Out in the yard the two boys held a hasty confabulation. They felt that they must act quickly. It was their duty to protect their mother's property from this Hun robber. The situation appealed to their boyish instincts. David's eyes gleamed with a wrathful twinkle. Anthony's young fists were tightly clenched. They laid a careful plan of campaign, then started off to secure recruits. In ten minutes they returned from the village with three Boy Scouts, to whom they unfolded their designs. They hurried off at once to the island, to survey the scene of action. The barrier which Mrs. Watson had caused to be erected across the brook, was constructed of two stout poles with withies intertwined; the ends were secured in the banks, and there was room for the water, even in flood, to flow underneath. On the Walden side of the stream were some large stepping-stones, which the joiners had placed for their convenience when fixing the posts into the overhanging bank. David and Anthony, with their scout friends, took off boots and stockings, and after a considerable amount of shoving and splashing, managed to move away the small stones that supported these boulders, leaving them apparently safe, but in reality only lightly balanced in the brook. They had barely finished when twilight began to fall. "We'll clear out now!" commanded David. "He may come any minute, and I want him to be hard at work before we appear on the scenes. We'll catch him red-handed." "And give him more than he expects!" chuckled Anthony. Going back to the house, the boys took Avelyn into their confidence. They felt that it would be mean to leave her out of such a thrilling adventure. "If you're game to come, you can," they allowed graciously. "It ought to be a sporty job!" "Blossomy!" agreed Avelyn. "I wouldn't miss it for worlds. But what about Pamela? She'd enjoy it, of course, but her uncle would know she'd given the show away." "She must hide behind the bushes, and not let him see her. It'll be top-hole for Pamela!" The alders and clumps of furze were thick down by the stream, quite sufficient to give shelter to the little party of seven that presently took cover there. They preserved strict military discipline. Not a word was spoken. All crouched silently watching and waiting. The sun had set, and the red glow faded from the sky, but there was a young moon, and objects were clear. David held Billy by the collar. He was a sporting dog, and trained not to bark; though he panted and his eyes bulged, he did not betray the whereabouts of his owner by even the suspicion of a yelp. Early experience with a former master, addicted to poaching, had taught him his lesson.