Rawlins grinned, “We’re under way now,” he remarked. “Have been for the past fifteen minutes. Didn’t you hear the engines?”
“Jove, you don’t say so!” exclaimed Mr. Henderson.
“Gosh, I can’t believe it!” cried Tom.
“Why, I thought that noise was just the dynamos!” put in Frank. “Say, are we under water?”
“Surest thing you know!” replied Rawlins. “She’s under her electric motors now and runs smooth as a watch. Come on, boys, and have a squint through the periscope.”
“We’ll stay behind a bit and talk to Smernoff,” said Mr. Pauling. “No use in keeping him locked up if he’s in earnest.”
Reaching the observation room Rawlins led the boys to the eye-piece of the periscope and as Tom squinted into it he gave a delighted cry.
“Gosh, Frank, we are under water! Say, I can see the island back there pretty near two miles away. Isn’t it great! Think of being in a real submarine under the sea!”
Frank was as delighted and interested as Tom when his turn came to have a look. Then, a few minutes later, the louder rumble of the Diesel motors throbbed through the undersea craft and Rawlins announced that they were on the surface.
“No use running submerged except when in sight of land or a vessel,” he said, “she doesn’t make half her speed underwater and it’s a strain on her and we might bump into a reef. I’m not any too familiar with the channels that will accommodate her submerged.”