The American Eclipse of 1878 and the Scientists Who Raced West to See It
On a scorching July afternoon in 1878, the moon’s shadow descended on the American West, darkening skies from Montana Territory to Texas. This rare celestial event—a total solar eclipse—offered a priceless opportunity to solve some of the solar system’s most enduring riddles, and enterprising scientists raced to the Rocky Mountains to experience totality. Some, like University of Michigan astronomer James Craig Watson, hunted for a planet (called Vulcan) that was thought to exist between Mercury and the sun; others, like astronomical artist E.L. Trouvelot, sketched the sun’s mysterious corona. Vassar astronomer Maria Mitchell headed west with an all-female team of assistants and a societal goal to achieve—opening the doors of science to women. Even a young Thomas Edison got involved. During the eclipse, he aimed to demonstrate the value of his latest device—an infrared detector called the tasimeter—and to prove himself not just an inventor, but a scientist.
In this excerpt from American Eclipse: A Nation’s Epic Race to Catch the Shadow of the Moon and Win the Glory of the World, science journalist David Baron writes about the morning and afternoon just before the eclipse, when national anticipation was at its peak.