Casgliadau Arlein

British Transport Commission, Mech & Elec Engrs. Department, South Wales Docks, revised single line diagram of 11, 6.6 and 3.3 KV electricity supplies at Port Talbot. Drawing number 8579. Letter with diagram addressed to E.R. Radway, Mechanical & Electrical Engineer of British Transport Commission, Cardiff from E. Sutton, H.M. Electrical Inspector of Factories. Letter relates to the diagram, dated 12 April, 1954. Hand drawn diagram printed in black on cream paper.