The Jules Merron Collection, sold by David J. Holmes Autographs in Philadelphia, listed two copies of Mark Twain's Autobiography. Both were first editions, State A, and one was listed at $110 while the other was listed at $100. As with any book, condition is the primary factor. Also bear in mind that the presence of the dust jacket is desirable. The Merron copies had just jackets. American Book Prices Current, an annually produced guide, is a good way to determine what prices are being realized at the previous year's auctions. Auction prices realized generally are higher than prices realized through private and catalog sales. Enjoy the books. Marcus W. Koechig