There are 47 distinct collections of the library, organized mostly by donor. The Conway Collection was one of the first donations to the library, containing over 5,000 volumes in Spanish and English, along with over 20,000 manuscripts dating from the 16th to 18th centuries. English language items include "The Americas" and the "Annual Reports of the Bureau of Ethnology" along with writings by Irishman Guillen de Lampart, who led a colorful life in Mexico ending with his execution there in 1659. Manuscripts date from the Conquest to the Porfirio Díaz era. The collection was also the source of the library's oldest book.