Hall wax was a student of Heinrich Hertz. In 1886 he had discovered the external photoeffect. Hall wax continued the Hertzian investigations 1887. Due to its results the outer photoelectric effect has long been named as Hall wax effect.
With the study of the photoelectric effect, he laid the foundation for the development of the photoelectric cell, the photo- electricity and the light quantum hypothesis of Albert Einstein ( see also photon).
- The light electricity. In: Handbook of Radiology, Vol 3, Leipzig 1916, pp. 245-563.