<I’ll start this off in GQ as it is amenable to factual answer, but if it gets too discursive I can see IMHO in its future>
The (increasingly eccentric) Column 8 in the Sydney Morning Herald today has a fascinating story on an accidental meeting in 1847 between Lord Kelvin and James Prescott Joule during the latter’s honeymoon in the Alps (Joule suitably equipped wiith his new wife and a long thermometer).
This got me to wondering: which other individuals after whom scientific units have been named have met face to face? I exclude those whose work together won them the necessary fame to rate unitworthiness.
BTW the question the column was meandering its way to addressing was: is it possible to stir water enough to generate sufficient heat by internal friction to boil it?
Well, here’s a list of people with units named after them. I’m sure I forgot some. I’ll leave it to someone else to figure out which of them were alive and approximately the same time and place, and try to uncover stories like those in the OP. Anyway, I hope this helps get started on answering the question.
Bonus Question 1: How many of these scientists’ first names do you know without looking? I could only get two.
Bonus Question 2: You already know that the unit of capacitance, the farad, is named for Faraday. But what other unit is named for him?
Obligatory joke: All the great physicists of history are playing tag up in heaven, and Einstein (who is currently “it”) sees Newton and starts running for him. Newton looks back, sees Einsten coming, and quickly pulls a piece of chalk out of his pocket, and draws a large square on the ground, then steps directly into the center of the square. “Aha! I’ve got you!” cries Einstein, as he tags Newton. “No, you haven’t,” Newton answers, "You see, you’ve got Newton… over a square meter. So actually you got Pascal.
It’s perhaps worth noting that while Thomson (i.e. Kelvin) and Joule met under those circumstances and the quote in the column is accurate, there was a significant degree of anecdotal embroidery going on here. Thomson only added the vivid detail about the thermometer much, much later and in his contemporary account of the meeting he was quite clear that Joule was only speculating about measuring a temperature difference in a waterfall during this encounter. There’s no independent evidence that Joule actually carried out the experiment - or claimed to have done so - and thus it’s probable that Thomson improved the story over the years.
An obvious example is that Kelvin frequently met Faraday (the Farad). Faraday had also met Ampere, notably on 23/11/1813 in Paris. Though Ampere was there to meet Humphrey Davy and Faraday was only present as Davy’s assistent.
It’s clear from their letters that Faraday and Henry had met in person, I presume during the latter’s trip to London in 1837.
Kelvin also met Tesla, at a reception given by the American Institute of Electrical Engineers in New York in April 1902.
Both Kelvin and Siemens were at the International Conference for the Determination of Electrical Units in Paris in 1881 - which named the likes of the amp and volt - and they presumably met. It wouldn’t surprise me if Weber was also there.
On the other hand, neither Newton or Pascal would have met any of the others.
An obvious case I missed above is Joule and Faraday. For instance, they both attended the British Association meeting in Oxford in June 1847 and there’s a letter from Joule to Faraday several weeks later that refers back to a converstaion they’d had there. Kelvin was also at the meeting.
Kelvin was later a close colleague of Pierre Curie in the years before the marriage to Marie and the pair met in Paris in 1893. All three were at the International Congress of Physics in Paris 1900 and Marie and Thomson were surely introduced by Pierre on this occasion.
The Curies certainly would have known Becquerel, but I can’t offhand point to a specific meeting in person. (Though they shared the 1903 Physics Nobel, the Curies didn’t travel to Stockholm for the ceremony.) Again it wouldn’t surprise me if Becquerel and Kelvin met in Paris in 1900.
This is rapidly turning into the Six Degrees of Baron Kelvin.
The lumen is named for Louis Jean Lumière.
The phot for Photius I of Constantinople.
The bel for Alexander Graham Bell.
The Edison is equivalent to 100 Amps.
The poise comes from Jean Louis Marie Poiseuille.
The atomic mass unit amu is sometimes called the Dalton after the chemist John Dalton.