Many thanks to Martin Cummins for turning up these British Telegraph Pole related Patents. In his untiring search for information about the little metal ducts that run up the side of many telegraph and DP poles, Martin found these which may be of interest to our readership. All can easily be viewed by using espacenet advanced (gb). Once on the worldwide site, just inserting gb followed directly by the number, will reveal all.
http://www.ipo.gov.uk/espacenet.htm
GB1561291, GB2006317, GB2121080: All relate to the clever system of connecting up subscribers at ground level, though the last refers to using stayed fibreglass, which I am not sure were used.
GB2221935: Neat BT way of changing pole without interrupting service.
GB770918: Early method for rot-proofing pole.
GB2327057 Clever wrench for turning pole without raising splinters.
GB191024483, GB342786: Early pole incising machines.
GB1310781, GB1410879: later incisers.
US1573143, US1621963, US1992057, US2563758, US3515184, US3709271: A few incising machines from the States – They are keen on this treatment, presumably because of the conditions.