Close-up view of assorted valves, pipes, and fittings at the Hercules Powder Company plant in Parlin, New Jersey. Per notations accompanying the photograph, this system, which was used to handle hydrochloric acid, was lined with Penton, a Hercules-branded chlorinated polyether used as an ingredient in protective coatings for structural steel and other metals, papers, cardboard, 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.