Lord Kelvin made fundamental contributions to thermodynamics, electromagnetism, and the mathematics of physics, formulating the second law of thermodynamics and developing the absolute temperature scale that bears his name. He also directed the laying of the first successful transatlantic telegraph cable in 1866.

Charles Messier was a comet hunter who compiled the Messier Catalogue of 110 nebulae and star clusters to prevent other astronomers from mistaking them for comets. Though he discovered only one comet himself, his catalogue remains one of the most enduring references in amateur astronomy.

Lord Carnarvon financed Howard Carter's excavations in the Valley of the Kings, leading to the discovery of Tutankhamun's intact tomb in 1922 — the greatest archaeological find of the twentieth century. He died in Cairo just months after the tomb was opened, fueling legends of the "Pharaoh's Curse."

Abner Doubleday was a Union general who fought at Fort Sumter and Gettysburg, but he is popularly — and controversially — credited with inventing baseball. A 1907 commission named him the game's inventor, a claim historians have long disputed.

Peter Claver spent forty years in Cartagena, Colombia, ministering to enslaved Africans arriving on slave ships, personally baptizing an estimated 300,000 people. He was canonized in 1888 and declared patron saint of Colombia and of the African missions.