This collection consists primarily of letters addressed to the West Philadelphia Base Ball Club during the season of 1867 with a few letters from 1866. Many items are challenge letters or letters otherwise scheduling matches. There is also a 6-page letter from the Excelsior Base Ball Club of Milford, Delaware, inquiring about a player named Fisher, who pitched for the West Philadelphia Base Ball Club and another team during the 1867 season. Most of the correspondents are from the Philadelphia area and include letters from the Olympic Base Ball Club, the Keystone Base Ball Club, and the Quaker City Base Ball Club. There are also letters from the Atlantics of Brooklyn and the New York Mutuals. In addition to letters from other Base Ball Clubs, the collection includes a small number of other correspondence, including a letter from the Ladies of the Seamen’s Relief Association (Philadelphia) requesting support for a fundraiser. Included among the letters is also a draft of the West Philadelphia Base Ball Club's letter of application to the National Association of Base Ball Players, the game's first governing body. Materials include letters and a telegram.