Letter, from Robert Walker to Sir John Herschel, dated at Harley, near Bath Autograph letter signed by sender. Miniature of William Herschel's portrait was lost and recovered. At same sale where Robert Walker bought William Herschel's portrait, was sold 7-foot reflector, inside which were several papers in William Herschel's handwriting. New owner would not accept £40. Does John Frederick William Herschel advise offering more? 14 January 1860