He sat by the window for some little time. Then, first putting on a pair of rubber-soled tennis shoes, and taking with him the stick he had brought from Frattenbury, first unwrapping it from its brown paper covering, he slipped quietly downstairs and went out. Very carefully picking his way, he went down to the shore. It was a perfectly quiet night, the silence only broken by the ripple of the tide flowing up the estuary. He looked around him. Only one light was burning—in a window of Mr. Proctor’s house. The latter had evidently not yet gone to bed. Colson unhitched the painter from the post, slowly, without making a sound, launched the canoe, and paddled out in silence. Arrived beside the dinghy, he placed the walking-stick well under the seat, where he had found the original, and returned just as quietly to the shore. Before he went back to the inn he took careful stock of another canoe that was close to the shore, and gave a nod of satisfaction. Then he returned to his room and waited and watched. As he had said, it was a forlorn hope and he hardly expected that anything would come of it. It was more than probable that the murderer was miles away by this time. And yet, if that stick _had_ belonged to him, so far as Colson knew at present, it was the only clue to the mystery. And whoever had left it in the dinghy must know that as well. The point that Colson was building upon was the fact that the stick had been stowed away under the seat of the dinghy and was not found on board the yacht itself. If it belonged to the man who had committed the crime, there was just the chance that he might calculate that little notice had been taken of the dinghy. And it would be worth something to him to get it back. It was some time after midnight that Colson gave a start and stood tense at the window. A slight sound had disturbed him. Straining his eyes through the darkness, he could just discern a form apparently bending over one of the canoes on the shore. Then he saw the form straighten itself and walk a little distance away. He lost sight of it, but in a few moments it returned. Again it bent down. “He’s unfastening the painter,” murmured the detective. Then he could see a man get into the canoe, and the next moment he could hear the slight splash of a paddle. The unknown was making for the yacht. Colson felt the little automatic pistol he carried in his pocket—he was taking no risks. Quickly he made his way downstairs, opened the door and went out, crouching low. It was his intention to get down to the shore, lie hidden behind one of the boats, and catch the unknown unawares as he landed. He looked across the water. The canoe was alongside the dinghy now. He had to act quickly to get to his hiding-place.