ten o'clock
His supper was due at seven . At eight it would begin to get dusk . The moon was rising later each night , and it would not appear over the forests until after eleven . He would go through his window at ten o'clock . His mind worked swiftly and surely as to the method of his first night 's flight . There were always a number of boats down at Crossen 's place . He would start in one of these , and by the time Mercer discovered he was gone , he would be forty miles on his way to freedom .