Milestones to Modern Science 1543 Andreas Vesalius publishes unprecedented observations about the human body in De Fabrica. 1546 Girolamo Fracastoro proposes the idea that diseases can spread like seeds. 1599 Ulisse Aldrovandi publishes the first textbook of zoology. 1628 William Harvey publishes his work describing the blood's circulation and the heart's structure. 1650 Antony van Leeuwenhoek creates a microscope ten times more powerful than previous models. 1663 Robert Hooke discovers cells in a section of cork using a microscope. 1668 Francesco Redi disproves theories of spontaneous generation. 1674 Van Leeuwenhoek discovers bacteria using his microscope. 1701 Giacomo Pylarini gives the first smallpox inoculations to children in Constantinople. 1728 Pierre Fauchard describes how to fill teeth using tin, lead, and gold. Astronomy 1543 Nicolaus Copernicus publishes De Revolutionibus, laying out his heliocentric theory. 1572 Tycho Brahe observes a supernova in the constellation Cassiopeia. 1596 Johannes Kepler writes the first public defense of the Copernican system. 1608 Hans Lippershey and Zacharias Janssen patent original versions of the telescope. 1609 Kepler publishes his first two laws of planetary motion. 1630 Galileo finishes his Dialogue and obtains permission for its printing from the Vatican. 1688 Isaac Newton builds his first reflecting telescope. Physics and Chemistry 1591 Galileo demonstrates that the rate of a falling object does not depend on its weight. 1600 William Gilbert suggests the Earth behaves like a giant magnet with poles on opposite ends. 1649 Pierre Gassendi revives the idea that matter is made up of atoms. 1650 Otto von Guericke's air pump creates a vacuum between two hemispheres that even teams of horses can't pull apart. 1660 Royal Society founded 1687 Newton publishes his three laws of motion and the law of universal gravitation. 1704 Newton combines mathematics and experiments in his particle theory of light. World Events 1517 Martin Luther posts his ninety-five theses. 1555 Peace of Augsburg allows German rulers to determine their regions' religion. 1582 Pope Gregory XIII authorizes the calendar's reform based on Copernicus's theories. 1588 Britain defeats the Spanish Armada. 1611 King James Bible published 1618-1648 The Thirty Years War 1620 Pilgrims land at Plymouth. 1649 Charles I of England is beheaded by Oliver Cromwell. 1692 Witch trials held in Salem, Massachusetts. 1738 John and Charles Wesley experience their evangelical conversions. .