Cathode Rays. [in] The London, Edinburgh, and Dublin Philosophical Magazine: THE DISCOVERY OF THE ELECTRON

J J Thomson announces the discovery of the first sub-atomic particle, the electron, in this journal article published in the Philosophical Magazine in October 1897.

Bound together as Volume XLIV, 44 - Fifth Series - for the period July-Decembe 1897, this volume has been deaccessioned from the library of Venice's Istituto Veneto Scienze Lettere e DArti - small oval stamp at the tail of the title page only. Small shelfmark label: 'Periodici B. 171' to the tail of the front pastedown. Bound in half sheep over handsome marbled boards, gilt decoration to spine and a second 'Periodici' paper label at the tail of the backstrip. Some browning to margins of end leaves, otherwise a near fine copy.

Thomson's ground breaking paper occupies pp. 293-316, of Vol. 44, no. 269 (October 1897) of this volume. It is preceded by a sequence of fold-out diagrams from a previous paper. In 1897 Thomson solved the riddle about the nature of cathode rays by proving that the they consist of negatively charged particles, the mass of which is 1,800 times smaller than that of the hydrogen atom and thereby became the discoverer of the electron, which he called the "corpuscle" until 1907. The consequence of Thomson's discovery was that there was no longer an 'indestructible' atom, and it become probable that the general building material of all matter was a form of energy: 'Thomson's discovery presented almost every branch of physics with new tasks and opened up new Research Areas.' (Printing and the Mind of Man). PMM 386 (a)