The short time that had elapsed since Tommy O'Doul gave the alarm had been minutes of swift preparation. What little of water, food and supplies could be brought into the cave had been hustled in by eager hands. The stock had been herded into the small, adjoining cave, and boulders had been rolled against the cave mouth. The metal grill had been dropped before the mouth of their own cave; it was behind this they now crouched, through this that Greg looked out upon a lead-gray sky and green hills. "There's one thing," said Greg. "One break in our favor. It's starting to get darker, and it's barely afternoon. We must be dipping into the penumbra of Saturn. In a little while the darkness should come, and the gales and the cold." Hannigan said, "That ain't no break for us. Marberry said they didn't feel heat and cold." "I know. But they can't prevent the snow falling. If it comes down like it did during the last dark spell, we will have an eight-foot fall of ice between us and our attackers." Andrews looked at the sky anxiously. "But until it snows, Greg?" "We fight!" said Greg grimly. Bert Andrews, who had wriggled forward on his belly to the furthermost ell of the bottle-neck, ducked back hastily, twisted his head over his shoulder. "Then we fight now!" he rasped. "Here they come!" It was then that the Earth-exiles saw, for the first time, the dominant race of Saturn's sixth satellite. To see was to marvel that Nature had once again--as on Earth, Mars, Uranus and Io--selected the bipedal humanoid form in creating a ruling race. Except for the thick, downy pelts that covered these Titanians' bodies, the low, slanting, bestial foreheads, the depth of breast and rapacious mouth slits, these creatures were the counterparts of man. But there were other unapparent differences, thought Greg. Marberry had reported the Titanians impervious to heat and cold, which argued a difference in normal body temperature and perhaps a difference in basic metabolism. There must be sharp differences between man's mentality and that of these man-like beasts, as well, else they would not come seeking their interplanetary guests as the huntsman seeks his quarry. A long, questing, silver-pelted line, they climbed the hillside path to the flat clearing before the cave. They paused there, peering about them suspiciously, nostrils wide and eyes searching. Greg realized, suddenly, that these man-things were far down humanity's scale; so much of the animal was in them that they placed more dependence in their olfactory than in their visual sense. They seemed to catch the man scent, the spoor they had been following. Their leader moved forward to the grillwork. Hannigan's shoulder brushed that of Greg as he wriggled forward. "Now, Greg? Shall we let 'em have it?" Greg whispered hurriedly, "When I give the word, all fire at once. Remember, we have very little ammunition. We must make every shot count. Ready?"