The Wave-lenght of the soft gamma Rays from Radium B (In collaboration with E.N. da C. Andrade).

London, 1914. Without wrappers, but stitched. In "Philosophical Magazine and Journalof Science", Vol. 27, No. 161. May 1914. Pp. 757-916 a. 6 plates.(= the whole issue No 161). Rutherford's paper: pp. 854-860 a. 1 plate. First edition, finally establishing the nature of Röntgen's X-Rays.In 1900 "Villardhad discovered gamma gamma-rays. He noted at once that these rays are not deflected by magnetic fields. Two years later Rutherford suggested that gamma-rays might be very hard form of beta-rays. This view became less and less tenable.(and) slowly the evidence grew that gamma-rays and X-rays were akin, but a lately as 1912 Rutherford still wrote with a touch of caution: "There is at present nodefinite evidence to belive that X-rays and gamma-rays are funamentally different kindsof radiation". he matter was finally settled fourteent years after the first observatiob of gamma-radioactivity, when Rutherford and Andrade observed reflexion of gamma-rays from crystal force (in the paper offered here)." (Pais. Inward Bound p. 62.).The issue contains further importent papers in first editions. W.H. BRAGG. The Intensity of Reflexion of X Rays by Crystals. Pp. 881-99. This is an account of his famous work on X-ray spectroscopy.E. MARSDEN: The Passage of alpha Particles through Hydrogen. Pp. 824-830. Here he discovered that when alpha-particles were projected into hydrogen, so that the heavy projectiles struck lighter atoms, a few of the hydrogen atoms were driven forward far beyond the range of the alpha particles.J.J.THOMSON: The Forces between Atoms and Chemical Affinity. Pp. 757-789.…