Gun-boring machinery, Rio de Janeiro, Brazil, 1813.

Ink and wash drawing by W Warcup of a plant containing a steam engine and gun boring machinery manufactured by Henry Maudslay & Co, for a client in Rio de Janeiro in Brazil. Boring cannon barrels increased the accuracy of the guns as well as making them safer to use. John Wilkinson (1728-1808) patented a method of boring a hole in a solid piece of cast iron in 1774. Previously, cannon were cast as a single piece with a hole already in the middle. This often resulted in imperfections which meant the cannon was likely to explode on firing, with dire consequences for anyone nearby. Henry Maudslay (1771-1831) was an English precision toolmaker and engineer who invented the metal lathe in 1797.