The ledgers in this collection were donated to the museum over several years. Many belong to either the Superior Court of Ventura County or various offices and departments within the county's administration, as well as several private businesses or clubs. There are also a few still unidentified ledgers. The ledgers contain notes, financial accounts, or administrative records for a wide variety of agencies and businesses. Some ledgers may contain additional papers or correspondence.

This collection consists of glass plate negatives, mostly gelatin glass negatives, and some photographic prints. While most of the images in this collection were captured by either John C. Brewster or Waldo Henry Dingman Sr, some may be the work of other photographers. The negatives are largely of Ventura County locations, historic sites, persons, and events, such as parades and holiday celebrations. There are also several boxes of unidentified negatives.

This collection consists of glass plate negatives, mostly gelatin glass negatives, and some photographic prints. While most of the images in this collection were captured by either John C. Brewster or Waldo Henry Dingman Sr, some may be the work of other photographers. The negatives are largely of Ventura County locations, historic sites, persons, and events, such as parades and holiday celebrations. There are also several boxes of unidentified negatives.