The Pack House

The Pack House. . This photograph, taken circa 1903, shows one of two Pack Houses at the California Powder Works. In this building, located where 267 Keystone is today, 25 and 50 pound cans of black powder were packed and readied for shipment. Before the mid 1870s, wooden kegs, made by Chinese workers, were used to ship powder. However, wooden barrels were relatively fragile and when handled improperly, would crack letting in moisture which made the powder less effective. When can-making machinery became available, the Powder Works replaced the wooden kegs with tin ones thus increasing the safety and reliability of the gunpowder., The two fellows standing in the doorway wearing the shiny aprons are covered in graphite. Graphite, a lick dry form of carbon, was added to the finished powder to keep it from clumping. During the packing process, powder dust often sifted onto the floor; therefore, as a safety precaution, floors were regularly swept and brushes were provided at each door for workers to clean their shoes before entering. If someone walked into the Pack House with grit on their boots, they could easily ignite the powder dust on the floor, much like striking a match. Shoes made with tacks or nails were also forbidden at the Powder Works for the same reason. The possibility of creating accidental sparks around gunpowder was a constant concern during the manufacturing process. Fortunately, the Pack House was one location where no recorded flash fires or explosions ever occurred.