The book "Discourse dedicated to the Grand Duke of Tuscany Cosimo II concerning the floating of bodies on water and their immersion in water" was published by the outstanding Italian physicist, astronomer and scientist Galileo Galilei. In this scientific work, he investigates phenomena related to the properties of water and the behavior of bodies in water. Galileo conducts research and experiments to better understand the physical laws that determine the movement of floating and submerged objects. This book is an important contribution to the development of hydrodynamics and fluid physics and became one of Galileo's important scientific works.