The proposal, conceived by a bunch of pointy-headed Parisian philosophes, sounded brilliant: A universal system of measurement, derived from decimal-based units and identified by a shared set of prefixes. It would end the era of merchants buying goods according to one unit, selling in another, and pocketing the ill-gotten profit. It would simplify scientific calculations and enable the free exchange of ideas around the world. It was an enlightened system for an enlightened time. If only the French scientists could persuade other countries to adopt it.

But pirates have a way of ruining even the best-laid plans.

In 1793, botanist and aristocrat Joseph Dombey set sail from Paris with two standards for the new "metric system": a rod that measured exactly a meter, and a copper cylinder called a "grave" that weighed precisely one kilogram. He was journeying all the way across the Atlantic to meet Secretary of State Thomas Jefferson - a fellow fan of base-ten systems who, Dombey hoped, would help persuade Congress to go metric.

Then a storm rolled in, knocking Dombey's ship off course. The unlucky academic was washed into the Caribbean - and straight into the clutches of British pirates. Technically, they were "privateers" because they were tacitly sanctioned by His Majesty's government so long as they only raided foreign ships. But it amounted to the same thing. The brigands took Dombey hostage and looted his equipment. The luckless scientist died in prison shortly after his capture; his belongings were auctioned off to the highest bidders.