Original electrical trade vintage catalog for SPEER CARBON COMPANY, was located at Lincoln Avenue, St. Marys, PA. Manufacturers of motor and generator brushes, carbon arc welding electrodes, graphite anodes and carbon products. There's one right brush grade for every motor and Speer makes it. Charts showing Alternating Current slip rings and commutators, Direct Current voltage below 80 and 80 to 750 and characteristics of grades are provided. Disbound from a large 1944 electrical construction materials book, this unique old one page technical brochure would display wonderfully matted and framed. A marvelous addition to your retro electric equipment library.