“Bully for you!”
“Walk farther off and see if we can get you,” suggested Tom over the phone.
“All right,” responded Rawlins.
Five minutes passed and then, rather faint, but still easily understandable, Rawlins’ voice again came to them.
“All right,” cried Tom. “How far away are you?”
“About five hundred yards,” replied the diver. “I can just hear you.”
“Well that’s about the limit, I guess,” remarked Tom, as Rawlins told him he was returning to the submarine. “Say, isn’t it just immense?”
“Wonderful!” agreed his father. “But let me ask a question. Suppose we overhear some one talking. How will you know where they are or whether they are under water or on land. It seems to me that’s a very important matter.”
“Golly, that’s so!” exclaimed Tom. “I hadn’t thought of that. Our loop aerials won’t work in here, I suppose.”
“Might,” commented Frank, and then, “What about that resonance coil? That might do.”