The index is organized alphabetically, not chronologically. The following have not been indexed: fictional characters, newspaper articles and subheadings, all subjects of all letters, whether paraphrased, summarized, or quoted.
Items within the Addenda & Errata for Vol. I. are included in this index. This index includes books, and literary works, as well as the authors of those works (these were not indexed for Vol. I). Readers may seek up to date bibliographies for Samuel Clemens’ vast array of writings, including the on-line site of Camfield’s Oxford Companion to Mark Twain. Also, Thomas Tenney’s Mark Twain, A Reference Guide (with many supplements) is still a central reference for works written about Clemens. Alan Gribben’s Mark Twain’s Library: A Reconstruction is an excellent source for Sam’s literary interests and ownership of a vast library of works.
This index focuses on persons and places, with lesser emphasis on events and subjects, such as baseball or International Copyright efforts. Those who corresponded with Sam are indexed; locations are limited to those Sam stayed or planned to visit. Whenever possible, surname, first name and middle initial or middle name are listed. In some cases these are unknown; some individuals may be double listed, when it was undetermined if they were different people, such as a “Mrs.” listing and a maiden name. If Sam referred to someone in a letter and only the last name is given, and no other reference was found, then the last name only is indexed. Merchants and commercial firms, when named as “John B. Smith, Plumber,” are alphabetized and indexed in the same order as the literal company name, in this case under “John” not “Smith.” Likewise, “Wm. H. Jackson & Co.” as “Wm” not as “William” or “Jackson.”
Mark Twain’s major literary works, may be found directly by name of the work. His minor works, as well as a sprinkling of his interesting events, opinions and experiences may be found as subheadings under Clemens, Samuel L.: Sub headings are indented and underlined; sub-sub headings are doubly indented, etc.. The principal subheadings for Clemens are: