Prof. E. H. Hall

Abstract

PROF.EDWIN HERBERT HALL, emeritus professor of physics in Harvard University, whose death occurred on November 20, devoted most of his life to the study and investigation of electric conduction. He will doubtless be most remembered by the Hall effect which he discovered in 1878. This effect is the production of an electromotive force when an electric current flows across the lines of force of a magnetic field. This electromotive force is perpendicular both to the magnetic field and to the electric current or, speaking more generally, it is proportional to the vector product of the last two quantities. Other aspects of electrical conduction to which Hall made contributions include the Thomson effect in soft iron, thermo-electric heterogeneity in different metals, the theory of thermo-electric action and of thermal conduction in metals and the relations of the four transverse effects of the magnetic field (the Hall effect was the first of these to be discovered). His keen interest in this field was maintained to the end of his life. In fact, a book entitled “A Dual Theory of Conduction in Metals”, in which he summarizes his considered views on the subject, has recently appeared.