John W. Grey, The Master Mystery
“ Again he looked about the cavern, then turned hurriedly, picked up the motor, passed out the steel door, clanged it shut, and locked it.No sooner had Brent shut the door, however, than it seemed as if the very face of the outer rocky wall of the cavern began to move—to tilt, as if on hinges.If a human eye had been in the Graveyard of Genius at that instant it would have sworn that it perceived in the inky blackness of the tilting rock a passage, and in the shadows of that passage a huge, weird, grotesque figure peering in. ”
