National Rail Museum

The most elegantly streamlined of all British Rail’s steam locomotives was the Great North Eastern Region A4 class of which an engine called Mallard is the best known of the 35 built at Doncaster works. Designed in 1935 by Sir Nigel Gresley, whose earlier A3 class (of which Flying Scotsman is the preserved example) was in terms of classy looks arguably the apogee of the conventional un-streamlined locomotive, the A4s, or Streaks as trainspotters dubbed them, pulled blue riband expresses between King’s Cross and Edinburgh/Aberdeen. Few who have seen one will forget it because they represent the most dashing solution to their function. In terms of efficiency (especially if fuelled by the best Welsh coal) it was as reliable and as quick as Charles Collett’s ‘King’ class of the Great Western Railway, though far racier on the eye.

Often over the 13 years of The Jackdaw an argument has been advanced that as a work of sculpture, of form, of beautiful workmanship, an A4 (or, indeed, a Collett ten-wheeler or a Stanier pacific) is immeasurably more stimulating