The description continues in meticulous detail, observing that with the action of the piston, 'the oil comes out through the ignition-chamber and is shot forth as blazing flame.' Needham has reconstructed the details of the mechanical operation of the flame-thrower and concluded that it had 'two of the tubes secretly connected within the tank. Such a design is very compatible with the directions in the text that the machine was to be started with the piston-rod pushed fully forward, and it also agrees with the statement that the "two" communicating feed tubes are alternately occluded.' The flame-thrower gave a continuous jet of flame 'just as the double-acting piston bellows gave a continuous blast of air, and the most obvious way of effecting this was to have a pair of internal nozzles one of which was fed from the rear compartment on the backstroke'.

A Chinese flame- thrower in action. Gunpowder-impregnated fuses for flame-throwers were the first use of gunpowder in warfare, before it was made with sufficient saltpeter to enable it to explode.

An illustration of a Chinese flame-thrower, published in 160 1, redrawn from an encylopedia of 1044. The Chinese invented the continuous flame- thrower in the tenth century, having known of the seventh-century spurting flame-thrower of the Byzantines via Central Asia. Here we see the tank standing on four feet, with the pump and ejector above it. Because the Chinese invention of a double-acting Piston-bellows was used with this device, a continuous stream of flame could be emitted. The metal used was cartridge-quality brass.