“I only wish I could have had a hand in rescuing you,” the Spaniard went on.  “It would have been a manner of paying, in a slight degree, the debt I owe you boys.  But fate took that out of my hands, and you were saved by the same sort of slide that covered you up.”

“Yes, I guess I was born lucky,” laughed Joe.

Preparations for taking several views of the big Gatun Dam from the lower, or spillway side, were made.  One afternoon Mr. Alcando asked if he would be needed in making any views, and when Blake told him he would not, the Spaniard went off by himself, taking a small camera with him.

“I’m going to try my luck on my own hook,” he said.

“That’s right,” encouraged Blake.  “Go it on your own responsibility.  Good luck!”

“He’s trying hard, at all events,” said Joe, when their acquaintance had left them.

“Yes,” agreed Joe.  “He wants to make good.”

Several times after this Mr. Alcando went off, by himself for more or less prolonged absences.  Each time he took a camera with him.

It was a small machine, made more for amateurs than for professionals, but it gave good practice.

“How are you coming on?” asked Blake one day, when Mr. Alcando returned after a trip which, he said, had taken him to Gatun Dam.

“Oh, pretty well, I think,” was the answer, as the Spaniard set down his camera and carrying case.  “I got some good scenes, I believe.  When are you going to make the last of the spillway views?”

Blake did not answer.  He was listening to a curious sound.  It was a ticking, like that of an alarm clock, and it came from the interior of the carrying case that held extra reels of film for the little camera Mr. Alcando had.

Blake felt himself staring at the black box.

CHAPTER XXII

A WARNING

“What is the matter?” asked Mr. Alcando, as he noted Blake’s intent look.  “Is something—?” He did not finish.

“That sound—­in the film-case—­” began Blake.

“Oh, my alarm clock—­yes!” exclaimed the Spaniard.  “I take it out with me on my trips.  Often, when I have finished taking pictures, I try to do a little work on it.  There is one feature I can’t seem to perfect, and I hope some day to stumble on it.  Without it the clock is a failure.  I had it with me to-day, but I could make no progress—­none at all.  I think I shall put it away again,” and taking with him the case, from which came that curious ticking noise, he went to his stateroom.

Blake shook his head.  He did not know what to think.

“He’ll never make a good moving picture operator,” he said to himself.  “You’ve got to give your whole mind to it, and not be monkeying with inventions when you set out to get views.  An alarm clock!

“Suppose he does perfect it?  There are enough on the market now, and I don’t believe there’s a fortune in any of ’em.  He might much better stick to what he set out to learn.  Well, it isn’t any of my business, I suppose.  Joe and I have done all we can.”