about ten o'clock
There was only one way to get rid of her , and to this one way Hilda 's thoughts turned gloomily . Over this thought she brooded through all the following day . Evening came , and twilight deepened into darkness . At about ten o'clock Hilda left her room and quietly descended the great staircase , and went over toward the chamber occupied by Mrs. Hart . Arriving at the door she stood without for a little while and listened . There was no noise . She gave a turn to the knob and found that the door was open .