Wendy Moore’s riveting new book comes dressed as a how-to guide, which it is not. It is true that Thomas Day, the ‘ineligible bachelor’ of the subtitle, decided to follow what he understood Rousseau to be teaching in Emile and educate a woman to be his wife. For this purpose, in 1769, he plucked a likely looking child from the Foundling Hospital and set about training her. She was number 4579 and her name was Ann Kingston. This book tells her story.

The Foundling Hospital didn’t casually hand over its girls to unmarried gentlemen. Ann Kingston was officially apprenticed to Day’s friend, the married Richard Edgeworth, while another friend, lawyer John Bicknell, helped choose her. She left the orphanage legally under Edgeworth’s protection, but in the dubious care of Thomas Day; she