three o’clock
He said he would n't keep you for more than a few minutes , if you could spare him a short interview . '' `` Any luck last night ? '' Ambrose sighed . `` I was up till three o'clock again . Once I thought I was on the track of it . I have come to the conclusion now that it 's one of those codes that depend upon shifting quantities . I shall start again to-night on a different idea .