“What do you understand he meant by pointing to the _Bertha_ and then pointing east? It seemed to me that he wanted to inform us that he had seen a machine like that in that direction.” “It might have been the outlaw machine now chasing Jimmie,” suggested Ben. “He might have seen it before it passed over to the coast. It’s a wonder to me that he wouldn’t get out of the country after being trussed up by his own people.” “It’s just one of the mysteries of the case,” laughed Carl. “We don’t know anything about the Chinaman, or of Jimmie’s motive in going away, or of the smugglers!” The boys gathered up the remnants of the meal and sat down to wait for the return of their chum. They had remained seated only a short time when Carl called the other’s attention to the glistening planes of a flying machine away to the north and east. “There’s the Chink’s machine!” he exclaimed. Both boys sprang to their feet and Ben rushed to the _Bertha_ for a field glass. He looked steadily at the machine for a moment before speaking, then he handed the glass to Carl. “That’s certainly one of the largest aeroplanes I ever saw!” he cried. “I’ve seen big ones, but I never saw anything like that before! What do you make of it?” he continued as Carl lowered the glass. “I’ve been thinking,” the latter replied, “that it might be the _Ann_!” “If it is,” Ben answered, “she will miss us, for there she goes straight off toward San Francisco. She’ll miss us sure!” “Why don’t we get up in the air and chase her up?” asked Carl. “I was just thinking of that,” answered Ben, “but, you see, there’s Jimmie and Kit away, and they’d never be able to find us!” “Don’t you ever think they won’t be able to find us!” exclaimed Carl. “You can’t hide a flying machine the size of the _Bertha_ by taking it up in the air. First thing we know,” he continued, “we’ll have all four machines bunched. And then there’s likely to be a mix-up!” “Well,” Ben said, “if we’re going to start after that flying machine, we may as well be getting under way.” As will be remembered, the _Bertha_ had been overhauled early that very morning, and now it took only a moment to get her into the air. When she came to the lip of the valley the boys saw the large aeroplane sailing northward at great speed. Before Ben put on full power he turned to Carl with an anxious look on his face. “I shall have all I can attend to at the levers,” he said, “so you’ll have to keep watch for Jimmie and his outlaw escort. Keep your eye on the sky every minute of the time, and if you see two flying machines doing a Marathon, just give me a poke in the ribs with your elbow.” Carl nodded and Ben put on full speed, after which conversation was, of course, impossible.