Further information from J Thickitt: The identification of this diesel's class (class 20) is anachronistic; British Rail's diesel fleet was re-numbered, also acquiring a number to identify each class (as here) in the early-1970s.

Numbered in the D8000 series, at the date of the photograph this class of diesel was known as the 'English Electric Type 1'. The description Type identified their (modest) power rating (so modest, that within a few years members of this class could often be seen working in pairs on coal trains (see s42763)

These new English Electric Class (Bo_Bo) locomotives were being allocated to depots in the Sheffield area on an almost weekly basis around this period, and the shiny new one depicted here contrasts starkly against the filthy unidentifiable Stanier 8F. Set against the background of Cammell Laird's Carlisle Street works.

Bo-Bo was a technical description of this English Electric Type 1's wheel arrangement.

An observation on the term the old Stanier 8F ... For steam locomotives the description old referred more to such as the 'Johnson 3F' (a03611). William Stanier's 8F class, introduced in the 1930s, were successful and therefore popular with their crews; this engine was in-steam so still needed, as some were until the end of British Rail steam in 1968.

A former Grimesthorpe engine-driver familiar with this class reminisced that the 8F's were good for the heavy stuff .