about eight o'clock
`` Heaven knows I would be only too glad to , mademoiselle , but I really do not see -- '' `` Put on your thinking-cap . I have never used any but the main stairway , but are there no servants ' stairways leading from my apartments ? '' `` Of course , mademoiselle . There are two such staircases , but you would run a great risk of meeting the servants if you used either of them ; that is , '' added the governess , thoughtfully , -- `` that is unless you should choose the time that they are at dinner , about eight o'clock , for example . '' `` Your idea is an admirable one . '' `` Mademoiselle should not rejoice too soon . '' `` Why ? ''