An Eastern Pennsylvania Dunker named Abraham Harley Cassel (1820-1908). Although he enjoyed only six weeks of formal schooling, he began collecting as a youth and eventually owned one of the great personal collections of late 19th century America, at least 50,000 volumes. He stored these in his farmhouse near Harleysville, PA.
Cassel hoped that one of the newly emerging Brethren schools would secure his library intact for posterity. This was not to happen, but the major portions of his library did find safe havens in several repositories. A large fraction of his library was purchased for the new Mt. Morris College, IL, in 1881. A small but excellent selection went to the Pennsylvania Historical Society in Philadelphia, featuring rare Pennsylvania-German imprints. (Some of which can be viewed online at the Historical Society of Pennsylvania Digital Library). Finally, some 12,000 books, 4,000 pamphlets, and many manuscripts were purchased by M.G. Brumbaugh and donated to Juniata College in 1899. When Mt. Morris College folded in 1932, the Cassel Collection went to Bethany Biblical Seminary in Chicago. In turn, in 1994 when Bethany moved to Richmond, IN, its entire collection of Cassel books went with it. All the early German and German-American imprints before 1830 that had been classified and cataloged on OCLC were housed in the library of Earlham College; the remained were put into storage. Several years later, the latter portion of Bethany's Cassel collection, which consisted chiefly of 19th-century imprints, were donated to Juniata College.
Thus, Juniata currently holds perhaps two-thirds of the original Cassel Collection. Although the objects in the Cassel Collection date from the late 15th century and range over all fields of knowledge, the core of the collection is the large number of Pennsylvania-German imprints, that is to say, books published in North America in the German language. Included in the donation were scores of manuscripts from early Brethren history, including many letters written by Alexander Mack, Jr. The collected correspondence of A. H. Cassel, itself, is a valuable research source.