newton
... 1661, Trinity College at Cambridge admitted Newton as a subsizar, a student required to perform various domestic services. He studied arithmetic, geometry, trigonometry, astronomy, and optics. Newton earned his bachelor’s degree in January 1665. In 1665 Newton returned to Woolsthorpe. During this time, Newton made progress in what he called his mathematical “method of fluxions,” which is now calculus. He also recorded his first thoughts on gravitation by observing the fall of an apple in an orchard. The fall of an apple led him to think that the attractive gravitational force acting on the apple might be the same force acting on the moon. Newton believed that this force held the moon in orbit. Newton also began to investigate the nature of light. He concluded that sunlight is a combination of all the colors of a spectrum and that the sunlight separates when passed through a prison because its component colors are differing refrangibility, the ability of light waves to be bent by a substance. This property depends on the wavelengths of the different compounds of sunlight. A refracting substance will bend each wavelength of light by a different amount. In October 1667, Newton began to examine telescopes. Newton was convinced that a telescope resolution is limited not so much by the difficulty of building flawless lenses as by the general refraction differences of various colored rays...