about two mile, there's a little shack up there where he telephones back to the Station to show he's on the job, and he punches his own clock. It takes him about two hours to get up there and back, and when he gets in, why he takes the watch in the Station, and the other feller takes the beach-patrol in the opposite direction, down the shore. See, ma'am?" Joan did.
"Well, then," said the captain, "you see that if them Germans caught them fellers just at the beginning of their watch, and knocked 'em both out, they'd have a full four hours to do their dirty tricks in, and nobody'd be none the wiser till 't was time to change the watch. And it ain't been but three hours since them boys went on their watch."
Joan understood the explanation, but she was too tired to answer the captain's vigorous comments on the spies' plot and German treachery in general. The nearer she drew to Silver Shoal, the more her thoughts were of Garth, and of Garth only. What if something had happened during this time? Calmer reasoning could not check her growing fear. Would the boat never, never reach the lighthouse? To her weary brain the lamp which shone across the water seemed now a great formless flame burn-
