original c. 1940's american industrial four-legged stationary hospital examination room adjustable height stool fabricated by or for the national mineral company, chicago, il. the stool contains a newly added revolving seat comprise of solid maple wood with stained and sealed finish. traces of the original chrome-plated finish over tubular steel remains partially intact. the solid threaded steel spindle rotates up and down manually. measures approximately 21 inches high fully extended with a 14 inch seat diameter.