midnight
Perceiving that the ball was perforated , she secured it in an instant to the end of the clue , which she held in her hand , and , judging that the object of her friends was to establish a communication from their side , cast it back to them with a great effort , having first passed the twine around the mullion , by aid of which Crispus had lowered down his messenger . The soldier caught the bullet , and nodded his approbation with a smile , but again receded into the bushes , suffering the slack of the twine to fall down in an easy curve into the ravine : so that the double communication would scarce have been perceived , even by one looking for it , in the gathering twilight . The boy 's voice once more reached her ears , though his form was concealed among the shrubbery . `` Fear nothing , you are safe , '' he said , `` But we can do no more until after midnight , when the moon shall give us light to rescue you . Be tranquil , and farewell . '' -- Be tranquil ! -- tranquil , when life or death -- honor or infamy -- bliss or despair , hung on that feeble twine , scarce thicker than the spider 's web !