This work, written for a wide audience of students and general readers, details the chaos produced in the physics community at the beginning of the 20th century by groundbreaking experimental findings and the theoretical speculations they engendered. It traces the slow and difficult birth of a new scientific order that resulted from the work of many of this century's most distinguished scientists, including Max Planck, Albert Einstein, Ernest Rutherford, and Niels Bohr. Comparable in its impact to the scientific upheavals initiated by Galileo and Newton in the 17th century, and to the advent of Darwin's theory of evolution, this emerging science - based on newly developed experimental techniques - exposed the flaws in the well-established and cherished view of the world as described by classical physics.In telling this story, the author describes the essential features of quantum physics, what sets it apart from the classical view of the mechanical universe, and how the new science has led to unprecedented advances in understanding the essence of matter and the forces of nature. As a special feature, the author has presented mathematical details in separate boxed sections where they can be studied by readers interested in deeper insight, or skipped without any interruption to the flow of the narrative. The book is thus accessible to nonscientist general readers who will find it an ideal guide to the breathtaking discoveries of modern science that have so profoundly altered our perceptions of the material world. Read more... 1. The Old Order: Classical Physics. From Galileo and Newton: Classical Mechanics. From Oersted and Faraday: Electromagnetism. From Rumford and Carnot: Heat and Thermodynamics. From Daniel Bernoulli and Joule: Kinetic Theory and Statistical Physics. From Fraunhofer and Kirchhoff: Radiation and Heat. 1895 -- 2. Clouds on the Horizon. The Last Stand Against Atoms and Molecules. Troubles with the Atomic Description of Heat. The Connection Between Matter and Radiation. New Rays Are Seen: Cathode and Canal Rays. An Elusive Ether -- 3. The Entrance of the Electron. e/m for the Cathode and Canal Rays. The Ionic Charge e. A Universal Constituent of Matter. Brownian Motion: A Determination of k -- 4. A Chaotic Period Begins. Particles and Fields. Blackbody Radiation According to Wien. The Experimental Verdict. Blackbody Radiation According to Planck; the Appearance of h -- 5. Allergic Reactions to h. An Initial Lack of Interest. The Radiation Quantum Appears, Is Rejected