[en] This paper presents a summary and evaluation of the experimental properties of superfluid ³He as they were known in the fall of 1974. Subjects having thermodynamic significance, including specific heat, static magnetism, phase equilibria, and superfluid density, are discussed first. Then known flow properties are treated. After a brief discussion of the theoretical ideas which motivated some of the later experiments, the subject of dynamic magnetism is reviewed. Closely related work in a magnetic field in the immediate temperature region of the critical temperature is discussed, as are the propagation of ultrasound, the phenomena of supercooling and superheating, precise indication of the critical temperature, and the effects of certain restrictive geometries. The article concludes with a brief discussion of some new developments which appeared after the main text was finished. Appendices on thermometry and on parameters of the normal Fermi liquid are included