gh in the popular mind Galileo is remembered chiefly as an astronomer, however, the science of mechanics and dynamics pretty much owe their existence to his findings. Before he was twenty, observation of the oscillations of a swinging lamp in the cathedral of Pisa led him to the discovery of the isochronism of the pendulum, which theory he utilized fifty years later in the construction of an astronomical clock. In 1588, an essay on the center of gravity in solids obtained for him the title of the Archimedes of his time, and secured him a teaching spot in the University of Pisa. During the years immediately following, taking advantage of the celebrated leaning tower, he laid the foundation experimentally of the theory of falling bodies and demonstrated the falsity of the peripatetic maxim, which is that an objects rate of descent is proportional to its weight. When he challenged this it made all of the followers of Aristotle extremely angry, they would not except the fact that their leader could have been wrong. Galileo, in result of this and other troubles, found it prudent to quit Pisa and move to Florence, the original home of his family. In Florence he was nominated by the Venetian Senate in 1592 to the chair of mathematics in the University of Padua, which he occupied for eighteen years, with ever-increasing fame. After that he was appointed philosopher and mathematician to the Grand Duke of Tuscany. During the whole of this period, and to the close of his life, his investigation of Nature, in all her fields, was never stopped. Following up his experiments at Pisa with others upon inclined planes, Galileo established the laws of falling bodies as they are still formulated. He likewise demonstrated the laws of projectiles, and largely anticipated the laws of motion as finally established by Newton. In statics, he gave the first direct and satisfactory demonstration of the laws of equilibrium and the principle of virtual velocities. I...
