To the Romans, science owes little beyond what is implied in their vast architectural monuments, buildings and aqueducts which were erected at home and in the countries of their conquests. The elder Pliny (23–79 A. D.) most nearly deserved to be called a man of science, but his work on natural history, comprised in thirty-seven volumes, is hardly more than a compilation of fable, fact, and fancy, and is sometimes termed a collection of anecdotes. He lost his life in the “grandest geological event of antiquity,” the eruption of Vesuvius, which is vividly described by his nephew, the younger Pliny, in “one of the most remarkable literary productions in the domain of geology” (Zittel). With the fall of Rome and the decline of Roman civilization came a period of intellectual darkness, from which the world did not emerge until the revival of learning in the fifteenth and sixteenth centuries. Then the extension of geographical knowledge went hand in hand with the development of art, literature, and the birth of a new science. Copernicus (1473–1543) gave the world at last a sun-controlled solar system; Kepler (1571–1630) formulated the laws governing the motion of the planets; Galileo (1564–1642) with his telescope opened up new vistas of astronomical knowledge and laid the foundations of mechanics; while Leonardo da Vinci (1452–1519), painter, sculptor, architect, engineer, musician and true scientist, studied the laws of falling bodies and solved the riddle of the fossils in the rocks. Still later Newton (1642–1727) established the law of gravitation, developed the calculus, put mechanics upon a solid basis and also worked out the properties of lenses and prisms so that his Optics (1704) will always have a prominent place in the history of science. From the time of the Renaissance on science grew steadily, but it was not till the latter half of the eighteenth century that the foundations in most of the lines recognized to-day were fully laid. Much of what was accomplished then is, at least, outlined in the chapters following.