They called him endearing names, which, so far as they could see, had not the least effect, but neither of them felt equal to entering the kitchen until Miss Oliver walked in by another door. Then the dog let her take the hat, wagging his tail with satisfaction. "He's a good deal more intelligent than you seem to think," she said. "Give him your hat, Harry, and then go out and wait for a few minutes before you come back for it." Harry did so, and the dog made no trouble when he picked up the hat, but he would not let Frank go near it in the meanwhile. After that they tried two or three more experiments of the same kind, though Frank took no part in them, which was a thing he regretted when he went for a swim an evening or two later. On this occasion the tide was almost full, the water in the cove was pleasantly warm and bright sunlight streamed down upon it, showing the white shingle a fathom beneath the surface. Now and then Frank went down toward it, for he had learned to swim under water and look about him while he did so, but by and by he headed for the entrance to the cove with the overhand side stroke which Harry had taught him. Swinging his left arm forward over his head, his face dipped under and then rose in the midst of a ripple as his hollowed palm swept backward under his crooked elbow to his thigh, while his legs swung across each other like a pair of scissors. The brine gleamed and sparkled as it slipped past him, and when he reached the entrance to the cove he slid up and down the smooth, green undulations with a pleasant lift and fall. It was so exhilarating that he went farther than he had intended, and he was feeling a little breathless when at last he turned back, but when he reached the spot where he had undressed trouble awaited him. The dog was seated upon his clothing, watching him with suspicious eyes, and it growled when he stood up knee-deep. Frank hesitated. The dog did not look amiable, but he was beginning to feel cold, and he walked slowly forward a pace or two. Then the creature raised itself on its forepaws, with white fangs bare, and once more broke into a deep, ominous growl. There was no doubt that it intended to guard his clothes.