Galileo Galilei is known for many scientific discoveries. Among them are the laws of the pendulum and falling bodies, astronomical discoveries, the hydrostatic balance, and the first air thermometer.But today we think of Galileo as the first of the modern scientists, for it was he who broke the centuries'-long stranglehold of ancient Greek learning. Often risking his own standing, Galileo boldly pointed out the errors of these ancient authorities and spoke out for something entirely new - experimental science.Galileo played an outstanding part in the development of modern science because at the core of his thinking was his insistence on measuring, weighing, and timing things. He first found the facts and from the facts deduced principles.Here is the simply-told life portrait of a courageous man and a truly original thinker.