Correspondence, class notes, lecture notes, drafts of his book, Ancient Israel, autobiography, diaries, journals from a mission for the Church of Jesus Christ of Latter-day Saints (LDS) to northern states. Much of the later material in the collection consists of Snell's defense of his book against Mormon conservatives and of his attempts to avoid excommunication proceedings for his holding the belief that Blacks should be allowed to hold priesthood in the LDS Church. Also includes writings of John W. Fitzgerald concerning this topic.
The bulk of the collection is letterbooks (1880-1901), dealing primarily (after 1883) with the affairs of the Thatcher Brothers Banking Company; also includes materials concerning the L.D.S. Church in Cache Valley, the Logan L.D.S. Temple, the Utah and Northern Railroad, Logan City Government, and the Democratic Party. Personal materials include correspondence with plural wife, Fanny, and son, George, and provide information on the inner workings of the institution of plural marriage. The miscellaneous papers are largely of a financial nature, and include papers of Noble Warrum, R.W. Sloan, Edward E.H. Holden, and several mining companies. Also includes class notes and missionary journal of George W. Thatcher Jr. promoting the Young Men's Mutual Improvement Association (YMMIA) in southern Utah and commonplace book of Jean C. Thatcher.