The Shelton-Payne Arms Company inside the Merrick Building played an important role in supplying arms and ammunition to all factions of the revolution. Arms-dealing was a very profitable business in El Paso during Mexican Revolution. In December 1910, Mexican government agents reported that Abraham González ordered 60,000 cartridges from the Shelton- Payne Arms Company and sent them across the border to the Maderista insurrectos. Archival records show that the Shelton-Payne Company had assets exceeding $1,100,000 dollars in 1913.
The U.S. Bureau of Investigations, forerunners of the FBI, allowed Mexican government spies to openly operate in El Paso. The spies were permitted to follow and search anyone who bought arms and ammunition at places such as the Shelton-Payne Arms Company. The Merrick Building, which housed the Shelton-Payne Arms Company was constructed in 1887.