The collection comprises papers illustrating how automobile businesses were run and managed during the early stages of development of a motor car. It predominantly relates to Bohringer’s involvement with The Princeps Motors & Engineering Co., where he served as company manager during the early 1920s. The collection contains general company papers, legal, share and patents documents, correspondence, certificates, tax returns, receipts and employment agreements, as well as manuscript specifications and drawings relating to the design of car parts.