"Yes; he's done for, and we can easily polish off the other one," remarked the lieutenant, as he watched the falling machine. "Now turn around quickly and dive for the one who is trailing us," said the lieutenant through the tube.

Ralph banked the machine, and brought it around as quickly as possible. The machine was not a quick-turning one, but the oncoming machine was not prepared for the manoeuver, for it seemed to hesitate which way to go. If it went to the left it would be impossible to use its gun, and if it turned to the right it would be at the mercy of the Frenchman's gun. The only remedy was to dive; down went the machine at a sharp angle. The lieutenant's shots went wild, but they were soon rid of their troublesome companion.

"I suppose we'll have the whole German flying corps after us now," said the lieutenant. "Turn for home."

No sooner had they turned than another machine came up, this time a most determined fellow.

"Up! up!" again came the command, "and keep pointing that way. You might also veer to the left."

This time it was one of the well-known Taubes, with the disadvantage, however, that she was a tractor,—that is, had the propeller in front, like the Bleriot monoplane, so that it prevented the driver from shooting head on, whereas the Farman biplane was a pusher,—that is, had the gun mounted in front, and the propeller behind the planes. During the evolution of circling, however, the biplane had to present a broadside, which gave the Taube a chance to pour in a stream of shot, many of which took effect.

"That was a close shot!" shouted Ralph through the tube. The lieutenant looked back, and pointed to the tube. A shot had gone through it, causing Alfred and Ralph to look at each other in undisguised dismay.

At every turn the lieutenant ground out the shot, and soon the barometer registered a height of 6,400 feet. Two miles more and the Taube made a peculiar turn, and glided to the right.

"You have hit him," said Alfred in excitement, and the lieutenant stopped churning.