nine o'clock
`` That is strange , certainly , Pierre , '' Philip said , struck alike by the fact and by the earnestness with which Pierre expressed it . `` Are you quite sure of what you say ? '' `` I am quite sure , sir . I returned here at nine o'clock , and saw this mark on our door . I did not pay much heed to it , but went upstairs . Then , as I thought it over , I said to myself , ` Is this a freak of some passerby , or is it some sort of signal ? ' Then I thought I would see whether our house alone was marked , or whether there were crosses on other doors .