Part 1 of the thesis contains a brief but necessary presentation of the kinomatics of planar linkage mechanisms. In Part II the dynamics of planar linkage mechanisms is examined using the formulae derived in part I to evaluate pin-forces developed due to the inertia of the links themselves. In Part III the operation of motion is derived and, subject to certain linearizing assumptions, is found to be a special type of Hill's equation. Part IV deals with the experimental investigations carried out in association with the theoretical work of Part III.