Letter, from Edward Sabine to Sir John Herschel, dated at 3 St. James's Place Autograph letter signed by sender. Encloses letters from Heinrich Boguslawski and others about magnetic observatories at various foreign locations, e.g., St. Helena, Toronto, and Hammerfest, Norway. Is going to Glasgow for the B.A.A.S. meeting. Mentions s 8 September 1840