The spring comprises layers of resilient material connected and spaced apart by compression members. The compression members are also spaced apart and indexed so that those between one pair of layers are located opposite the spaces between the compression members between the adjacent pair of layers. Springs of various shapes and areas are cut from sheets of spring structure and the spring rates are expressed in terms of pounds per inch per square inch of spring work area. Spring rates range from 1000 to 1250 pounds per inch per square inch of spring. Work capacities range from 13 to 120 inch pounds per square inch of spring. Ratios of work capacity to weight range from about 200 for springs about 1/4 inch thick to 600 for springs 3/4 inch thick. The cavities in the springs are vented to ambient to enhance linearity and efficiency.