Abstract: A universal measuring apparatus for the determination of rheological properties of viscous, viscoelastic and purely elastic materials measures said properties solely by axial movement of the mechanical measuring components of the apparatus ("axial rheometer"). the apparatus comprises a stiff metal frame (1, 2, 3) of which one horizontal part (3) is used as a mount for a force transducer (9) with little or practically no deflection at full scale load and on which an exchangeable piston-shaped holder (10) is mounted axially while the opposing part of the frame (1) forms a mount for a displacement transducer (4) of the micropositioner type which acts directly upon an axially moveable piston-shaped holder (6, 8), the micropositioner being able to cause an axial displacement and to continuously determine the axial position of the moveable piston-shaped holder (6, 8) with an accuracy of approximately 0.1 .mu.m, thereby producing a deformation in a sample (11) positioned between the sample holders (8, 10).