The collection consists primarily of papers related to critical work by Harper (Princeton Class of 1884) on the English poet William Wordsworth: the holograph manuscript of Harper's William Wordsworth: His Life, Works, and Influence (New York: Charles Scribner's Sons, 1916), with reviews of the book; letters and documents concerning his book Wordsworth's French Daughter (1921); letters to Harper by Emile Legouis, the French Wordsworth scholar, and by Gordon Wordsworth, grandson of the poet; and offprints of articles about Wordsworth. In addition, there are manuscripts for some of Harper's poems, stories, articles, and speeches; many letters (1907-1935) to his sister, Mary Harper McCreary, from England and France, including many written during World War I; and letters by Woodrow Wilson, a long-time friend and colleague, Booth Tarkington, and Thomas Hardy. Also included is a poem about Sacco and Vanzetti.