Blow-pipe

(blo'-plp). A cylindrical tube, from twelve to eighteen inches long, about half an inch in diameter at one end, and gradually tapering to a fine point or nozzle, which may be straight or bent at a right angle; it is used in directing the flame of a lamp in a fine conical tongue. B., Automaton, in dentistry, a blow-pipe especially designed for crown and bridgework, into which the air is admitted and conducted through a small tube to the upper end of another which admits illuminating gas. The supply of both air and gas is regulated by the pre sure of the thumb or fingers on the rubber tubes of the appliance. B., Oxyhydrogen, an apparatus for producing intense heat by burning hydrogen or illuminating gas at the end of a mixing nozzle.