This collection includes photographs, photo albums, negatives, and blueprints pertaining to the operations of Wendall P. Hammon, and his various companies, including Yuba Construction Company and Yuba Consolidated Industries. Photographs, albums, negatives, and blueprints relate to the dredging, manufacturing, and mining activities of the Hammon enterprises. The blueprints contain specifications for various dredger sizes and types of dredgers, including 3, 3 ½, 4 5, 6, 10, 11, and 12 cu. ft., as well as gold, tin, and close connection dredgers. The photographs and albums feature various dredger operations, manufacture, parts, and equipment. Some photographs depict foreign dredger and mining operations. Dredgers were operated in many locations both domestic and abroad. Domestic locations include Northern California, Alaska, Colorado, Utah, Wyoming, and Florida. The locations of foreign operations included the Philippines, Bolivia, China, Russia, Germany, Dutch Guiana, Guatemala, Malaysia, Brazil, and South Korea.

The various blueprints relate to the following companies: Boston & Oroville Mining Company, Boston and California Dredging Company, Yuba Construction Company, Yuba Consolidated Industries, Asnazu Gold Dredging Company, Lancha Plana Gold Dredging Company, Natomas Consolidated, Oroville Gold Dredging Company, Panob Gold Dredging Company, Yreka Gold Dredging Company, Yuba Consolidated Gold Fields, Supia Gold Dredging Company, Thurman Gold Dredging Company, Boston Machine Shop, Tuolumne Gold Dredge Company, Bucyrus-Erie Company, South Patte Dredging Company, Snelling Gold Dredging Company, American Manganese Steel Company Comanche Gold Dredging Company, Bulolo Gold Dredging Company, Gold Hill Dredging Company, Colorado-Pacific Dredging Company, Pato Consolidated Gold Dredging, Ltd., Mitsui Company, La Grange Gold Dredging Company, Yukon Pacific Gold Mining Company, Yuba Associated Engineers, Ltd., and the Yukon Gold Company.

Blueprint manufactures include, Walter W. Johnson Company, H. G. Peake Engineering Company, Lancaster Iron Works, Placer Management Limited, Placer Development Limited, Joshua Hendy Iron Works, Columbia Steel Casting Company, Union Iron Works Company, Bethlehem Shipbuilding Corporations, Ltd., and Taylor-Wharton Iron Steel Company