Joe was the first to respond, and the sound became louder. Then Herb and Jimmy followed suit, and it was evident that they served as amplifiers, for with each additional hand the music swelled to greater volume.
The boys looked at each other as if asking whether this was all real or if they had suddenly been transferred to some realm of fancy. They would not have been greatly surprised to wake up suddenly and find that they had been dreaming.
But there was no delusion about it and they listened without saying another word until, in a glorious strain of melody, the selection came to an end. Nor did they break the silence until a band orchestra was announced and crashed into a brilliant overture.
While it was still in full swing, Bob had an inspiration. He took off his headphones and clamped them on to the phonograph that stood on a table near by. Instantly the music became intensified and filled the room. When all their hands were on the wire, it became so loud that they had to close the doors of the phonograph.
“Well,” gasped Bob, when the last strain had died away and the demonstration was complete, “that’s something new on me.”
“Never dreamed of anything like it,” said Joe, sinking back in his chair. “Of course we know that the human body has electrical capacity and that operators sometimes have to use metal shields to protect the tube from the influence of the hand. And in our loop aerial at Ocean Point you noticed that the receptivity of the tube was modified when we touched it with our fingers.”
“Of course, in theory,” observed Bob thoughtfully, “the human body possesses inductance as well as capacity, and so might serve as an antenna. But I never thought of demonstrating it in practice.”
“So Bob is an aerial,” grinned Herb. “I always knew he was a ‘live wire,’ but I never figured him out as an antenna.”
“And don’t forget that if Bob is an aerial we’re amplifiers,” put in Jimmy.
“There’s glory enough for all,” laughed Joe. “We’ll have to tell Doctor Dale and Frank Brandon about this. We’ve got so many tips from them that it’s about time we made it the other way around.”