before we cut off all communication."

Rapidly he sent out the call. Again and again his nervous finger
agitated the key--but there was no response.

"They--they don't answer," gasped Frank at last--heavy anxiety in
his tones.

"Oh, Frank, do you think anything serious is the matter?" cried
Harry.

"It may only be that the apparatus is out of order," replied the
elder brother seriously; "but it looks bad. That field wireless was
in prime condition and it would be next to impossible for them to
fail to receive our call."

"Well, there is only one thing to be done," remarked the practical
Ben Stubbs.

"And that is--?" queried Harry.

"To get back there as soon as possible, for if they need us they
need us dern bad," was the energetic reply.

Half an hour later the Golden Eagle, stripped of all her heavy gear
and only carrying just enough gasoline to get her to the river camp,
where the adventurers expected to find a reserve supply, rose slowly
into the air with her queer tow tugging behind on the wireless
ground rope. The boys had cached the wireless apparatus and the
other gear, to be called for at some more opportune time. To their