It wasn’t vaccines, although that’s what most people would say. It was the development and implementation of the water chlorination system by John Leal and George Warren Fuller in Jersey City, NJ, in 1908. As this system was adopted across the country, infectious disease fatalities dropped to close to zero over the next two decades. This was a true, real-world miracle of science, and if anyone deserves to be included in history books or celebrated as giants of science, it is Leal and Fuller. Their invention and tireless promotion of it saved millions of lives, and yet no one knows who they are. They’re lost to history, proving yet again that we are never even aware of the people whom we most benefit from.
