"I'll try it."

Jacques skillfully wheeled the machine and describing a great loop, doubled on his course. Meanwhile he rose to greater and greater heights. The earth was now many thousand feet below; even the clouds were beneath them in many instances.

"He's running away," cried Earl suddenly.

"After him, Jacques! After him!" shouted Leon.

The German, perceiving Jacques' purpose had turned and was now fleeing at full speed. No more did he circle and maneuver for position; his course was straightened out and he raced for safety.

"We'll get him," shouted Leon. "We're gaining fast."

Closer and closer they came to their enemy. Little by little the distance between the two racing machines decreased. The three boys leaned forward tensely as if to urge their flier on; Leon and Earl sat ready to open fire with the machine-gun the moment Jacques should give the word.

Suddenly the German machine shot downward; it was a ruse to throw off the pursuer who followed so relentlessly, but it was of no avail. Jacques did the same thing and earthward the big monoplane rushed at breakneck speed.

The German flier turned and started back; Jacques followed. All the time the three boys were gaining on their foe. They were almost within range now and the twin brothers prepared to carry out their part of the task in hand.

"Get ready," warned Jacques when they were only a few hundred yards behind their opponent and some distance above him.