There was a moment’s pause, and twice Lieutenant Gebauer made a move as if to speak. But then he merely shrugged his shoulders and flipped the ashes from his cigarette.

“Life is too short to quarrel, Porter,” he remarked finally. “Have it your own way.”

“I intend to have it my own way.” Dave stepped a bit closer. “I believe you know well enough, Lieutenant Gebauer, that I have a little personal account to settle with you. But that can wait. Just the same, I want you and this cowardly young fellow here to understand that you have got to keep your distance. Otherwise there is going to be real trouble for both of you.”

“See here! You—you—can’t—er—threaten me like this!” stammered Gebauer, not knowing how to proceed.

“Come on, boys; I’ve had my say,” said Dave to his chums, utterly ignoring the splutterings of Gebauer. Nat was mumbling something under his breath, but what it was, nobody understood.

Then Dave and his friends left the bridge and the ruins around it and went on their way.

CHAPTER XVII
AT THE TRENCHES

The following week was such a busy one for Dave that Lieutenant Gebauer and Nat Poole were practically forgotten. The engineers were moved somewhat to the north of the position they had occupied, and were there set to work at their usual task of building roads and bridges.

“One thing is certain,” said Dave, one day when he and the others had knocked off for dinner. “Whatever ground our soldiers have taken they have managed to keep.”

“Oh, we don’t know how to retreat,” returned Phil, with a grin.