In 1794, Joseph Dombey found himself in a dangerous situation when his ship was surrounded by pirate ships in the Caribbean Sea. Dombey quickly disguised himself as one of the ship’s Spanish sailors in hopes of blending in. He was on his way to meet with Thomas Jefferson in Philadelphia to discuss the adoption of the metric system in the United States. However, his capture by pirates delayed this adoption by almost a century. While some historians view this as a missed opportunity, the United States eventually adopted metric standards in 1893. Dombey’s set of standards, including a meter and grave, ended up in the possession of land surveyor Andrew Ellicott. Today, it remains a mystery whether the grave on display at the NIST museum is the same one captured by pirates.
https://www.nist.gov/blogs/taking-measure/pirates-caribbean-metric-edition