“Yes, they do follow rains, so I am told,” went on the Spaniard.  “Well, I do not wish your Canal any bad luck, but if a slide does occur I hope it will come when you can get views of it.”

“In the daytime, and not at night,” suggested Joe.

For several days nothing of interest occurred.  Blake and Joe sent back to New York the films of the mad rush of waters through the lock, and also dispatched other views they had taken.  They had gone to Culebra Cut and there tied up, waiting for a slide that might come at any time, and yet which might never occur.  Naturally if the canal engineers could have had their way they would have preferred never to see another avalanche of earth descend.

Mr. Alcando had by this time proved that he could take moving pictures almost as well as could the boys.  Of course this filming of nature was not all there was to the business.  It was quite another matter to make views of theatrical scenes, or to film the scene of an indoor and outdoor drama.

“But I do not need any of that for my purpose,” explained Mr. Alcando.  “I just want to know how to get pictures that will help develope our railroad business.”

“You know that pretty well now,” said Blake.  “I suppose you will soon be leaving the Canal—­and us.”

“Not until I see you film the big slide,” he replied.  “I wish you all success.”

“To say nothing of the Canal,” put in Joe.

“To say nothing of the Canal,” repeated the Spaniard, and he looked at the boys in what Blake said afterward he thought was a strange manner.

“Then you haven’t altogether gotten over your suspicions of him?” asked Joe.

“No, and yet I don’t know why either of us should hold any against him,” went on Joe’s chum.  “Certainly he has been a good friend and companion to us, and he has learned quickly.”

“Oh, yes, he’s smart enough.  Well, we haven’t much more to do here.  A slide, if we can get one, and some pictures below Gatun Dam, and we can go back North.”

“Yes,” agreed Blake.

“Seen anything of Alcando’s alarm clock model lately?” asked Joe, after a pause.

“Not a thing, and I haven’t heard it tick.  Either he has given up working on it, or he’s so interested in the pictures that he has forgotten it.”

Several more days passed, gloomy, unpleasant days, for it rained nearly all the time.  Then one morning, sitting in the cabin of the tug anchored near Gold Hill, there came an alarm.

“A land slide!  A big slide in Culebra Cut!  Emergency orders!”

“That means us!” cried Blake, springing to his feet, and getting out a camera.  “It’s our chance, Joe.”

“Yes!  Too bad, but it had to be, I suppose,” agreed his chum, as he slipped into a mackintosh, for it was raining hard.

CHAPTER XIX

JOE’S PLIGHT

From outside the cabin of the tug came a confused series of sounds.  First there was the swish and pelt of the rain, varied as the wind blew the sheets of water across the deck.  But, above it all, was a deep, ominous note—­a grinding, crushing noise, as of giant rocks piling one on top of the other, smashing to powder between them the lighter stones.