Hauling and rebaiting the hundred-odd traps was a good five hours' job and more for the couple, neither of whom had ever handled a small boat or seen a live lobster before the previous month. As the forenoon advanced the air seemed to grow thicker and more breathless. Over the water brooded a languid haze, through which the sun rays burned with a moist, intense heat. Percy's bare arms began to grow red and painful. "Feel as if they were being scalded," he complained. "I've heard Jim say a fog-burn was worse than any other kind. Now I know he's right." Eleven o'clock, and still twenty-five traps to be pulled. Most of these were on the Dog and Pups, a group of ledges more than a mile northeast of the island. It was the best spot for lobsters anywhere about Tarpaulin. Percy hesitated. "Fog seems to be closing in a little," he observed, "and we haven't any compass. Should hate to get out there and have it shut down thick. Might be hard work to find the island again." He glanced at the tub of lobsters. "If the Dog and Pups keep up anywhere near their average, we'll beat the record. What d'you say, Filippo? Shall we take a chance and surprise the rest of 'em?" Filippo flashed his white teeth. "I go with you," he smiled. "Then go it is!" decided Percy. He headed the pea-pod for the Dog and Pups. "We'll keep a sharp lookout, and if it starts to grow anyways thick we'll strike back for old Tarpaulin." A pull of about twenty minutes brought them to the ledges, around which the traps were set in a circle. They began hauling at the point in the circumference nearest to the island, following the buoys west and north. The catch exceeded their hopes. "We'll need another tub, if this keeps up," chuckled Percy. Filippo laughed jubilantly. The fog was forgotten. Their entire attention was centered on the contents of each trap as it was pulled. Round on the edge of the circle farthest from the island a pot refused to leave bottom. Percy tugged till he was red in the face, but he could not start it. "Catch hold with me, Filippo!" he puffed. The Italian joined his strength to Percy's, but to no avail. The slacker still clung to the bottom. The boys straightened up, panting. "We'll have to leave it," acknowledged Percy, disappointedly. "Probably there's half a dozen two-pound lobsters in it." He looked about and gave a startled cry. "Where's the island?" The wooded bluffs of Tarpaulin had disappeared. While they had been wrestling with the stubborn trap the fog had stolen a march on them. On all sides loomed a horizon of gray mist, not a half-mile distant and steadily drawing nearer. They must locate the island and get back to it at once. Percy tossed over the buoy and the warp at which they had been pulling. Tarpaulin lay southwest; but which way was southwest? Busied with the trap, he had utterly lost all sense of direction. The sun? He glanced hopefully up. No; that would not help any. The fog was too dense. Ha! The surf?