c. 1920's or 1930's original university of chicago chemistry research laboratory ammonium hydroxide reagent bottle designed and fabricated by or for the corning glass works, corning, ny. the nicely aged vintage american medical clear glass bottle contains the chemical systemic name and formula in the form of embossed letters along the front side. the "penny" style ground glass stopper may or may not be original to the bottle, but is of the period. the interior content or fluid (most were empty) was removed and thoroughly cleaned inside and out. several reagent bottles and other chemistry glassware were removed from university of chicago laboratories.