SOUTII OF SAINT-GIRONS near the Spanish-French border is the deepest abyss in France, the Gouffre Martel. Its caverns twist for miles under the Pyrenees. It is the most formidable cavern hospital on Terra. No patient has ever jaunted out of its pitch darkness. No patient has ever succeeded in getting his bearings and learning the jaunte co-ordinates of the black hospital depths.