From the ArcaMax Publishing, Trivia Newsletter:
http://www.arcamax.com/news/trivia/s-349231-146048
According to Vitruvius, a new crown in the shape of a laurel wreath had been made for King Hiero II, and Archimedes was asked to determine whether it was of solid gold, or whether silver had been added by a dishonest goldsmith. Archimedes had to solve the problem without damaging the crown, so he could not melt it down. While taking a bath, he noticed that the level of the water rose as he got in. He realized that this effect could be used to determine the volume of the crown. By dividing the weight of the crown by the volume of water displaced, its density could be obtained. The density of the crown would be lower if cheaper and less dense metals had been added. Archimedes then took to the streets naked, so excited by his discovery that he had forgotten to dress, crying "Eureka!" "I have found it!"
This news arrived on: 05/17/2008