Abstract: A metrological instrument includes an inductive transducer having a stylus, all being disposed within a protective housing. Upon initiation of the measuring operation, the transducer is moved so that the stylus moves round an endless path such that the stylus is first projected at a high speed from the housing, is thereafter moved to engage the workpiece surface, is then moved at relatively slow speed across the workpiece surface for performing the measurements, and, following completion of the latter movement, is retracted at a high speed into the housing. These movements are effected by a series of cams driven by a single motor. Such an instrument may be located next to a production line without risk of damage and may used for the checking of each of a multiplicity of identical components produced in a mass production process.