Newton's Laws by Professor Raymond Flood

In his Principia Isaac Newton used his law of universal gravitation and three laws of motion to explain elliptical planetary motion, the orbits of comets, the variation of the tides and the flattening of the earth at its poles. Further important work on celestial mechanics was undertaken by Joseph-Louis Lagrange, Pierre-Simon Laplace and Henri Poincare. It was Poincare who discovered that even with Newton's deterministic laws the resulting motion may be irregular and unpredictable, the basis of modern day chaos theory. (from gresham.ac.uk)

Related Links
Books and Films - Isaac Newton