General view of an unidentified employee making an adjustment to the lower part of a hydrochlorinator unit at the Hercules Powder Company plant in Parlin, New Jersey. Per notations accompanying the photograph, the hydrochlorinator was used to introduce anhydrous hydrogen chloride, also known as hydrogen chloride gas, during the production of Pentaerythritol Trichloro Monoacetate, a key intermediate useful in the production of films, filaments, and plastics.

Formed in 1912 as part of an anti-trust settlement with DuPont, the Hercules Powder Company (later Hercules Inc.) initially specialized in the manufacture of explosives and smokeless powders and subsequently diversified its business to encompass a variety of industrial products, including pine and paper chemicals, synthetics, pigments, polymers, and cellulose.