“And so it was Alcando, all along,” observed Blake, a few days later, following an unsuccessful search for the Spaniard.

“Yes, our suspicions of him were justified,” remarked Blake.  “It’s a lucky thing for us that we did save his life, mean as he was.  It wouldn’t have been any joke to be suspected of trying to blow up the dam.”

“No, indeed,” agreed Blake.  “And suspicion might easily have fallen on us.  It was a clever trick.  Once we had the Government permission to go all over with our cameras, and Alcando, as a pupil, could go with us, he could have done almost anything he wanted.  But the plot failed.”

“Lucky it did,” remarked Joe.  “I guess they’ll get after that railroad man next.”

But the stockholder who was instrumental in forming the plot, like Alcando, disappeared.  That they did not suffer for their parts in the affair, as they should have, was rumored later, when both of them were seen in a European capital, well supplied with money.  How they got it no one knew.

The Brazilian Railroad, however, repudiated the attempt to damage the Canal, even apparently, laying all the blame on the two men who had disappeared.  But from then on more stringent regulations were adopted about admitting strangers to vital parts of the Canal.

“But we’re through,” commented Blake one day, when he and Joe had filmed the last views of the big waterway.  “That Alcando was a ‘slick’ one, though.”

“Indeed he was,” agreed Joe.  “The idea of calling that a new alarm clock!” and he looked at the brass-bound box.  Inside was a most complicated electrical timing apparatus, for setting off charges of explosive.  It could be adjusted to cause the detonation at any set minute, giving the plotter time to be a long way from the scene.

And, only because of a slight defect, Alcando would have been far from the scene when the little explosion occurred at Gatun Dam.

Once more the great Canal was open to traffic.  The last of the slide in Culebra Cut had been taken out, and boats could pass freely.

“Let’s make a trip through now, just for fun,” suggested Blake to Joe one day, when they had packed up their cameras.

Permission was readily granted them to make a pleasure trip through to Panama, and it was greatly enjoyed by both of them.

“Just think!” exclaimed Blake, as they sat under an awning on the deck of their boat, and looked at the blue water, “not a thing to do.”

“Until the next time,” suggested Joe.

“That’s right—­we never do seem to be idle long,” agreed Blake.  “I wonder what the ‘next time’ will be?”

And what it was, and what adventures followed you may learn by reading the next volume of this series, to be called “The Moving Picture Boys Under the Sea; Or, The Treasure on the Lost Ship.”

“Here you go, Blake!” cried Joe, a few days later.  “Letter for you!”

“Thanks.  Get any yourself?”