General view of first class operator Sylvester (Syl) Demskie weighing diazo and potassium chlorate in the mix house at the Hercules Powder Company plant in Port Ewen, New York. Diazo and potassium chlorate were two ingredients used in the explosive charge of the electric blasting caps manufactured at the plant. Notably, rubber was used to transfer and mix the explosive powder in order to avoid the hazard of metal, which might cause a spark or a shock.

Formed in 1912 as part of an anti-trust settlement with DuPont, the Hercules Powder Company (later Hercules Inc.) specialized in the manufacture of explosives and smokeless powders. The company's Port Ewen plant produced a range of special detonators designed for military use, as well as construction jobs that required blasts of dynamite, such as the clearing of quarries, mines, and tunnels.