The encyclopedist Song Yingxing (1587–1666) documented a wide array of technologies, metallurgic and industrial processes in his "Tiangong Kaiwu" encyclopedia of 1637. This includes mechanical and hydraulic powered devices for agriculture and irrigation, nautical technology such as vessel types and snorkeling gear for pearl divers, the annual processes of sericulture and weaving with the loom, metallurgic processes such as the crucible technique and quenching, manufacturing processes such as for roasting iron pyrite in converting sulphide to oxide in sulfur used in gunpowder compositions – illustrating how ore was piled up with coal briquettes in an earthen furnace with a still-head that sent over sulfur as vapor that would solidify and crystallize – and the use of gunpowder weapons such as a naval mine ignited by use of a rip-cord and steel flint wheel.