‎"RÖNTGEN, WILHELM CONRAD & HEINRICH HERTZ. - HERTZ'S PRINCIPLE OF THE UNITY OF ELECTRIC FORCE.‎
‎Neue Versuche über die Absorption von Wärme durch Wasserdampf. 2 Parts. (+ Hertz:) Ueber die Beziehungen zwischen den Maxwellschen electrodynamischen Grundgleichungen und den Grundgleichungen der gegnerischen Electrodynamik.‎

‎Leipzig, Johann Ambrosius Barth, 1884. Contemp.hcalf. Raised bands, gilt spine. Spine very slightly rubbed. Small stamp on htitle, title and verso of titlepage.""Annalen der Physik und Chemie. Hrsg. von G. Wiedemann"". Neue Folge Bd. 23. VIII,696 pp. and 8 folded plates. Röntgen's paper: pp. 1-40 a. 259-298, 2 folded plates. - Hertz's paper: pp. 84-103. Clean and fine.‎

Reference : 43172

‎First printing of Röntgen's early paper on the heat absorption in vapor. ""Having constructed a very sensitive air thermometer, he was able to measure the absorption of heat in water vapor, and his flair for experiment was also shown by his work on the compressibility of liquids and solids.""(DSB XI, p.530).An. HERTZ'S paper: This is a major paper by Hertz in which he gives simple proofs of Maxwell's fundamental equations. ""In 1884, at Kiel, Hertz had already carried out a study of Maxwell's theory. It was a theoretical response to Helmholtz' general problem of deciding between the electrodynamical theories. Whereas Helmholtz had shown that the experimental decision lay with unclosed currents, Hertz showed that a theoretical decision could be made on the basis of predictions for closed currents. Hertz proved that Maxwell's equations were compatible with the physical assumptions shared by all electrodynamical theories and that the equations of the contending theories were not. He concluded that if the choice lay solely between Maxwell's equations and the equations of the other type of theory, then Maxwell's were clearly preferable."" (DSB VI, pp. 344-45).The volume contains also an importent paper by OTTO RICHARD LUMMER his Inauguraldissertation: ""Über eine neue Inteferenzerscheinung an Planparallelen Glasplatten und eine Methode, die Planparallelität solcher Gläser zu prüfen"". Pp. 40-84 a. 1 plate. and ""Ueber eine neue Inteferenzerscheinung."" pp. 513-548. - Also papers by Kundt, Kohlrausch, Weber and others.‎