ed upon Rod that the fellow was actually making
some sort of signal to an unknown party further off. He used his eyes to
advantage, for he immediately caught what seemed to be an answering wave
from a patch of trees possibly three hundred yards away, and along the
side of the rise!

This complicated matters exceedingly. Oscar, then, was a fraud of the
first water. His story must be a tissue of lies from beginning to end.
Perhaps even his name had been assumed for a purpose, which was to
entrap the three American boys.

Rod had to think very fast just then. A plan of campaign must be
arranged on the spur of the moment, fitted to cover the case. Of course
he could not more than give a guess as to what it all meant, except that
there was danger in the air for himself and chums.

Could the pretended Swiss-American be in truth a German spy, bent on
taking them prisoner for some mysterious reason or other? Rod felt sure
this could not be, for he had failed to detect a sign of the Teutonic
guttural in the voice of the other. In fact, Rod was inclined to suspect
him of being of French origin, for when speaking he had all the shrugs
and grimaces which so often mark the natives of France, especially when
excited, and making explanations.

The three comrades were almost unarmed. Knowing the constant peril of
capture that menaced them, should they chance to run upon a squad of
German soldiers, Rod had decided that it would be the height of folly
for them to carry firearms; for if found to be armed they were likely to
be considered in the light of guerrillas, since they belonged to neither
army as enlisted men.

Of course the three of them would easily be able to overcome Oscar, who
did not appear to be very brawny in build. But if he had accomplices
near at hand even his capture might not prove sufficient to stave off
the danger.

Rod conceived a better scheme than to simply overpower the suspect. Why
not make him a hostage for the good behavior of his associates? The idea
seized hold of the boy, and in that instant he determined to put it into
immediate practice.

Oscar would be surprised to find that his cunning plot had been seen
through. In fact there would be others in the same fix, for Rod could
imagine the astonishment of Josh and Hanky Panky, possibly utterly
unsuspicious regarding the true course of events.

It happened that Rod had in his pocket a little tool shaped not unlike
one of those modern automatic pisto