Vibratory separating apparatus wherein the screen basket assembly is mounted on the base by mounting means including resilient elements which are resilient laterally and longitudinally to be longitudinally extensible and compressible to permit orbital vibrating movement of the assembly relative to the base. The orbital vibrating movement is created by vibration generating means including rotatably driven eccentric means; and mounting means are provided for mounting the vibration generating means at a plurality of alternative positions adjusted longitudinally of the screen whereby the rate of advance of material longitudinally along the screen feed face by orbital vibrating movement of the screen is adjustable independently of the intensity and the amplitude of the vibrations by varying the location at which the vibration generating means is mounted by the mounting means.