Letter, from Augustus De Morgan to Sir John Herschel, dated at 7 Camden St. Autograph letter signed by sender. The tract John Frederick William Herschel means is by L. A. Sedillot on the history of astronomy of the Arabs. Comments on this. Possesses it but it is bound in with a lot of other papers so is too heavy to send. Would he give John Williams permission to open letters addressed to the President of the Royal Astronomical Society 13 November 1848