Series III. Correspondence is mainly the correspondence received by E. S. Coe. The folder marked “Letters regarding the Iron Ore Tract” includes letters from Albert B. Hill, Daniel A. Patch, and David Pingree to E. S. Coe. In the front of the folder is an index of the letters. Other correspondents include David Pingree, William Heywood, George P. Meserve, Mark Haskell, Charles H. Ladd, Joseph S. Hall, Amos B. Merrill, and Joseph W. Weeks. This series is organized chronologically.