In the late-eighteenth century, European chemists Antoine Lavoisier, Joseph Priestley, and Carl Wilhelm Scheele all individually claimed that they had first discovered the element oxygen. While the debate escalated among British, German, and French scientists, British physicians proved the existence of oxygen by turning to the international slave trade. They showed how lack of oxygen among enslaved Africans crammed in the bottom of ships, which traveled from Africa to the Caribbean, led to high mortality rates. The international slave trade, in turn, made a scientific theory legible. Oxygen later emerged as a key element in the periodic table but how the international slave trade gave it scientific validity has been forgotten.

This paper grows out of Prof. Downs' book project, "The Laboring Dead: From Subjugation to Science in Global History."