physicsworld.com Comment: Robert P Crease Critical Point Missed metric moment The unfortunate saga of full of revolutionary sympathizers. Dombey was helpless to avoid becoming a Joseph Dombey contributed to political pawn. The presence of an emissary the failure of the US to capitalize of the revered Committee of Public Safety from the home country inflamed the fervour on an early opportunity to go of the locals against the governor, who had Dombey arrested and imprisoned. A mob metric, says Robert P Crease amassed to demand the release of the man who was an official representative of the On 17 January 1794 a French doctor and French government. botanist named Joseph Dombey stepped Dombey’s release incited the mob to take aboard the Soon, a brig departing from revenge against his captors. Standing on the for Philadelphia. Dombey bore a bank of a channel, Dombey tried to stop the

letter of introduction from the Committee National Institute of Standards and Technology Museum violence, but was pushed off the bank into of Public Safety, the executive body that the water. He was unconscious when fished ruled during the Reign of Terror. A weighty issue Joseph Dombey’s efforts to bring the out, and caught a raging fever. The governor Dombey was carrying to the US Congress a new kilogram to the US were ultimately doomed. took Dombey into custody, interrogated him copper length prototype – newly named the and put him back aboard the Soon. metre – and a copper kilogram, which were Right after it left the harbour, the ship was intended to help the US reform its system of The US had inherited attacked by British privateers who seized its weights and measures. cargo and took the crew hostage. Despite The French revolutionaries had chosen disguising himself as a Spanish sailor, Dom- their emissary well. Dombey had an enga- its measures from bey was recognized and imprisoned for ran- ging personality and a wealth of scientific som at the British colony of , learning that would surely impress the Britain, but their flaws where in April – still ailing – he died and was Americans. “He had integrity, courage and buried. Back in France, the Committee of a sense of adventure,” writes the historian were well known Public Safety was occupied with its own trou- Andro Linklater in his 2002 book Measuring bles, nobody was concerned by the absence America (Walker and Co.) “He was the ideal well known, and influential American states- of news from Dombey, and it learned of his choice in every way but one – his luck was men had been seeking to reform the US sys- fate only in October. phenomenally bad.” Had Dombey succee- tem for years. One was Thomas Jefferson, Dombey’s metre and kilogram are appar- ded, today we might not be in the ludicrous the first US secretary of state (1789–1793) ently lost, though the National Institute of situation of the US – the world’s largest and an admirer of French science and cul- Standards and Technology in Washington, economy – persisting with non-SI units. ture. In 1790 he asked Congress to adopt DC – which still seeks US conversion to SI – a decimal system of weights and measures has in its collection other prototype stan- Metrological opportunity similar to the one the French were about to dards that were made in France at about the As a young man, Dombey (1742–1794) was adopt. In 1791, in his first presidential address same time. an avid student of medicine and natural his- to Congress, George Washington noted that tory, and became a physician. In 1776, at the “a uniformity in the weights and measures of The critical point age of 34, he was assigned to a Spanish bo- the country is among the important measures In 1794 a strong political push might have tanical expedition to , during submitted to you by the Constitution”. settled things in the metric system’s favour. which he built up a collection of specimens of The following year, Congress appointed a “The sight of those two copper objects,” plants from that continent, in the process committee that recommended Jefferson’s Linklater writes, “so easily copied and sent earning himself a seat in the French Acad- proposals. It was a key moment for US out to every state in the Union, together with emy. His experiences on this excursion were metrological reform. Western nations were the weighty scientific arguments supporting challenging – he contracted dysentery, and being seized, settled and surveyed – and any them, might well have clarified the minds of was forced to delay publishing his findings delay in implementing a new system would senators and representatives alike. The vi- until after his Spanish colleagues. Disgusted make it harder to overturn the existing one. brant, determined personality of Dombey with the politics of , he retired to Lyon But while Congress considered the commit- could have created an immediate empathy. to practise medicine in a military hospital. tee’s recommendation, it had other pressing And today the US might not be the last coun- Not a good choice. During the revolution, business and put off taking a vote. This is try in the world to resist the metric system.” Lyon was an enclave of resistance to the Reign how matters stood when Dombey set sail in For a country to switch to a new measure- of Terror, and was attacked and punished January 1794. ment system is an immensely difficult under- by the revolutionaries. Dombey watched taking requiring strong leadership, political his patients dragged from the hospital and Never-ending journey will and the right social climate. All these guillotined. Worried about his sanity, well- Due to a series of misfortunes, Dombey were present in the US in 1794, but the mo- connected friends arranged another expedi- never made it to American shores. In March, ment was not exploited. It will be a long time tion for him – to the US, to collect botanical as the boat neared Philadelphia, a fierce before the US has a similar chance again. specimens and to bring samples of the new, storm damaged the brig and drove it south rational system of weights and measures to to the Antilles, where it had to land at Point- Robert P Crease is chairman of the Department France’s ally. à-Pitre in Guadeloupe. This French colony of Philosophy, Stony Brook University, and historian The US had inherited its weights and was as politically divided as France itself. Its at the Brookhaven National Laboratory, US, measures from Britain, but their flaws were governor was royalist, but Point-à-Pitre was e-mail [email protected]

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