
Typical apparatus as shown in FIGS. 1 and 12 for indicating the relative positions in a given direction between a reference point (24,59) and a test point (29,68) spaced therefrom and movable relative thereto is useful for measurement of the magnitude and direction of static or dynamic torque in a shaft (8). Overlapping transparent reference (20,60) and test surfaces (25,61), either parallel disks (60,61) or coaxial cylinders (20,25) each having a relevant portion covered with a plurality of equ...











