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T
he Islamic Golden Age was a great flowering of the sciences and arts that began in the capital of the Abbasid Caliphate, Baghdad, in the mid-8th century and lasted for about 500 years. It laid the foundations for experimentation and the modern scientific method.In the same period in Europe, however, several hundred years were to pass before scientific thought was to overcome the restrictions of religious dogma.
Dangerous thinking
For centuries, the Catholic Church’s view of the universe was based on Aristotle’s idea that Earth was at the orbital center of all celestial bodies. Then, in about 1532, after years of struggling with its complex mathematics, Polish physician
Nicolaus Copernicus completed his heretical model of the universe that had the Sun at its center. Aware of the heresy, he was careful to state that it was only a mathematical model, and he waited until he was on the point of death before publishing, but the Copernican model quickly won many advocates.
German astrologer Johannes Kepler refined Copernicus’s theory using observations by his Danish mentor Tycho Brahe, and calculated that the orbits of Mars and, by inference, the other planets were ellipses.
Improved telescopes allowed Italian polymath Galileo Galilei to identify four moons of Jupiter in 1610. The new cosmology’s explanatory power was becoming undeniable.
Galileo also demonstrated the power of scientific experiment, investigating the physics of falling
objects and devising the pendulum as an effective timekeeper, which Dutchman Christiaan Huygens used to build the first pendulum clock in 1657. English philosopher Francis Bacon wrote two books laying out his ideas for a scientific method, and the theoretical groundwork for modern science, based on experiment, observation, and measurement, was developed.
New discoveries followed thick and fast. Robert Boyle used an air pump to investigate the properties of air, while Huygens and English physicist Isaac Newton came up with opposing theories of how light travels, establishing the science of optics. Danish astronomer Ole Rømer noted discrepancies in the timetable of eclipses of the moons of Jupiter, and used these to calculate an approximate value
INTRODUCTION
Francis Bacon publishes Novum Organum Scientarum and The New Atlantis, outlining the scientific method.
Astronomer William Gilbert publishes De Magnete, a
treatise on magnetism, and suggests that Earth is a magnet.
Johannes Kepler suggests that Mars has an elliptical orbit.
Robert Boyle publishes New Experiments Physico-Mechanical:
Touching the Spring of the Air, and its Effects, investigating air pressure.
Galileo observes the moons of Jupiter and experiments with balls
rolling down slopes.
Nicolaus Copernicus publishes De Revolutionibus Orbium
Coelestium, outlining a heliocentric
universe.
Evangelista Torricelli invents the barometer.
Jeremiah Horrocks observes the transit
of Venus.
1660
Sfor the speed of light. Rømer’s compatriot, Bishop Nicolas Steno, was sceptical of much ancient wisdom, and developed his own ideas in both anatomy and geology.
He laid down the principles of stratigraphy (the study of rock layers), establishing a new scientific basis for geology.
Microworlds
Throughout the 17th century, developments in technology drove scientific discovery at the smallest scale. In the early 1600s, Dutch eyeglasses-makers developed the first microscopes, and, later that century, Robert Hooke built his own and made beautiful drawings of his findings, revealing the intricate structure of tiny bugs such as fleas for the first time. Dutch fabric-store owner
Antonie van Leeuwenhoek, perhaps inspired by Hooke’s drawings, made hundreds of his own microscopes and found tiny life forms in places where no one had thought of looking before, such as water. Leeuwenhoek had discovered single-celled life forms such as protists and bacteria, which he called “animalcules.”
When he reported his findings to the British Royal Society, they sent three priests to certify that he had really seen such things. Dutch microscopist Jan Swammerdam showed that egg, larva, pupa, and adult are all stages in the development of an insect, and not separate animals created by God.
Old ideas dating back to Aristotle were swept away by these new discoveries. Meanwhile, English biologist John Ray compiled an
enormous encyclopedia of plants, which marked the first serious attempt at systematic classification.
Mathematical analysis Heralding the Enlightenment, these discoveries laid the groundwork for the modern scientific disciplines of astronomy, chemistry, geology, physics, and biology. The century’s crowning achievement came with Newton’s treatise Philosophiæ Naturalis Principia Mathematica, which laid out his laws of motion and gravity. Newtonian physics was to remain the best description of the physical world for more than two centuries, and together with the analytical techniques of calculus developed independently by Newton and Gottfried Wilhelm Leibniz, it would provide a powerful tool for future scientific study. ■
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In Micrographia, Robert Hooke introduces the world
to the anatomy of fleas, bees, and cork.
Nicolas Steno writes about solids (fossils and
crystals) contained within solids.
Jan Swammerdam describes how insects develop in
stages in Historia Insectorum Generalis.
Ole Rømer uses the moons of Jupiter to show that light has
a finite speed.
John Ray publishes Historia Plantarum, an
encyclopedia of the plant kingdom.
Antonie van Leeuwenhoek observes
single-celled organisms, sperm, and
even bacteria with simple microscopes.
Christiaan Huygens first announces his wave theory of light, which
will later contrast with Isaac Newton’s idea of light as corpuscular.
Isaac Newton outlines his laws of motion
in Philosophiae Naturalis Principia
Mathematica.