as he later declared – into separate portions. This was the birth of quantum physics. New structure and new physics In 1914, the PTR President Emil Warburg discontinued the subdivision into a physical and a technical division and re-structured the PTR into divisions for optics, electricity and heat, with sub-divisions of a purely scientific and technical nature. Under Warburg's successor Walther Nernst, the Reichsanstalt für Maß und Gewicht (Imperial Institute for Weights and Measures – RMG) was, in addition, integrated into the PTR. A newly established division took over from the RMG extensive tasks with regard to the verification system as well as the measurements of length, weight and volume associated with the verification system. The profile of tasks was thus similar to that of PTB today: Through its own research and development, and through services building on this, the PTR was to ensure the uniformity of metrology and its continuous further development. As regards contents, the PTB was dedicated at that time to the so-called New Physics. This included, among other things, research on the newly discovered X-rays, new atomic models, Einstein's Special Theory of Relativity, quantum physics (based on the already mentioned work on the black-body radiator), and the investigation of the properties of the electron. Scientists like Hans Geiger, who established the first radioactivity laboratory of PTR, were involved in this research work. Walther Meißner succeeded in liquefying helium, which led him to the discovery of the superconductivity of a series of metals. In this connection, he recognized some years later – together with his colleague Robert Ochsenfeld – that superconductors have the property of displacing from their interior a magnetic field which has been applied from the outside – the Meißner-Ochsenfeld Effect. Nazi Germany With the appointment of Johannes Stark as president on 1 May 1933, the ideology of National Socialism found its way into the PTR. The convinced advocate of a German Physics terminated diverse research projects on issues of modern physics to which he referred to as "Jewish", among them, in particular, works on quantum physics and on the theory of relativity. Stark also tried to enforce the "Führer principle" (Führerprinzip) at the PTR: in 1935, he dissolved the Kuratorium and took over its competences himself. Jewish employees and critics of the NSDAP (such as Max von Laue) were dismissed. After World War II, Von Laue participated in the re-founding of PTB. Albert Einstein,