Many of us know little more about Archimedes (287-212 B.C.) than his famous exclamation of "Eureka!" upon discovering that the spillage of water produced by an immersed object reveals the object's volume. That seemingly simple insight helped establish the key principles of buoyancy that govern the flotation of everything from boats to balloons.
Archimedes also had a profound impact on the development of mathematics and science, from the value of pi to the size of the universe. His reputation during his lifetime swelled to mythic proportions for his feats of engineering and his ingenious use of levers, pulleys, and ropes.