midnight
Still no response ! Nor was it to be wondered at . She had struck with the entire force of her heart 's vibration , communicating , by some subtile magnetism , her own terror to the summons . Clifford would turn his face to the pillow , and cover his head beneath the bedclothes , like a startled child at midnight . She knocked a third time , three regular strokes , gentle , but perfectly distinct , and with meaning in them ; for , modulate it with what cautious art we will , the hand can not help playing some tune of what we feel upon the senseless wood . Clifford returned no answer . `` Clifford !