left to recover from the shock and slight injuries at
Gatun, while Blake and Mr. Alcando were at Culebra. For the shock
to the young moving picture operator had been greater than at
first supposed, though his bodily injuries were comparatively
slight.

"Well, what's next on the programme?" asked Joe of Blake, about
two weeks after the accident, when Blake had returned from
Culebra. Most of the work there was done, and the Canal was again
open, save to vessels of extreme draught.

"I guess we'll go on making pictures of Gatun Dam now; that is, if
you're well enough," spoke Blake. "How do you feel?"

"Pretty fair. How did Alcando make out?"

"All right. He's learning fast. We can trust him with a camera
now, out alone."

"That's good. I say, Blake," and Joe's voice took on a
confidential tone, "you haven't noticed anything strange about
him, have you?"

"Strange? What do you mean?"

"I mean while he was off there with you. Anything more about that
alarm clock of his? And did anything more develop about his
knowing the captain of that vessel that sunk the _Nama_?"

"No, that was only coincidence, I think. Why, I can't say that
I've noticed anything suspicious about him, Joe, if that's what
you mean," and Blake's voice had a questioning tone.

"That's what I do mean," spoke Joe. "And if you haven't I have."

"Have what?"

"I've been watching Alcando since you and he came back, and I
think he's decidedly queer."

"Suspicious, you mean?"

"I mean he acts as though something were going to happen."

"Another landslide?" asked Blake with a laugh. "No chance of that
here at Gatun Dam."

"No, but something else could happen, I think."

"You mean the--dam itself?" asked Blake, suddenly serious.

"Well, I don't exactly know what I do mean," Joe said, and his
voice was troubled. "I'll tell you what I noticed and heard, and
you can make your own guess."

"Go on," invited Blake. "I'm all ears, as the donkey said."

"It's no laughing matter," retorted his chum. "Haven't you
noticed since you and Alcando came back," he went on, "that he
seems different, in a way. He goes about by himself, and, several
times I've caught him looking at the dam as though he'd never seen
it before. He is wonderfully impressed by it."

"Well, anybody would be," spoke Blake. "It's a wonderful piece of
engineering. But go on."

"Not only that," resumed Joe, "but I've heard him talking to
himself a lot."

"Well, that's either a b