Pull the String!

How did you ask a Victorian cab-driver to stop the cab? You pulled the string that ran from inside the cab, through the roof, to ... the driver's arm.

    The journey seemed endless; street after street was entered and left behind; and still they went jolting on. At last Mr Squeers began to thrust his head out of the widow every half-minute, and to bawl a variety of directions to the coachman; and after passing, with some difficulty, through several mean streets which the appearance of the houses and the bad state of the road denoted to have been recently built, Mr Squeers suddenly tugged at the check string with all his might, and cried, 'Stop!'
    'What are you pulling a man's arm off for?' said the coachman looking angrily down.
    'That's the house,' replied Squeers.