In 1665 England is stricken by the final waves of the bubonic plague. Cambridge university closes down to avoid plague and a young Isaac Newton returns to Woolsthorpe, his family home in the country side. For the next 18 months Isaac Newton made discoveries that would define the rest of his scientific life, especially his work in optics.
Since the time of Aristotle, great thinkers believed that white light was pure. Colored light was created by altering white light, hence a prism creates different colors by internally altering pure light. Newton, incredulous, devices a test of his own. By passing sunlight through a prism he produces a spectrum of colors. However when passing red light through a second prism, it remains red. Since red light was not altered, white light had to be a combination of colored light.
As the plague subsides, Newton returns to Cambridge in 1667. There, Newton notices that the edges of telescope lenses acted like prisms thereby falsely coloring objects being observed. To solve this Newton uses a series of mirrors rather than lenses. This not only removes false colorizations, it also makes his reflecting telescope much shorter then conventional refracting telescopes. To Newton’s dismay, his telescope made him famous throughout the scientific community and in 1672 he was elected member of the Royal Society. That same year Newton publishes his first paper on colors.
Newton’s eighteen months at Woolsthorpe were legendary. His insights on intervals almost as small as zero became the foundations of infinitesimal calculus. His understanding of forces and gravity becomes the cornerstone of his Magnus Opus the “Principia” (published in 1689). He would later be elected as President of the Royal Society in 1703 as well as serving as a member of parliament in 1689 and 1701. Though well honored and distinguished, Sir Isaac Newton publishes his second major work “Opicks” in 1704, long after his initial discoveries at his home in Woolsthorpe.
Special thanks to Fran May for the featured image