"Sounded young. Some boy in late teens, I'd say. Though it might have been a girl. She might have changed her voice to disguise it. You can't tell. Had two cases like that in the last three weeks. You never can tell about voices."

"No," said Curlie, thoughtfully, "you never can tell. That's about the only thing you can be sure of in this strange old world. You can always be sure that you never can tell. Thing that looks like one thing always turns out to be something else.

"Point is," he continued after a moment's deep thought, "somebody's getting past our guard. Slamming us right in the nose and we're not doing a thing about it. Don't look like we could. I've got a theory but you can't go searching the estate of the richest man in your city just on theory; you've got to have facts to back you up, and mighty definite facts, too."

"Yes, that's right," agreed Coles. "But what do you make out of all that babble about airplane, map, ship and much gold? Do you suppose it's some smuggling scheme, some plan to get a lot of Russian or Austrian jewels into the country without paying duty or something like that?"

"I don't make anything out of that," said Curlie rather sharply, "and for the time, I don't jolly much care. The thing I'm interested in is the fact that we're being beaten; that the air about us is being torn to shreds every night by some careless or criminal person; that we're getting a black eye and a reprimand from the department; that sea traffic is being interrupted; that lives are being imperiled and we can't seem to do anything about it. That's what's turning my liver dark black!" He pounded the desk before him until instruments rattled and wires sang.

"But how you are going to catch a fellow when he goes tearing all over the map," said Curlie, more calmly, "is exactly what I don't know. You go down and get a bite of chow. No, go on home and go to bed. I'll take the rest of the shift. I want to think. I think best when I'm alone; when the wires sing me a song; when the air whispers to me out of the night; when the ghosts of dead radio-men, ghosts of operators who joked with death when the sea was reaching up mighty arms to drag them down, come back to talk to me. That's when I think best. These whispering ghosts tell me things. When I sit here all, asleep but my ears, things seem to come to me."

"Bah!" said Coles Masters, shivering, "you give me the creeps."

Drawing on his coat, he slipped out of the door, leaving Curlie slumped down in his chair already all asleep but his wonderful ears.

For a full hour he sat lumped up there. Seeming scarcely to breathe, stirring now and then as in sleep, he continued to listen and to dream.

Then suddenly he sat up with a start to exclaim out loud: