Since Gasser and Erlanger (3, 4) published their extensive experiments on the relationship between the conduction-rate and the diameter of the nerve fibre, there has been a large amount of work concerning this problem (Blair and Erlanger, 2; Zotter man, 15; Pumphrey and Young, 9; Hursh, 7; Gasser and Grundfest, 6 etc.). The method adopted by these investigators, except for Pumphrey and Young wh...