Optics

Isaac's initial lectures as Lucasian Professor dealt with optics, including his great discoveries made

during the plague years. Isaac reached a conclusion that white light light is not as simple as it seems,

as Philosophers thought just like Aristorale had believed. When he passed a thin beam of sun light

through a glass prism, he recorded that he saw a spectrum of colors--red, yellow, green, blue, and

violet that formed on the wall. This showed that the light was too long to be explained by the

accepted theory of the bending light by dense media. His old theory was that any light that passed

through a prism at the same angle would reflect and give off the same colors of light that represent

the structure of the original color. Isaac disapproved his original theory of light travel by retesting

his theory with colleagues and found out that each light is refracted just a little different that before.

Isaac discovered the law of gravitation in 1666, also Isaac discovered the law stating the centrifugal

force of a body moving uniformly in a circular path. Isaac still thought the motions of the planet

may be caused by the actions of whirlpools, or vortices, of small corpuscles. He thought of circular

motion as the result of a balance between two forces, one centrifugal, the other centrifical.