eight o'clock
`` I suppose -- '' A long reverberating ring of the bell cut short her remark . The two friends exchanged questioning glances . `` It ca n't be one of the girls . It 's only eight o'clock , '' was Emma 's quick comment . Grace opened the door and listened intently . Emma joined her , peering over her shoulder . Then Miss Duncan 's dignified assistant in English gave an unmistakable , though subdued , war whoop , and , seizing Grace by the hand , made for the stairs .