about nine o'clock
Half an hour later they were once more in front of the hotel , and interviewing a guide who had been recommended by the manager as an experienced canyon man . It ended in their making terms with John Henry , as the fellow gave his name ; though of course Frank was too wise to tell him what their real object was in exploring the tremendous gap . That could come later on . At about nine o'clock they started down the trail that led from Grand View into the depths of the fearful dip . And as they descended , following their guide , Bob found himself realizing the colossal size of everything connected with the rainbow-hued canyon walls . Nor was his mind made any easier when Frank took occasion , half an hour later , to bend toward him , and say in the most natural manner possible , though in low tones : `` They 're on the job again , Bob -- Abajo and Eugene -- because I happened to see them watching us start down the trail ; and they had some one along with them , perhaps a guide ; so we 'll have to take it for granted that they mean to dog us all the time , hoping to steal our thunder , if we make any lucky find ! '' Although Bob had anticipated such a thing , still the knowledge that it was actually coming to pass gave him a thrill .