGRAPH LTNES 185 against, lateral displacement is nlitained by means (if kickingblocks placed at right-angles to the ends of the timberbrace, the lower block being placed on the inside of thecurve. The triissiiig consists of horizontal tie…
Telegraph
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