Understanding gravity is not only essential for understanding the motion of objects on Earth, but also the motion of all celestial objects, and even the expansion of the Universe itself. In this book George Gamow takes an enlightening look at three scientists whose work unlocked many of the mysteries behind the laws of physics: Galileo, the first to examine closely the process of free and restricted fall; Newton, originator of a universal force; and Einstein, who proposed that gravity is no more than the curvature of the four-dimensional space-time continuum. The author has illustrated the book himself with some technical fanciful drawings. Starting with a chapter on Galileo's pioneering work, this volume devotes six chapters to Newton's ideas and other subsequent developments and one chapter to Einstein, with a concluding chapter on post-Einsteinian speculations concerning the relationship between gravity and other physical phenomena, such as electromagnetic fields.