about two o’clock
`` Why did n't he come himself ? '' `` I am trying to explain , '' Lady Mary protested . `` This afternoon he had an important paper to turn into cipher and hand over to the Prime Minister at the Duchess of Montford 's dance to-night . The Prime Minister will arrive in a motor car from the country at about two o'clock , and the first thing he will ask for will be that paper . It has been stolen ! '' `` At what time did your brother finish copying it , and when did he discover its loss ? '' Ruff asked , with a slight air of weariness .