In August of 1866, Mark Twain returned to California from his trip to the Sandwich Islands (Hawaii) which had begun in March of that year. He had contributed numerous travel letters about the islands to the Sacramento Daily Union. In October 1866 he delivered his first lecture on the Sandwich Islands in San Francisco and continued on throughout California on 16-engagement lecture tour which took him throughout California and Nevada. He contributed at least three letters of correspondence to the San Francisco Bulletin during this time frame which described the interior towns of California through which he traveled. These letters were reprinted in Mark Twain's Western Years, by Ivan Benson in 1938.
November 30, 1866 - Includes observations on Sacramento; Marysville; Grass Valley; The Eureka mine; Nevada, CA
December 6, 1866 - Includes: To Red Dog and Back; A Memento of Speculation (Meadow Lake); An Aristocratic Turn-Out; Silver Land (Nevada)
December 7, 1866 - Includes observations on San Jose; California silk production; Mark Twain Mystified by a telegraphic despatch