4 pages, 8vo, small rust mark from paperclip at top of pages 1 and 4, otherwise fine, with original stamped and postmarked envelope in Darwin's hand." /> DARWIN, Charles. Autograph letter signed ("Ch. Darwin") to George Cupples (1822-1891), Beckenham, England, 20 September [1870]. <I>4 pages, 8vo, small rust mark from paperclip at top of pages 1 and 4, otherwise fine, with original stamped and postmarked envelope in Darwin's hand</I>. | Christie's