The tree up which they had clambered was the largest of the group and of dense foliage. It was one of the huge conifers of the age, but its branches extended to within perhaps thirty feet of the ground, and from the greatest of these side branches reached out, growing so close together as to make almost a platform. It was but the work of a half hour for these boys, with their arboreal gifts, to twine additional limbs together and to construct for themselves a solid nest and lookout where they might rest at ease, at a distance above the greatest leap of any beast existing. In this nest they curled themselves down and, after much clucking debate, formulated their plan of operation. Only one boy should dig at a time, the other must remain in the nest as a lookout. Swift to act in those days were men, because necessity had made it a habit to them, and swifter still, as a matter of course, were impulsive boys. Their tree nest fairly made, work, they decided, must begin at once. The only point to be determined upon was regarding the location of the pit. There was a tempting spread of green herbage some hundred feet to the north and east of the tree, a place where the grass was high but not so high as it was elsewhere. It had been grazed already by the wandering horses and it was likely that they would visit the tempting area again. There, it was finally settled, should the pit be dug. It was quite a distance from the tree, but the increased chances of securing a wild horse by making the pit in that particular place more than offset, in the estimation of the boys, the added danger of a longer run for safety in an emergency. The only question remaining was as to who should do the first digging and who be the first lookout? There was a violent debate upon this subject. "I will go and dig and you shall keep watch," said Oak. "No, I'll dig and you shall watch," was Ab's response. "I can run faster than you." Oak hesitated and was reluctant. He was sturdy, this young gentleman, but Ab possessed, somehow, the mastering spirit. It was settled finally that Ab should dig and Oak should watch. And so Ab slid down the tree, clamshell in hand, and began laboring vigorously at the spot agreed upon. It was not a difficult task for a strong boy to cut through tough grass roots with the keen edge of the clamshell. He outlined roughly and rapidly the boundaries of the pit to be dug and then began chopping out sods just as the workman preparing to garnish some park or lawn begins his work to-day. Meanwhile, Oak, all eyes, was peering in every direction. His place was one of great responsibility, and he recognized the fact. It was a tremendous moment for the youngsters. CHAPTER VI. A DANGEROUS VISITOR.