"They've got a sentry posted here," he whispered, "I'd hoped they'd be too careless or too drunk to do it. Look over there a little to the right."
They peered through the bushes and saw, sitting on a tree stump, a Mexican, carrying a carbine, slung in the hollow of his arm. His back was toward them at the moment, but even while they gazed, he lazily rose and turned around, so that they caught a full view of his face. It was a rascally face that left no doubt in their minds that he was one of the bandit crew. A long knife was thrust in his belt, and he looked like an ugly customer to tackle in a fight. His small, piglike eyes looked listlessly about, and then, seeing no sign of danger, he reseated himself, and taking a flask from his pocket, applied it to his lips.
At a glance from Melton, they retreated as noiselessly as they had advanced, and not until they had gotten beyond earshot, did they stop for consultation as to their next move.
Bert and Tom felt their hearts beating high with excitement, but Melton was as cool and impassive as though he were seated on the veranda of his ranch.
While they waited for him to speak, he drew from its sheath a long double-edged bowie knife and fingered it thoughtfully.
"It's a long time since I've done it," he mused. "I wonder if I can do it now. I'll try it out first."
Rising, he went over to a tree about fifty feet away. At a height of six feet from the ground, he cut out a circle of bark, about the size of a saucer. The white patch stood out in strong contrast to the rest of the tree. Returning to the boys, who had looked on puzzled at his action, he planted himself solidly and took the bowie by the blade. A moment he stood thus, measuring the distance. Then he raised the weapon and hurled it at the bark. It whizzed through the air in a gleam of light, and struck two inches inside the circle, where it hung quivering. It was a marvelous bit of knife play, and Bert and Tom could hardly repress an exclamation.
"That's all I wanted to know," muttered Melton, as he came back, after pulling the knife from the tree and restoring it to its sheath. "It's a little trick that has saved my life once or twice before on the plains, and I wanted to make sure that I hadn't forgotten. I guess if I could hit that circle, I could do for the Mexican.
"For as you boys may imagine," he went on, "I wasn't doing this thing for pastime. We've got to get that sentinel out of the way. Of course, it would be an easy thing to wing him with a bullet. But that makes a noise and probably the camp is not far off. Our only chance lies in taking them by surprise. If they once get wind of our coming we'll have as much chance as a celluloid dog chasing an asbestos cat through Hades. I'd rather take this fellow alive if we could, for we might be able to get some valuable information from him. But I'm afraid he'd let out a yell or shoot off his gun before we could get to him. I guess we'll have to depend on this little persuader," he concluded, as he put his hand on the shaft of the knife.
Bert had been thinking rapidly.