Jonathan Crookes, a maker of ‘common’ pocket and penknives in Scotland Street, appeared (with his heart and pistol mark) in directories in 1774, 1787, and 1797. However, it was another Jonathan Crookes, who made that mark famous after the 1820s. This Jonathan was apparently baptised in 1788, the son of Marmaduke Crookes and his wife, Martha. Marmaduke was the son of Jonathan Crookes, who was a cutler (possibly the individual in Scotland Street). If this is correct – and the identi....