Fig. 3. Force transfer from the tarsus to the coxa of a locust middle leg. (A) A piezo-ceramic tongue bends during a 2 ms ramp (and hold) voltage step and indents the tarsus at one pulvillus with a force of 0.1 mN locally. The connected force transducer records the tension (lower trace in the centre) where the stimulus is applied, while the upper transducer, with the coxa glued onto it, records the transferred tensile force (upper trace in the centre; averaged 64x) after a latency of less than 1 ms. Arrows indicate direction of forces. (B) Recording afferents with a suction electrode from nerve stump from the antero-dorsal groups of trochanteral sensilla trCS1–3 while applying an antero-dorsally directed ramp stimulus (arrow) of approximately 0.1 mN to a proximal (posterior) pulvillus. (C) Recording as in B but over a larger time-scale and averaged 64x. The first afferent spikes arise 3 ms after the start of ramp stimulus [arrowheads mark electrical artefacts (art.) from the ramp generator].