"Get busy, girls," called Grace. The Overlanders, dismounting, inhaled deeply of the air, heavily pungent with the odor of the pine, then set to work with a vim to pitch their camp. Tom, in the meantime, climbed the bank to look at a huge pile of logs that lay on a skidway above their camping place. "Someone got left last spring," he said upon his return to his companions. "Those logs were cut last winter, but the water in the river last spring was evidently too low to float them down, so they must stay where they are until next spring awaiting the freshets. The blocks will then be knocked from under the skidway and those hundreds of thousands of feet of timber will go thundering down into the river. You will observe that they have cut a channel or 'travoy,' as it is called, through which the logs will roll after leaving the skidway, and pass on to the stream. This 'travoy' is pretty well grown over with second growth, but the logs will roll the growth down, and when they do you would think that all the tremendous forces of nature had been let loose." By this time the camp was nearly finished, and the tents of the Overlanders looked like tiny doll houses under those giant pines, and in this, the very heart of nature, in the silence and the grandeur of it all, the girls felt a deep sense of something that they could not define, which left them disinclined to laugh or chatter. Soon after dark the sky became overcast, the pines began dripping moisture, and a gentle breeze was heard murmuring in the tops of the trees. "Come, little nature child! What are the wild winds in the tree-tops saying?" teased Hippy, breaking an awed silence of several minutes. "I--I don't rightly know," answered Emma, after listening intently to the whisperings in the pines. "I--I think that the message they are trying to convey to me--to us--is a warning of something to come, something that is near at hand. I wish Madam Gersdorff were here. She could read the warning and tell us what peril it is that is hovering over us." Nora uttered a shrill peal of laughter. "Don't," begged Anne. "You've got a bad attack of the willies," groaned Hippy in a tone of disgust that brought a half-hearted laugh from his companions, though, had they been willing to admit it, they too felt something of the depression that was reflected in Emma Dean's face and voice. Work on the camp finished, the Overland Riders put out the fire and turned in, Henry rolling himself up into a furry ball, Hindenburg snuggling down between Tom and Hippy. Only forest sounds, now faint and far away, marred the solemn impressive stillness of the Big North Woods, a stillness that was destined to be rudely interrupted ere the dawn of another day. CHAPTER VII FELLED BY A MYSTERIOUS BLOW