Hazard shook his head slowly, as if the question were too deep for
immediate answer and they had better defer judgment.

The flashes continued, and as the boys soon noted, at irregular
intervals of duration and disappearance. Now they were long, now short;
and again they came and went with great rapidity, or ceased altogether
for several moments at a time.

"I have it!" Hazard's face lighted up with the coming of understanding.
"I have it! That fellow up there is trying to talk to us. He's flashing
the sunlight down to us on a pocket-mirror--dot, dash; dot, dash; don't
you see?"

The light also began to break in Gus's face. "Ah, I know! It's what they
do in war-time--signaling. They call it heliographing, don't they? Same
thing as telegraphing, only it's done without wires. And they use the
same dots and dashes, too."

"Yes, the Morse alphabet. Wish I knew it."

"Same here. He surely must have something to say to us, or he wouldn't
be kicking up all that rumpus."

Still the flashes came and went persistently, till Gus exclaimed: "That
chap's in trouble, that's what's the matter with him! Most likely he's
hurt himself or something or other."

"Go on!" Hazard scouted.