'Petards, Partridges, and Infernals', 1798.
© Science Museum / Science & Society Picture Library
Engraving by J Chapman showing different types of artillery. A petard is a small bomb, seen here (top and bottom right) being used to blow apart the door to a fortress. A partridge was a charge for cannons consisting of several missiles fired together, seen here (top left) with a sectioned diagram. An infernal machine was a device for producing an explosion; this may be what the illustration in the centre of the page is showing. Illustration from 'Encyclopaedia Londinensis, or, Universal Dictionary of Arts, Sciences, and Literature' published in London, 1810-1829.