"The flashlight powder—I wonder if we can get enough of that?" spoke Joe. "It'll take quite a lot."
"We must get it—somehow," declared the captain. "I fancy we have some on hand, and perhaps you can make more. There is quite a chemical laboratory here at the dam. But we've got to hustle. The attempt is to be made some time after midnight."
"Hustle it is!" cried Blake. "Come on, Joe."
CHAPTER XXIV
THE TICK-TICK
"Put one camera here, Joe."
"All right, Blake. And where will you have the other?"
"Take that with you. Easy now. Don't make a noise, and don't speak above a whisper!" cautioned Blake Stewart. "You'll work one machine, and I'll attend to the other. We'll put the automatic between us and trust to luck that one of the three gets something when the flash goes off."
The two boys, with Captain Wiltsey, had made their way to a position near the spillway, below the great Gatun Dam. It was an intensely dark night, though off to the west were distant flashes of lightning now and then, telling of an approaching storm. In the darkness the boys moved cautiously about, planting their cameras and flashlight batteries to give the best results.