early Renaissance, with polymath artists such as Leonardo da Vinci making observational drawings of anatomy and nature. Da Vinci set up controlled experiments in water flow, medical dissection, and systematic study of movement and aerodynamics, and he devised principles of research method that led Fritjof Capra to classify him as the "father of modern science". Other examples of Da Vinci's contribution during this period include machines designed to saw marbles and lift monoliths, and new discoveries in acoustics, botany, geology, anatomy, and mechanics. A suitable environment had developed to question classical scientific doctrine. The discovery in 1492 of the New World by Christopher Columbus challenged the classical worldview. The works of Ptolemy (in geography) and Galen (in medicine) were found to not always match everyday observations. As the Reformation and Counter-Reformation clashed, the Northern Renaissance showed a decisive shift in focus from Aristotelean natural philosophy to chemistry and the biological sciences (botany, anatomy, and medicine). The willingness to question previously held truths and search for new answers resulted in a period of major scientific advancements. Some view this as a "scientific revolution", heralding the beginning of the modern age, others as an acceleration of a continuous process stretching from the ancient world to the present day. Significant scientific advances were made during this time by Galileo Galilei, Tycho Brahe, and Johannes Kepler. Copernicus, in De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres), posited that the Earth moved around the Sun. De humani corporis fabrica (On the Workings of the Human Body) by Andreas Vesalius, gave a new confidence to the role of dissection, observation, and the mechanistic view of anatomy. Another important development was in the process for discovery, the scientific method, focusing on empirical evidence and the importance of mathematics, while discarding much of Aristotelian science. Early and influential proponents of these ideas included Copernicus, Galileo, and Francis Bacon. The new scientific method led to great contributions in the fields of astronomy, physics, biology, and anatomy. Navigation and geography During the Renaissance, extending from 1450 to 1650, every continent was visited and mostly mapped by Europeans, except the south polar continent now known as Antarctica. This development is depicted in the large world map Nova Totius Terrarum Orbis Tabula made by the Dutch cartographer Joan Blaeu in 1648 to commemorate the Peace of Westphalia. In 1492, Christopher Columbus sailed across the Atlantic Ocean from Spain seeking