born in Syracuse, Sicily, Archimedes is regarded as one of the greatest mathematicians and scientists of antiquity and one of the three greatest mathematicians of all time along with Isaac Newton and Carl Friedrich Gauss. He made founding contributions to the fields of hydrostatics, static mechanics, and pycnometry (the measurement of the volume or density of an object). He determined hydrostatic principles governing floating bodies, which are still applied to swimming today. He also is called the "father of integral calculus." Archimedes was an outstanding engineer; he formulated the Archimedes' principle of buoyancy and the law of the lever. It is supposed that Archimedes was the inventor of the screw, a device that can be used to raise water from a lower level to a higher level by turning a handle. Moreover, he is accredited with designing many war machines used in the defense of Syracuse, including the construction of lenses to focus the sun's light on Roman ships and huge cranes to turn them upside down.