Archimedes was a Greek mathematician, physicist, engineer, inventor, and astronomer born in 287 BC in Syracuse. He made discoveries related to buoyancy and density when the king of Syracuse asked him to determine if a jeweler had cheated him by making the king's crown out of another metal instead of pure gold. While bathing, Archimedes noticed that his body weight seemed to decrease in water, leading him to realize objects immersed in water displace a volume of water equal to their own volume. He then used this principle to determine that the jeweler had used another metal by measuring the crown's displacement. This became known as Archimedes' principle of buoyancy.