The superiority of a horizontal over a triangular arrangement of conductors is viewed from a new angle and the reasons for adopting a horizontal arrangement on wood poles for 260 miles of 110 kV. Loadings are compared with those specified by the British Regulations for Overhead Lines, and the effectiveness of the universal method of controlling the factor of safety of conductors is challenged. The factors governing the examination of breakdown data are analyzed critically and the data and conclusions for particular cases are stated briefly. Burke gives particulars of some of the serious damage caused by snowstorms to electrical transmission lines in Ireland, and of consequent departures from conventional design.

IN a paper with this title read in London on December 9 before the Institution of Electrical Engineers, Mr.