Draft letter, from Sir John Herschel to Francis Lunn, dated at 2 Orchard St. Draft letter. Charles Babbage communicated [Edward] Smedley's note requesting John Frederick William Herschel to write an article on 'Heat' and an Introduction to Physical Science. Appears to be some misunderstanding as John Frederick William Herschel does not wish to write on Heat, no interest in the subject, but is prepared to write on Physical Optics. When will the latter article be required? 11 November 1824