The Percival Hall Papers consist of letters, clippings, certificates, diaries, newsletters, telegrams, poems, photographs, by-laws, thesis, sermons, and lectures. The collection, which consists of approximately 4,250 pages, dates from 1887 to 1958. The bulk of the collection consists of his lectures, speeches, and sermons. The next bulk of the collection consists of his biographical information. The bulk dates are mostly between the 1930s and 1940s. The largest subject in the collection is focused on the education of the deaf. Percival wrote many articles and speeches on deaf education. There are letters and greeting cards included in honor of President Hall’s anniversary of his employment and birthday celebration. One interesting item in the collection is an 1890 thesis that Percival wrote while he was a student at Harvard. The thesis is titled “Harmonoids.” It is about mathematics. Also included in the collection is a correspondence between Percival and the Como Orchard Land Company in the West, where he invested in stocks with the company.