Letter, from Adolphe Quetelet to Sir John Herschel, dated at Brussels Autograph letter signed by sender. Translation of John Frederick William Herschel's article Light begun. Publisher is in Paris. Gives name of collaborator as [P. F.] Verhulst. Has heard of others translating John Frederick William Herschel's work. As director of Brussels observatory, Adolphe Quetelet needs best works of astronomy. Would John Frederick William Herschel help? 24 January 1828