the plate from the actuator 18 during the test the samples 12 and 14 are positioned adjacent the top and bottom surfaces 24 and 26 of the loading plate 16 but are each permitted to deform about a vertical axis normal to the loading plate as the plate moves transversely the surfaces 24 and 26 of the loading plate the stationary member 22 and the piston 20 that contact the ends of the samples 12 and 14 are roughened so that the sample is frictionally held against free transverse movement during testing each sample 12 14 is confined within a stack of teflon coated steel rings 50 as the loading plate 16 moves transversely the rings 50 slide on each other to permit deformation of the samples 12 and 14 at the inner ends of the samples 12 and 14 the rings 50a closest to the loading plate 16 are positioned by short annular walls 52 and 54 that surround the upper and lower loading plate surfaces 24 and 26 the rings 50b at the outer ends of the stacks are positioned by similar annular walls 56 and 58 carried by the piston 20 and the stationary member 22 respectively the rings 50a and 50b interlock loosely with the annular walls 52 54 56 and 58 permitting sufficient transverse movement that the samples 12 and 14 are held during testing by friction alone it will be apparent that the readings obtained by monitoring the outputs of the transducers 32 44 and 46 give an indication of soil response that is substantially uneffected by the characteristics of.