seven o'clock
Of course , there was no more to be said . Walter did not care to interfere with the professor 's plans , and he was ashamed to admit that he was nervous and alarmed . Perhaps his fears were groundless . He began to think so when at seven o'clock the stable-boy brought round a powerful black horse to the front of the inn , and the stranger who had given him so much anxiety vaulted into the saddle and rode away , without even turning to look at him . `` Who is that fellow ? '' he asked of an old man who stood near , smoking a clay pipe . The old man looked thoughtfully at the stranger , who had now ridden out of the yard .