Carbide lamps or acetylene gas lamps are simple lamps that produce and burn acetylene C 2 H 2 which is created by the reaction of calcium carbide CaC 2 with water H 2 O Acetylene gas lamps were used to illuminate buildings as lighthouse beacons and as headlights on motorcars and bicycles Portable acetylene gas lamps worn on the hat or carried by hand were widely used in mining