eleven o'clock
`` Let 's go and see first , though , if Tom has n't a second lantern . We shall save time by it if he has . '' Our hurried search for a lantern was vain , however , so we determined to set off without one . As we closed the door behind us , our clock struck eleven , and a moment later we heard faintly the eleven o'clock whistle up at the Pelican . `` Good ! '' cried Joe . `` It is n't the boiler blown up , anyhow , so Tom 's safe ; for he is working underground and the explosion , whatever it was , was on the surface . ''