hard to find all original and fully functional american depression era dental office stationary four-legged "set-ezy" examination stool with unusual patented spring suspension seat. the earliest version or configuration of this stool was designed and patented in 1921 by charles e. miller of columbus, oh. the examination stool was fabricated, beginning in the 1920's, by the hamilton mfg. co., two rivers, wisc., and was a popular fixture used in medical and dental examination rooms throughout the country. the inclusion of spring-loaded system for supporting a stool seat was originally intended for use with a street car or other moving vehicles where vibrations and jarring would be absorbed and provide added comfort to the vehicle operator. the plurality of springs are integrated with a rigid, four-legged angled iron base with all-welded joints. the fully adjustable stool contains a single threaded steel spindles the revolves one war or the other to achieve the desired height. the radially extended springs are attached to a set of centrally located heavy gauge steel plates containing openings for the threaded spindle. the oversized spring in the center provides vertical cushioning, while the 12 coil springs are designed to support the load and provide free forward or lateral movements. the stool seat moves when one moves so that one can remain "comfortably suspended" for prolonged periods of time. the metal stool frames were typically finished in a baked black or olive green enameled finish. a cushioned dupont black "fabrikoid" seat was optional. the original cushioned seat has been saved, but switched out with a solid maple wood seat for added contrast between the materials and visual character. the aluminum tag on the underside of the original, cushioned seat is perfectly intact. the all-metal stool frame has been brushed down to bare metal and sealed with a clear coat lacquer.