Long forgotten, from 1936, is Arthur ('A.L.M') Sowerby, the original author of this definitive text. It was 'revised and enlarged' by Marcus Graham ('M.G')Scroggie for the 1941 3rd Edition and, in recognition of its continued authority, is now in an updated 11th edition and bearing Scroggie's name in homage.
It has lost none of its detail and has been faithfully updated to accommodate the changing world of electronics. It keeps the mathematics to a minimum and seeks to explain by reference to useful examples. It continues to be an authoritative work.