Mid-point

The traction motors are connected in three parallel groups of two in series, and the mid-points of each pair of motors are connected together; the mid-point connection is used in conjunction with relays to form a device which is sensitive to wheelslip, thus leading to an improvement in adhesion.

Published on March 27 1963, and subsequently known as the 'Beeching report' after its infamous author, the document represents a mid-point in the evolution of Britain's railway network - from one ravaged by wartime neglect into the system we recognise today.