What did Archimedes do that history bears his name? What did he accomplish, was he the first to discover something or what?

had many
inventions and is regarded as one of the greatest mathematicians of all time. In general, he is
historically known for a wide range of contributions. Here are two that bear his
name. 

The Archimedes screw or screwpump, which looks somewhat like a drill,
is a machine designed to take water from lower level water supplies into...