Copy letter, from Sir John Herschel to Commander of Steam-Packet Talbot, dated at Slough Copy of a letter. John Frederick William Herschel gave passport to commander or steward with instructions to use it to retrieve mail forwarded to John Frederick William Herschel in Calais. Lack of response concerns John Frederick William Herschel. Please procure mail and send it with John Frederick William Herschel's passport to 9 Downing St. Reward. 4? September 1822