1. A torch comprising a torch body having a longitudinal axis and a tip; a sensor mounted to said torch body for establishing the relative positions of said tip of said torch body and an object radially disposed relative to said longitudinal axis, said sensor comprising: (a) an annular sensing body surrounding said tip of said torch body so that said torch body extends through said sensing body, said sensing body being radially displaceable relative to said tip upon contacting an object radially disposed relative to said tip of said torch at any point about the periphery of said tip; (b) connecting means mounted to said sensing body to be angularly displaced with respect to said longitudinal axis in a direction and to an extent directly corresponding to the displacement of said sensing body; (c) means for continuously detecting the angular displacement of said connecting means and generating a signal directly corresponding to said angular displacement; and means for receiving said signal and continuously positioning said torch body in a direction and to an extent directly corresponding to said signal.