e_ on the sea a while ago, but then I thought it couldn't
be--thought I was getting delirious or something."

"Going back up?"

"I--I'll--In a moment or two I'll try."

A few moments later he did try, but it was no use. His nerve was gone.
His knees trembled so he could scarcely stand. His hands shook as with
the palsy. It is a terrible thing for a climber to lose his nerve while
in the air.

"No use," he told himself. "I'd only get shaken off again and next time
I'd be out of luck. Shame too, just when I was getting things."

Again he caught his companion's call.

"Storm's almost here! Guess we'll have to climb."

Even as he spoke, there came a flash of lightning which revealed a solid
black bank of clouds which seemed a wall of ebony. It was moving rapidly
toward them; was all but upon them.

"Better climb; climb quick," he breathed through the tube.

CHAPTER XIX

THE MAP'S SECRET

While all these things were happening to the boys on the seaplane,
Curlie Carson and Joe Marion were working hard to repair the damage done
to their radiophone set by the lightning. With the boat pitching about
as it was, and with the wind and waves keeping up a constant din, it was
a difficult task.

Just what coils and instruments had been burned out it was difficult to
tell. All these must be tested out by the aid of a storage battery. When
the defective parts had been discarded, it was necessary to piece
together, out of the remaining parts and the extra equipment, an
entirely new set.

"Have to use a two-stage amplifier," shouted Curlie, making himself
heard above the storm.

"Lower voltage on the grid, too," Joe shouted back.

"Guess it'll be fairly good, though," said Curlie, working feverishly.
"Only hope it didn't burn out the insulation on our aerials. Want to get
her going again quick. Want to bad. Lot may depend on that."

The insulation on the aerials was not burned out. After many minutes of
nerve-racking labor they had the equipment together again and were ready
to listen in.

Curlie flashed a short message in code, giving the name of their boat
and its present location, then, with the receiver tightly clamped over
his ears, he settled back in his chair.

For some time they sat there in silence, the two boys and Gladys
Ardmore.

The beat of the waves was increasing. The wind was still rising, but as
yet no rain was falling.

"Queer storm," shouted Joe. "Haven't gotten into it yet. Will thoug