A linha "whisper line" está em The Stars, My Destination do Alfred Best. Gully Foyle tem uma educação Monte Cristo na prisão por meio de conversas sussurradas com sua professora, Jizbella McQueen:
"...My God, this must be real! You're talking the gutter lingo. You must be real. Who are you?"
"Gully Foyle."
"But you're not in my cell. You're not even near. Men are in the north quadrant of Gouffre Martel. Women are in the south. I'm South-900. Where are you?
"North-111."
"You're a quarter of a mile away. How can we - Of course! It's the Whisper Line. I always thought that was a legend, but it's true. It's working now... It's a miracle."
"What's a miracle?"
"There's an acoustical freak in Gouffre Martel... they happen in underground caves... a freak of echoes, passages and whispering galleries. Old-timers call it the Whisper Line..."