The original collection consists of letters received and drafts of letters sent, chiefly concerning Street's work as Indian agent. There are also a few papers of his sons, William B. and Joseph D. H., including two addressed to the latter in 1839 while attending the session of the territorial legislature, written by Judge Charles Dunn. Additional materials acquired later by the Archives include letters from Street's government supervisors and from others interested in Indian affairs including missionary Cutting Marsh, financial accounts, and receipts.
About two-fifths of the papers are original documents; the remainders are transcripts from the State Historical Department of Iowa.
