Many people have heard two things about Archimedes: he was the greatest mathematician of antiquity, and he ran naked from his bath crying ``Eureka!''. However, few people are familiar with the actual accomplishments upon which his enduring reputation rests, and it is the aim of this book to shed light upon this matter. Archimedes' ability to achieve so much with the few mathematical tools at his disposal was astonishing. He made fundamental advances in the fields of geometry, mechanics, and hydrostatics. No great mathematical expertise is required of the reader, and the book is well illustrated with over 100 diagrams. It will prove fascinating to students and professional mathematicians alike.