Please read Alexey Sklyarenko's annotations on Pale Fire, Ada and other Nabokov works here.
Leaving Ardis after his first summer there, Van Veen (the narrator and main character in VN’s novel Ada, 1969) asks Bouteillan (the French butler at Ardis) not to quote Delille to him:
Van’s black trunk and black suitcase, and black king-size dumbbells, were heaved into the back of the family motorcar; Bouteillan put on a captain’s cap, too big for him, and grape-blue goggles; ‘remouvez votre bottom, I will drive,’ said Van — and the summer of 1884 was over.