At first they hadn’t even known that the Sack existed. If they had noticed it at all when they landed on the asteroid, they thought of it merely as one more outpost of rock on the barren expanse of roughly ellipsoidal silicate surface, which Captain Ganko noticed had major and minor axes roughly three and two miles in diameter, respectively. It would never have entered anyone’s mind that the unimpressive object they had unconsciously acquired would soon be regarded as the most valuable prize in the system.
The landing had been accidental. The government patrol ship had been limping along, and now it had settled down for repairs, which would take a good seventy hours. Fortunately, they had plenty of air, and their recirculation system worked to perfection. Food was in somewhat short supply, but it didn’t worry them, for they knew that they could always tighten their belts and do without full rations for a few days. The loss of water that had resulted from a leak in the storage tanks, however, was a more serious matter. It occupied a good part of their conversation during the next fifty hours.
Captain Ganko said finally, “There’s no use talking, it won’t be enough. And there are no supply stations close enough at hand to be of any use. We’ll have to radio ahead and hope that they can get a rescue ship to us with a reserve supply.”
The helmet mike of his next in command seemed to droop. “It’ll be too bad if we miss each other in space, Captain.”
Captain Ganko laughed unhappily. “It certainly will. In that case we’ll have a chance to see how we can stand a little dehydration.”
For a time nobody said anything. At last, however, the second mate suggested, “There might be water somewhere on the asteroid, sir.”
“Here? How in Pluto would it stick, with a gravity that isn’t even strong enough to hold loose rocks? And where the devil would it be?”
“To answer the first question first, it would be retained as water of crystallization,” replied a soft liquid voice that seemed to penetrate his spacesuit and come from behind him. “To answer the second question, it is half a dozen feet below the surface, and can easily be reached by digging.”
They had all swiveled around at the first words. But no one was in sight in the direction from which the words seemed to come. Captain Ganko frowned, and his eyes narrowed dangerously. “We don’t happen to have a practical joker with us, do we?” he asked mildly.
“You do not,” replied the voice.