Low Temperature Magnetism -- I. Introduction -- II. Effects of magnetic and of electric fields on the energy levels of the magnetic ions -- III. Older research methods -- IV. Paramagnetic relaxation -- V. Paramagnetic resonance -- VI. Antiferromagnetism -- Adiabatic Demagnetization -- A. Fundamental considerations -- B. Experimental methods -- C. Magnetic investigations at relatively high temperatures -- D. Magnetic investigations at the lowest temperatures -- E. Other investigations below 1° K -- General references -- Superconductivity. Experimental Part -- I. Introductory survey -- II. Electrical and magnetic properties of macroscopic superconductors -- III. Thermodynamic properties of the normal and superconductive phases -- IV. Penetration of a magnetic field into a superconductor -- V. Phenomena associated with the surface energy between the superconductive and normal phases -- VI. Thermal effects -- VII. Superconductive alloys and compounds -- VIII. Diverse properties unchanged in the superconductive transition -- References Appended in Proof, March 1956 -- Theory of Superconductivity -- I. Introduction -- II. Thermodynamic properties and two-fluid models -- III. London theory and generalization -- IV. Boundary effects; the intermediate state -- V. Electron-phonon interactions -- General references -- Liquid Helium -- A. Historical survey -- B. The diagram of state -- C. Entropy -- D. Superfluidity -- E. Viscosity -- F. Heat conduction -- G. Wave propagation -- H. The saturated film -- J. The unsaturated film -- K. Theoretical Appendix -- Literature references -- Sachverzeichnis (Deutsch-Englisch) -- Subject Index (English-German).