This collection includes photographs, photo albums, negatives, and blueprints pertaining to the operations of Wendall P. Hammon, Yuba Construction Company and Yuba Consolidated Gold Fields. Photographs, albums, negatives and blueprints relate to the dredging, manufacturing, and mining activities of the Hammon enterprises.

The collection consists of a report from H.R. Edwards, Chief Engineer of Hammon Engineering Company to W.P. Hammon, managing director of the Yuba Consolidated Gold Fields. Included in the report are sections on railroad possibilities and an irrigation scheme. Appendices include a history and appraisal of the debris situation, a geologist's report, a report on hydraulic development, and a copy of the Caminetti Act.