Excerpt:
The transitional period falls between the pre 17th century alchemy and the 18th century chemistry. The climax of this period is probably with the English scientist Isaac Newton (1642 - 1727) and his book "Principia Mathematica" (1687). In this book, Newton introduced three laws of motion which served well for over two centuries in mechanical sciences. He also expanded his theories of gravitation and provided some useful explanations of the work of the Italian Scientist Galileo Galilei (1564 - 1642) who in the 1590's studied the behavior of falling bodies.