Winding up the clock

Tristram Shandy is an actual book, a bestseller of its time. You can check it out from your local library or read it online at Project Gutenberg.

It opens with the narrator talking about the circumstances of his conception. Parents are literally in the act, when mama says:

Pray my Dear, quoth my mother, have you not forgot to wind up the clock?--Good G..! cried my father, making an exclamation, but taking care to moderate his voice at the same time,--Did ever woman, since the creation of the world, interrupt a man with such a silly question?


"Winding up the clock" became a popular 18th century euphemism for sex. Bonus trivia: "Playing backgammon" referred to gay sex.