"But what's the good of that when the opening wedge couldn't be driven?" impatiently queried Roque.
Schneider scratched his head. He had no answer.
"There is one thing sure," exclaimed the secret agent, "and that is, I must be on the move, for this isn't the only fish scorching in the pan."
Billy just then edged into the conversation. He had made an alarming discovery. The petrol supply in the biplane tanks was at low mark. The aviators had expected to replenish long before this, and the disaster at Lupkow had spoiled their last chance.
"Oil nearly out, sir," were the words that brought Roque to his feet like a jumping-jack.
"The devil you say!"
Here was a quandary that completely upset the chief.
"We ought to have filled day before yesterday," explained Billy, "but you know why we didn't."
"The only thing to do that I see," advanced Henri, "is to add the supply of one machine to that of the other, and two of us hunt for the new camp of the Austrians."