inventor knew that, at the other end of the line, was the
mysterious man who had spoken before.





CHAPTER XIX

THE BUZZING SOUND


"Are you Mrs. Damon?" came the question again--rather more
impatiently this time, Tom thought.

"Yes," answered the lady, glancing over at Tom. The extension
telephone was in the same room. Softly Tom switched on the
phonograph attachment. The little wax cylinder began to revolve
noiselessly, ready to record the faintest word that came over the
wire.

"You got a message from me yesterday," went on the hoarse voice.
In vain Tom tried to recall whether or not he had heard it before.
He could not place it.

"Who are you?" asked Mrs. Damon. She and Tom had previously agreed
on a line of talk. "Tell me your name, please."

"There's no need for any names to be used," went on the unknown at
the other end of the wire. "You heard what I said yesterday. Are