John Theophilus Desaguliers, a British engineer, demonstrated the successful use of a fan system to draw out stagnant air from coal mines in 1727—ventilation was particularly important in coal mines to prevent asphyxiation—and soon afterwards he installed a similar apparatus in Parliament. The civil engineer John Smeaton, and later John Buddle installed reciprocating air pumps in the mines in the North of England, though the machinery was liable to breaking down.