"With a flashlight?" asked Blake, wondering whether the captain depended on scaring those who would dare to plant a charge of dynamite near the great dam.
"With a flashlight, or, rather, with a series of them, and your moving picture cameras," the captain went on. "We want you boys to get photographic views of those who will try to destroy the dam, so that we will have indisputable evidence against them. Will you do it?"
"Of course we will!" cried Blake. "Only how can it be done? We don't know where the attempt will be made, nor when, and flashlight powder doesn't burn very long, you know."
"Yes, I know all that," the captain answered. "And we have made a plan. We have a pretty good idea where the attempt will be made—near the spillway, and as to the time, we can only guess at that.
"But it will be some time to-night, almost certainly, and we will have a sufficient guard to prevent it. Some one of this guard can give you boys warning, and you can do the rest—with your cameras."
"Yes, I suppose so," agreed Blake.
"It will be something like taking the pictures of the wild animals in the jungle," Joe said. "We did some of them by flashlight, you remember, Blake."
"Yes, so we did. And I brought the apparatus with us, though we haven't used it this trip. Now let's get down to business. But we'll need help in this, Joe. I wonder where Alcando—?"
"You don't need him," declared the captain.
"Why not?" asked Joe. "He knows enough about the cameras now, and—"