Subseries B. Legal and Business Papers document the close relationship between Duncan's legal work as a probate lawyer and Justice of the Peace and his real estate investments in eastern Massachusetts and New Hampshire. The correspondence contains information on Duncan's management of various real estate transactions, as well as material concerning the Boston and Maine railroad. The real estate transactions are largely deeds and agreements in which Duncan conducted business for himself or on behalf of clients. The papers of the Haverhill Bridge document the activities of the proprietors of the bridge and associated land transactions and disputes. The railroad corporation materials contain notes on the status of a number of railroads, including the Haverhill and Andover, Eastern, Western, and the Andover and Wilmington lines. The Eliphalet Webster account papers are financial statements for a store owned by Duncan and managed by Webster.