Three o'clock
`` Because -- because -- By Jove , I ca n't say , because I do n't know , '' cried Barbican with a quiet smile on his countenance . `` Oh what a lot of volumes , '' cried Ardan , `` could be made out of what we do n't know ! '' `` At present , for instance , '' observed M'Nicholl , `` I do n't know what o'clock it is . '' `` Three o'clock ! '' said Barbican , glancing at his chronometer . `` No ! '' cried Ardan in surprise .