They strolled on, and this time Miss de Bourgh picked a forced peony and began to shred its petals. ‘Mrs Collins, you might have been fortunate enough to marry for affection, but matrimony for the rich is a matter of cold, hard business. Of contracts and lawyers’ agreements, of land and estates, pounds and shillings. The Colonel keeps making what is essentially a business proposal. A merging of assets, an exchange of goods. But the assets, and hence the power, are all on my side. He has only status, a certain position in society as his wife, to offer me. And such things carry no weight with me.’

Charlotte winced. Her marriage might not have been a matter of papers and seals in a dusty lawyer’s room, but it had been as brazen a trade as in any marketplace: her husband’s intact pride in exchange for her security. She had known this from the start, even if he could not acknowledge it. And yet their union had made them both content. She gained true pleasure from knowing that she was a good wife and helpmeet, and real affection flowed through their family. Their children were happy. Tom – oh, Tom! – she could swear he had enjoyed every minute of his short life; and for this and all her other blessings, she counted herself fortunate.

She wondered how to respond to these unexpected intimacies. Every question she wanted to ask was indelicate, but her companion seemed to have lost all reserve: ‘I see you wonder why I should not accept an offer that means I will stay in my home, but under the protection of a charming and universally liked man, educated and a brave officer, enjoying all the standing and congratulations due to a married woman. But I have never longed for union with any man; the truth is that I shudder at the idea. And my health will not stand the bearing of children. My line will end with my own flesh. There will be no issue from any marriage I might undertake.’

Charlotte stood still. The trickling of water through the pipes that warmed the hothouse seemed loud as she tried to compute what she had just heard.

Miss de Bourgh turned to her. ‘I see you are shocked. Well now, imagine the Colonel’s surprise when I was equally candid with him. He would indeed be safe, respectable and comfortable, married to me. But men assume that marriage means heirs, and the means of making heirs. I can offer no such thing.’