Henry watched Tom’s head disappear, he saw the little silvery bubbles rising, for an instant he could distinguish the darker shadow in the water which marked his friend, and then nothing but the rippling green surface of the river was visible through the open trapdoor in the floor of the dock. He and Frank were alone, Tom and Rawlins were beneath the river, and yet, down there at the bottom of the gurgling water, the unseen two could hear every word spoken in the room above. It was marvelous, fantastic and almost incredible. But even more wonderful and impossible events were about to take place. Frank had already heard Tom’s parting words over the set, although not a sound had issued from his helmet, and now, with the others under the water, Frank was again talking.
“Yes, I can hear you finely,” he said. “Say, it’s wonderful. Where are you? Right under
the dock? I’m going to let Henry talk to you. I feel as if I were dreaming!”
As Henry listened at the set and Tom’s words came to his ears he actually jumped, for he had never expected the words to come as plainly and distinctly as if Tom had been in the room with him and talking to him direct.
“That you, Henry?” came Tom’s voice. “Gee, but it’s great. I can hear you just as well as if I were up there. Does my voice sound loud?”
“Loud as if you were standing alongside of me,” Henry assured him. “I can’t believe you’re really under water.”
So, for some time, the three boys and Rawlins conversed, chatting and laughing, expressing their wonder and delight in boyish expletives and overjoyed at finding their plans and their work had proved such an immense success.
“We’re going off a ways,” announced Tom, at last. “Mr. Rawlins wants to find out how far away we can hear and send. We’re going to walk down the river. You keep talking and after we’ve gone a few hundred yards we’ll call you. If you don’t reply that you heard us we’ll keep walking
back and trying until you do get us. Then we’ll know our range.”
For a time, the two boys on the dock kept up a steady conversation with Tom and Rawlins, and, much to their surprise, the sounds of their friends’ voices continued as loud as when they were directly under the dock.