As before the birdmen made a circuit. They undoubtedly intended coming back again to try once more to drop a missile on the elusive van, and accomplish the mission on which they had been sent out.
Frank hardly knew what system of tactics to employ this time. He had tried them all, and would have to repeat. The best part of it was that the man above could not read his mind, and therefore would not be able to gauge his scheme in time to reap any benefit from it.
Then again it was likely that occasionally one of the bombs might be badly aimed, and fall over in the adjoining field. Frank was far from ready to give up. He would keep everlastingly at it, as long as the van driver could get his machine to obey his will, and there was a solitary chance for them to escape the destructive effects of those numerous explosions.
"This time I'll call in your ear what I want you to do," was what Frank told the pilot at the wheel. "But no matter whether it's stop short, or rush ahead, do it as quick as a flash. Be ready now, for they're almost up to the throwing point."
As the birdmen were going the same way as the van it was necessary that they get almost overhead before undertaking to make a throw. The missile would then be given a forward movement calculated to cause it to reach a certain point aimed at.
Frank had practiced this same thing himself many a time, first from a moving railway train, and latterly from a swiftly driven aëroplane. Thus he was in a position to know something about it.
Billy continued to make the best use he could of his mock gun. He labored under the fond delusion that he was thus doing his part in keeping the fliers at a respectable distance, which amounted to something after all.
As for Pudge, he could only lie there on his face unable to look up--it was so terrible to see that man-made bird in the air above them, just for all the world like a hawk he had watched hovering over the water ere making a swift descent and plucking a fish out of the lake with its talons.
While he lay there on his stomach waiting in dread Pudge felt the car give several erratic movements. He could not at first decide whether it was stopping or making a sudden dash, but he did hear the crash announcing the next explosion.