* * * * * Much later Rolf groaned with the pain of bruised muscles and tried to rise. To his amazement he could move all his limbs. Carefully he came to his knees and so to his feet. Not a bone was broken, unless the sharp breathlessness that strained at his chest meant cracked ribs. There was light in the narrow pit in which he found himself, light and heat from the yet-glowing debris of the rocket flyer. The outlaws had blasted the crashed ship, his practiced eyes told him, and Garmon Nash must have died in the wreckage. He was alone in the waterless trap of a deep crevice. In the fading glow of the super-heated metal the vertical walls above mocked him. There could be no ascent from this natural prison-pit, and even if there were he could never hope to reach the surface forty miles and more overhead. The floors of the thirty-seven caves through which they had so carefully jetted were a splintered, creviced series of canyon-like wastes, and as he ascended the rarefied atmosphere of the higher levels would spell death. Rolf laughed. Without a pressure mask on the surface of Mars an Earthman was licked. Without water and food certain death grinned in his face, for beyond the sand-buried entrance to these lost equatorial caves there were no pressure domes for hundreds of miles. Here at least the air was thick enough to support life, and somewhere nearby the outlaws who smuggled their precious contraband water into the water-starved domes of North Mars lay hidden. The young patrolman unzippered his jacket pocket and felt for the emergency concentrate bars that were standard equipment. Half of the oval bar he crushed between his teeth, and when the concentrated energy flooded into his muscles he set off around the irregular wall of the pit. He found the opening less than ten paces from the starting point, an empty cavity higher than a man and half as wide. The glow from the gutted ship was failing and he felt for the solar torch that hugged flatly against his hip. He uncapped the torch and the miniature sun glowed redly from its lensed prison to reveal the rocky corridor stretching out ahead. * * * * * Light! How many hours later it was when the first faint glow of white light reached his eyes Rolf did not know--it had seemed an eternity of endless plodding along that smooth-floored descending tunnel. Rolf capped the solar torch. No use wasting the captive energy needlessly he reasoned. And he loosened the expoder in its holster as he moved carefully forward. The outlaw headquarters might be close ahead, headquarters where renegade Frogs, Venusians from the southern sunken marshes of Mars, and Earthmen from dusty North Mars, concealed their precious hoard of water from the thirsty colonists of North Mars.