“I really do think of marrying”

As I wrote yesterday, Benjamin Thompson left a wife and infant daughter behind in New Hampshire when he joined the British side of the Revolutionary War.

Someday I’ll discuss how Thompson got reacquainted with his daughter Sally (shown here) in the 1790s, after he had become a count of the Holy Roman Empire and her mother had died.

For our current storyline, what matters is that when Count Rumford met Marie Anne Lavoisier in 1801, he was exchanging letters with his daughter. That correspondence is one of our main sources about the budding relationship between the two scientists.

At the same time, Rumford didn’t tell Sally as much as she wanted to know, so she pumped his friends for more information. By 1803 she was wondering if her father planned to remarry, a question that affected both her present family and her future prospects.

Sir Charles Blagden wrote back to Sally on 8 Aug 1803 to say:

I am still as much at a loss as I was in June to answer your question whether your father be going to marry. He is now, as I told you in that letter, making the tour of Switzerland with a very amiable French lady. But I have no reason to think that they have any idea of matrimonial connexion. When the Count comes to England, she is to return to Paris; at least so he writes me word.

But on 10 December Blagden reported:

All I can tell you about your father is this: He continued travelling with the French lady till about the middle of September, when she left him at Mannheim and returned to Paris. . . . I know that he was in that city on the 1st of November. . . . He continues very intimate with the lady, but whether it will end in a marriage I cannot say. My own opinion is rather inclined to the negative, yet I have no good foundation for it.

Since this was written I have received a letter from your father, dated at Paris, November 11. By this it is evident that he expects to marry the French lady, though nothing is yet finally determined.

Count Rumford himself finally broke the news that Sally already knew in a letter dated 22 Jan 1804:

I shall withhold this information from you no longer. I really do think of marrying, though I am not yet absolutely determined on matrimony. I made the acquaintance of this very amiable woman in Paris, who, I believe, would have no objection to having me for a husband, and who in all respects would be a proper match for me.

She is a widow, without children, never having had any, is about my own age, enjoys good health, is very pleasant in society, has a handsome fortune at her own disposal, enjoys a most respectable reputation, keeps a good house, which is frequented by all the first Philosophers and men of eminence in the science and literature of the age, or rather of Paris. And what is more than all the rest, is goodness itself. . . .

She is very clever (according to the English signification of the word); in short, she is another Lady Palmerston. She has been very handsome in her day and, even now, at forty-six or forty-eight, is not bad-looking; of a middling size, but rather en bon point than thin. She has a great deal of vivacity and writes incomparably well.

In another letter Rumford added: “She is fond of travelling, and wishes to make the tour of Italy with me. She appears to be most sincerely attached to me, and I esteem and love her very much.”

“Lady Palmerston” was Mary Mee Temple, wife of the second Viscount Palmerston. According to Rumford’s modern biographer Sanborn C. Brown, she and the count had an affair in the 1790s.

Obviously Rumford still admired Lady Palmerston enough to hold her up to his daughter as an exemplar of a clever woman. He remained in touch with the viscountess during his courtship, writing that he expected to marry by May 1804. In none of these letters, however, do I see Mme. Lavoisier’s name. One had to know.

COMING UP: The paperwork.