three o'clock
You have made a blunder , which must not be repeated . '' `` Yes , sir , '' said Sam , glad to get off with no sharper admonition . He returned to the post office , and this time he did his errand correctly . At three o'clock Sam was permitted to leave the office and look out for a boarding-place . He had managed to scrape acquaintance during the day with Henry Martin , an errand boy in the next store , and went to consult him . `` Where do you board ? '' he asked .