Dave walked on and on along the lake shore, paying little attention to where he was going. His mind was in a state bordering on bewilderment. In a faint, uncertain way he had anticipated some such calamity, but now that the blow had fallen, the matter looked almost hopeless to him. Had he followed his own inclinations, he would have made preparations to return to Crumville at once. "But evidently they don't want me there," he told himself, bitterly. "They want to solve this mystery without my interference. And if they do make up their minds that I am not the real Dave Porter, I wonder how they will treat me? Of course, they may be very kind to me--the same as Laura and Jessie and the others up here. But kindness of that sort isn't everything. I don't want any one to support me if I haven't some claim on him." And then Dave shut his teeth hard, clenched his hands, and walked on faster than ever. Finally tired out because he had been on his feet since early morning, Dave sat down on a flat rock to rest. As he did this, he heard the put-put of a motor, and presently around a bend of the shore showed the headlight of Mr. Appleby's motor-boat. "I wonder if they are simply going down to the end of the lake, or whether they are going to stop at our place," said Dave, to himself. "I'd rather they wouldn't stop at Bear Camp to-night, when everything is so upset." As the motor-boat swung around, the headlight flashed full upon our hero and there followed an exclamation from the manager of the moving-picture company, who was at the wheel of the craft, with two men beside him. "Hello there, Porter! What are you doing--fishing?" "No, I just came down here to sit on the rock and do a little thinking," answered Dave. "We are making a little trip around the lake," went on Mr. Appleby. "I was going to stop at your dock and deliver a letter that came in our mail by mistake. It's a letter for you, so I might as well give it to you now." "A letter for me, eh?" answered Dave. "Yes, here you are!" went on Mr. Appleby, as the motor-boat came to a standstill close by. "I'll put it in the newspaper and you can have that too, as we have read it;" and suiting the action to the word, the man placed the letter in the folds of the paper and tossed the latter ashore. "Will you stop?" questioned Dave. "Not to-night. We are going to make a call on the other side of the lake. I just thought I'd give you the letter, that's all," and then, with a pleasant good-bye, the manager steered his motor-boat out into Mirror Lake again. It was too dark to read the letter without a light, and as Dave did not happen to have even a match, he walked back to the bungalows. The lanterns were hung out on the porches as was the custom, and under the light of one of these he looked at the communication he had received.