From the end of 16 to the end of 17, the British mining industry, especially coal mines, has developed to a considerable scale, and it is difficult to meet the requirements of pumping groundwater only by manpower and animal power, and there are abundant and cheap coal as fuel on site. The needs of reality have prompted many people in Britain, such as Papan, savery and newcomen, to devote themselves to the exploration and experiment of "lifting water by firepower".
1764, British instrument repairman Watt noticed this shortcoming when repairing the newcomen steam engine model for Glasgow University, and invented the steam engine with the condenser separated from the cylinder wall in 1765, and obtained the British patent in 1769. In the early days, Watt's steam engine still used the balance bar and pull rod mechanism to drive the water pump. In order to remove the condensate and air from the condenser, Watt installed an air pump. He also installed an interlayer on the outer wall of the cylinder and heated the cylinder wall with steam to reduce condensation loss.