The younger lad bade his friend good-night and imitated the action of Hank Hazletine, wrapping his blanket around himself and lying down near the fire. He was not quite so prompt in sinking into slumber, but it was not long before Jack Dudley was the only one of the little party in command of his senses.
Jack, like his companions, felt the need of sleep, but the fact that he had but a brief while to remain awake, and the consciousness that the safety of others, as well as his own, rested upon himself, made him very alert. He believed he could sit or recline on the ground and retain his wits, but, fortunately, he had too much prudence to run that risk. Sleep is so insidious a foe that we can never recall the moment when it overmasters us, nor can we fight it off when in a prone or easy posture.
He adhered to the plan he had formed. Winchester in hand, he moved away from the fire until, by interposing the large trunk of a tree between himself and the light, he was invisible from that direction. He stood erect, taking care not to lean against the trunk for partial support, and concentrated his faculties into those of listening and looking.
The stillness was profound. From the distant mountains to the westward came a low, soft, almost inaudible murmur, such as one hears when many miles from the calm ocean, and which has been called the voice of silence itself. In the stillness he heard the faint crackle of one of the embers as it fell apart, and, though the night wind scarcely stirred the leaves over his head, he caught the rustle. The fact that there was nothing from the direction of the ponies showed they had ceased to crop the grass and were lying down. The safety of the camp was in his hands. If he forgot his duty, it might be fatal to all.
The sense of this responsibility and the newness of his position made Jack Dudley more wakeful than he could have been under any other circumstances. To these causes, also, was due a suspicious nervousness which made him see danger where it did not exist. The rustling of a falling leaf caused him to start and glance furtively to one side, and at a soft stir of the leaves under a breath of wind, or a slight movement of the sleeping ponies, he started and grasped his rifle with closer grip.
All this was natural; but there came a moment, not far from midnight, when there remained no doubt that some person or animal was moving stealthily through the grove, near where he was standing. It will be remembered that his position was such that the trunk of the large oak acted as an impenetrable screen between him and the camp-fire, which was burning so vigorously that its rays penetrated to a greater or less degree beyond him. Thus he could see anything moving within the circle of illumination, while he was as invisible to the keenest-eyed warrior as if the night was without a ray of light.
The first warning was through the sense of hearing. He had been deceived so many times that he suspected his fancy was playing with him again, but the faint tip, tip continued until such explanation was amiss.
"It is an Indian or a wild beast," was his belief.
The next minute he knew that, whatever it was, its position was between him and the outer edge of the grove. Since the ponies were on the opposite side of the fire, Jack was nearer the intruder than either they or his friends, sleeping by the camp-fire. Recalling that his place was the most favorable possible, he remained as motionless as the tree-trunk behind him, and to which he stood close enough to touch by moving his foot a few inches backward.
The situation being thus, it followed that if the man or beast continued its advance it must come into sight, while Jack himself was invisible. He therefore held his Winchester ready for instant use and waited.