Abstract: Self-belaying apparatus. An apparatus for permitting sport climbing without the assistance of a belayer is described. While the user is climbing, the apparatus slides along the climbing rope with little resistance. Any downward motion is immediately stopped, however. When the climber wishes to continue ascending, the apparatus automatically releases its grip on the rope. The apparatus, which includes a base, an elongated bar, a flat plate and a pulley, can also be used for rapelling.

Abstract: A method for cutting with a laser beam where an oxygen-hydrocarbon reaction is used to provide auxiliary energy to a metal workpiece to supplement the energy supplied by the laser. Oxygen is supplied to the laser focus point on the workpiece by a nozzle through which the laser beam also passes. A liquid hydrocarbon is supplied by coating the workpiece along the cutting path with the hydrocarbon prior to laser irradiation or by spraying a stream of hydrocarbon through a nozzle aimed at a point on the cutting path which is just ahead of the focus point during irradiation.