For two hundred feet the grassy sward was bathed in moonlight. They could not walk across it without being in full view of any one who might be watching from the mill. But it had to be crossed as the mill itself was isolated on the bank of the river and on this side there was no protecting shade to enable them to creep up closer. "We'll have to crawl across the grass," Frank whispered. "Ready?" "I'm ready." "Go easy and quiet. If you hear a sound, don't move." They dropped to their hands and knees, then left the shadow of the wood. They began to crawl slowly toward the willow tree at the rear of the mill. Inch by inch they made their way forward. The moon was high in the sky and seemed like a giant searchlight. It seemed impossible that they could cross that open space without being discovered. Every blade of grass seemed clearly revealed by the moonlight. When they were about half way toward the mill they heard a sound in the distance. It was the banging of a heavy door. There was a warning whisper from Frank. They lay motionless in the thick grass. For a moment a deep silence prevailed. Then, from the mill, they heard a surly voice: "I saw some one out on the hillside." They were startled. But still they did not move. Their only hope of safety lay in silence and in remaining motionless. "You're crazy, Markel," replied some one. "There's no one out there." "I tell you I saw some one crawling down through the grass. I'm sure of it. I saw him from that upper window." "Whereabouts?" "Out there--see? Can't you see something dark up there?" There was silence for a moment or so. Then the second man laughed. "It's only a log." "I tell you, it isn't a log. A log doesn't move." "That isn't moving." "It was." "Well, if you're so sure of it, why don't you go on up and see? You're getting so nervous lately that you think people are hanging around here all the time." "I've got a right to be nervous. We're not safe here, I tell you. We should have moved out of here a week ago." "We'll never find a place as safe as this." "Is that so? Ever since those two boys came snooping around here and asking Lester questions I've been suspicious. They've got their eye on this place, let me tell you. They were down at the railway station the day I slipped the package to Burgess, and I'm mighty sure they saw me." "Just a couple of kids. You're too nervous." "Well, I'm going up on the hill and take a look at that log, as you call it." As it happened, there was a log lying in the grass close by Frank. But he realized that if Markel came up to investigate he would have no chance to evade discovery. They could not get up and run away--at least not until capture seemed inevitable. Frank's heart sank. They had been discovered before they had a chance even to reach the mill. At that moment relief came from a most unexpected quarter.