RT Journal T1 AN introduction to the science of radio-activity. JF Journal of the American Medical Association JO Journal of the American Medical Association YR 1909 FD August 7 VO LIII IS 6 SP 474 OP 474 DO 10.1001/jama.1909.02550060050022 UL http://dx.doi.org/10.1001/jama.1909.02550060050022 AB This is an elementary treatise on the physics of radioactivity. It begins with an introductory chapter on the discovery and development of our knowledge of radioactivity. The work proper is divided into three parts. Part I presents in several chapters a description of the radioactive elements and of the phenomena of radioactivity; Part II is an exposition of the theories which explain the phenomena of radioactivity; and Part III considers the practical application of radioactive energy in physical experiments. This plan lends itself to a clear and very interesting development of the subject. The work is frankly offered as an elementary treatise, but it will be found by the student to be a full and satisfactory work. It is hard to imagine a more fascinating chapter in science than that dealing with the physics of radioactivity. It has not overthrown our previous theories of matter and energy—rather it has confirmed