Britain's most spectacular commemoratives, No71: 1976 Social Reformers 11p

One of David Gentleman’s best pieces of design was the set of four honouring champions of reform in the spheres of factory exploitation, child labour, trade unionism and prison conditions.

Dark-hued and bleak, and cleverly showing hands set in very adverse situations, each stamp sums up in an instant what the problem was.

The 11p value highlights the cruel Victorian use of child chimney sweeps, evoking the soot-polluted environment of narrow, jagged, crumbling brickwork through which small boys were forced to crawl.

It was Anthony Ashley-Cooper, the 7th Earl of Shaftesbury, who brought about the abolition of this practice, one of many humanitarian reforms he led.

Design: David Gentleman.
Printing: gravure by Harrisons.