Page:Popular Science Monthly Volume 37.djvu/860

 to account for the structure of the universe, are contained in this work. The first of the three laws affirms that every body, so far as it is unaffected by extraneous causes, always perseveres in the same state of motion or rest; and the second that simple or elementary motion is always in a straight line. "These doctrines of inertia, and of the composite character of curvilinear motion," says Mr. Wallace, "were scarcely apprehended even by Kepler or Galileo; but they follow naturally from the geometrical analysis of Descartes." He taught that extended matter has no limits to its extent, though the power of God has divided it by lines discriminating its parts in endless ways. He denied the possibility of a vacuum, and the existence of atoms or ultimate particles, and regarded matter as uniform in character throughout the universe—all of which views are consistent with what may be logically deduced from the results of the latest investigations. In the universe packed with matter, no particle can move unless all the others move too. Hence we have universal motion, taking the form of "a host of more or less circular movements, and of vortices or whirlpools of material particles, varying in size and velocity." These vortices, which were supposed to give rise to three kinds of matter and to the phenomena of radiating light, were made to account for the existence and motions of all the stars and systems, the sun and planets, and the earth. Descartes applied his vorticellar theory not only to all the phenomena of physics, but also to those of organic life, including that in animals and man; whence he ventured to show that man and the animals are really machines, with the single difference that man has a rational soul, while the animals have not. In the Treatise on Man and the Formation of the Foetus, which was published after his death, Descartes expounded the doctrine of animal spirits. Other works are the Treatise on the Passions of the Soul, which was translated into French for Madame Elizabeth, Princess Palatine; and the Rules for the Direction of the Mind, a posthumous work. Descartes was never married, but he is believed to have had a natural daughter, Francine, who died when she was five years old. He is described as having been "a little man, with a large head, projecting brow, prominent nose, and eyes wide apart, with hair coming down almost to his eyebrows," and feeble voice, and as usually dressed in black.

On his death, Queen Christina wanted him buried with the kings of Sweden; but Chanut, who is supposed to have carried out his wishes, had his body modestly interred in the cemetery of the Orphans' Hospital, where Catholic foreigners were usually buried. Thence his remains were a few years afterward transferred to France, where, after several changes, they were finally deposited, in 1819, in the Church of Saint Germain des Prés.