  Lanczos's quaternionic interpretation of Dirac's equation provides a unified
description for all elementary particles of spin 0, 1/2, 1, and 3/2. The
Lagrangian formulation given by Einstein and Mayer in 1933 predicts two main
classes of solutions. (1) Point like partons which come in two families, quarks
and leptons. The correct fractional or integral electric and baryonic charges,
and zero mass for the neutrino and the u-quark, are set by eigenvalue
equations. The electro-weak interaction of the partons is the same as with the
Standard model, with the same two free parameters: e and sin^2 theta. There is
no need for a Higgs symmetry breaking mechanism. (2) Extended hadrons for which
there is no simple eigenvalue equation for the mass. The strong interaction is
essentially non-local. The pion mass and pion-nucleon coupling constant
determine to first order the nucleon size, mass and anomalous magnetic moment.
