An attempt, not wholly successful to give the average reader an understanding of modern physics. The book demands hearty cooperation on the part of the reader. Quite simply, at first, the author takes his readers into the world of molecules and introduces him to a universe where all movement is governed by the laws of chance. Temperature and its basic connection with motion of molecules -- the methods by which speed and size are estimated -- the count -- subdivisions into atoms -- moles and atomic weights. Then on to the theory of the ultimate atom -- the cathode rays -- the discovery of the electron. The Einstein theory of relativity -- the quanta theory -- photo-electric cells -- the spectra of gases -- the structure of matter. Radioactivity -- the law of disintegration. Internal structure and characteristics of the atom. The Restless Universe is supposedly for the layman, but the slightly interested reader would find it hard going. It necessitates some background for any reading other than hard work. Place comparative in the field of physics to Sir James Jeans' The Universe Around Us in the field of astronomy.