"A Double Glass O' The Inwariable"

Context: Mr. Pickwick, president of the Pickwick Club, and several companions have agreed to travel to various areas of England, such as Bath and Rochester, and to report of their adventures and travels to the other club members. In the meantime, Mr. Pickwick has an unsolicited adventure: when he rented his present quarters, Mrs. Bardell, his landlady, misunderstood him and concluded that he intended to marry her, and now is suing him for breach of promise. Old Mr. Weller, father of Sam Weller, servant of Mr. Pickwick, meets his son at the Blue Boar to pass along some advice for Mr. Pickwick as he faces trial. As he enters, Mr. Weller is disturbed to find Sam composing a Valentine, this being the thirteenth of February, but, reassured that Sam has no intentions of matrimony, he says in his cockney accent to the waitress:

. . . "A double glass o' the inwariable, my dear."
"Very well, Sir," replied the girl; who with great quickness appeared, vanished, returned, and disappeared.
"They seem to know your ways here," observed Sam.
"Yes," replied his father, "I've been here before in my time. . . ."