"No, I couldn't be positive," was the answer. "You see we didn't have more than a hasty glimpse of them, and then only by the light of a candle. But from what you Twinkle Twins tell us, it's evident that the same four—two in uniform and two without—who were in the dugout were also sending up smoke signals."
"Well, it looks that way," admitted Gerald. "Of course, there's always a chance that things may take a different turn, but there's enough here for headquarters to get busy on."
"The main thing to do, in my opinion," declared Jimmy, "is to find out if the fellows we saw in uniform in the dugout and the two the Twinkle Twins saw sending up signals are the same, and then to learn if they're the Bixtons."
"That's the idea!" exclaimed Bob. "But it's easier said than done."
"We'll help all we can," said the Twinkleton Twins, as they started off again in their aeroplane, the tank having been filled with gasolene.
The secret service men at headquarters, including Captain Frank Dickerson, at once acted after the boys had given the additional information in their possession.
Jimmy and his chums had few opportunities to learn what was done by Captain Dickerson and his associates to get on the trail of the smoke signal traitors. All they heard was that an investigation was being made and that every effort was being bent toward learning whether or not the Bixtons were involved. It would not do to accuse these two wrongly, even though they were of a caliber not greatly desired in the army. They were entitled to be considered innocent until proved guilty, and the private quarrel they had with Jimmy and Roger, because of the instrumentality of the latter in sending Mike Bixton to prison, had nothing to do with the smoke signal issue.
As for that personal quarrel, the threats the Bixtons had made against Roger and Jimmy did not greatly worry the two. They felt that they could look out for themselves even against two such bullies and braggarts as were Aleck and Wilbur Bixton.
Indeed, there was a time when it seemed as if the paths of the two signal corps men would not again cross those of Roger and Jimmy. For the two latter, with their chums, were sent to a distant sector where the fighting was almost constant. And the chances were much against the four Brothers returning to the lines where the Bixtons were stationed.
There was hard fighting—so desperate, in fact, that Jimmy and his chums had little chance to think about anything except how to keep from being killed and how to inflict as heavy a punishment as possible on the enemy. The fighting was in a wooded country where advance was difficult, for the thick underbrush afforded shelter for many machine gun nests, and the Huns seemed to place more dependence on this style of fighting than on any other at this time and place.