According to Ada, she told the driver to turn somewhere near Morzhey (a Russian pun on ‘Morges,’ a town on Lake Geneva mentioned by Karamzin in “The Letters of a Russian Traveler”):
He left the balcony and ran down a short spiral staircase to the fourth floor. In the pit of his stomach there sat the suspicion that it might not be room 410, as he conjectured, but 412 or even 414, What would happen if she had not understood, was not on the lookout? She had, she was.