  A stiff one-armed swimmer in glycerine goes nowhere, but if its arm is
elastic, exerting a restorative torque proportional to local curvature, the
swimmer can go on its way. Considering this happy consequence and the
principles of elasticity, we study a hyperdiffusion equation for the shape of
the elastica in viscous flow, find solutions for impulsive or oscillatory
forcing, and elucidate relevant aspects of propulsion. These results have
application in a variety of physical and biological contexts, from dynamic
biopolymer bending experiments to instabilities of elastic filaments.
