That was enough to warn Frank of the terrible peril that overshadowed him at the moment.
Out came his revolvers, and his back went against the wall. Upward were flung his hands, and the weapons began to crack.
Two horses fell, sent down by the first two bullets from the pistols of the boy at bay.
But Frank found he could not shoot horses and save himself, for dark forms were pressing upon him, and he must fall into the clutches of the bandits in another moment unless he resorted to the most desperate measures.
"If you will have it, then you shall!" he muttered, through his set teeth, turning his aim on the human forms.
Spouts of red fire shot from the muzzles of the revolvers, and the cracking of the weapons was followed by cries and groans.
Through a smoky haze Frank saw some of the dark figures fling up their arms and topple to the ground within a few feet of him.
He wondered what had become of Hans and the professor, for he could see nothing of either, and they had been close at hand a moment before.
In the midst of all this, Frank wondered at his own calmness. His one thought was that not a bullet should be wasted, and then he feared he would find his weapons empty and useless before the desperadoes were rebuffed.
But this reception was something the bandits had not expected from a boy. They had no heart to stand up before a lad who could shoot with the skill of a Gringo cowboy, and did not seem at all excited when attacked by twenty men.