Number 72 (Story #4), March 23, 1992 by Phillip F. Schewe and Ben Stein THE TOKAMAK PHYSICS EXPERIMENT (TPX) may become the next principal magnetic-confinement fusion device now that plans for the $1.8-billion Burning Plasma Experiment (BPX) have been dropped. The $400-million TPX would not reach ignition temperatures or densities (which were planned for PBX), but would aim to sustain 1000-second plasma burning periods. (Science, 6 Mar. 1992.)