"Well, I'm not going to deny or affirm it," said Captain Dickerson, with a half smile. "But you boys seem to have luck in digging up mysterious matters, so if you hear of any bunch of fellows acting in a queer way or having certain chemicals in their possession you might let me know."
"We will, sir!" promised Bob, and Roger nodded his assent.
"I'll say this much," went on the captain. "The secret service department is working hard to locate the place where the signals came from, and trying to discover who sent them—if any were sent." The secret service official added this in order to be in conformity with his former statement of not admitting anything.
"We'll be on the watch as best we can," promised Roger.
Captain Dickerson walked on with other officers from the secret service department of the army, and Bob and Roger regarded each other with serious eyes.
"There's more to this than appears," declared Roger.
"I believe you," agreed his chum.
And in the days that followed they learned this more fully. For the location of a number of American batteries and machine gun nests was, in some manner, disclosed to the enemy. In consequence there was a shelling of these spots by the Germans, and considerable damage was done.
In one instance a battery had been carefully planted in a certain place and carefully camouflaged. It was hoped, after all the guns were in place, to open up a fusillade on a strong German position and carry it. This would have removed a menace from the American lines—a sort of small angle from which a raking fire was often sent.
But the night before the battery was to have opened it was almost completely destroyed by German shell fire. And the shells came with such accuracy, falling through the camouflaged screen, that it could not be doubted the exact location of the cannon was known to the Huns.