Shandon looked in a northerly direction, and shuddered in spite of himself. A strange animal, with appalling movements, whose foaming tongue emerged from enormous jaws, was leaping about at a cable's length from the ship. In appearance he seemed to be about twenty feet high, with hair like bristles; he was following up the sailors, whilst his formidable tail, ten feet long, was sweeping the snow and throwing it up in thick whirlwinds. The sight of such a monster riveted the most daring to the spot. "It's a bear!" said one. "It's the Gevaudan beast!" "It's the lion of the Apocalypse!" Shandon ran to his cabin for a gun he always kept loaded. The doctor armed himself, and held himself in readiness to fire upon an animal which, by its dimensions, recalled the antediluvian quadrupeds. He neared the ship in immense leaps; Shandon and the doctor fired at the same time, when, suddenly, the report of their firearms, shaking the atmospheric stratum, produced an unexpected effect. The doctor looked attentively, and burst out laughing. "It's the refraction!" he exclaimed. "Only the refraction!" repeated Shandon. But a fearful exclamation from the crew interrupted them. "The dog!" said Clifton. "The dog, captain!" repeated all his comrades. "Himself!" cried Pen; "always that cursed brute." They were not mistaken--it was the dog. Having got loose from his shackles, he had regained the surface by another crevice. At that instant the refraction, through a phenomenon common to these latitudes, caused him to appear under formidable dimensions, which the shaking of the air had dispersed; but the vexatious effect was none the less produced upon the minds of the sailors, who were very little disposed to admit an explanation of the fact by purely physical reasons. The adventure of the Devil's Thumb, the reappearance of the dog under such fantastic circumstances, gave the finishing touch to their mental faculties, and murmurs broke out on all sides. CHAPTER XII CAPTAIN HATTERAS The _Forward_, under steam, rapidly made its way between the ice-mountains and the icebergs. Johnson was at the wheel. Shandon, with his snow spectacles, was examining the horizon, but his joy was of short duration, for he soon discovered that the passage ended in a circus of mountains. However, he preferred going on, in spite of the difficulty, to going back. The dog followed the brig at a long distance, running along the plain, but if he lagged too far behind a singular whistle could be distinguished, which he immediately obeyed. The first time this whistle was heard the sailors looked round about them; they were alone on deck all together, and no stranger was to be seen; and yet the whistle was again heard from time to time. Clifton was the first alarmed. "Do you hear?" said he. "Just look how that animal answers when he hears the whistle." "I can scarcely believe my eyes," answered Gripper. "It's all over!" cried Pen. "I don't go any further."