Madrid, August 20, 1843. 12mo. 4pp. Written by Irving while serving as U.S. Minister to Spain (1842-46) to an unnamed recipient, regarding the return of his secretary, Alexander Hamilton Jr. (grandson of Founding Father Alexander Hamilton). Irving expresses concern about Hamilton's health and urges caution about an early return to Madrid: "I again wrote to him some time afterward, mainly to reiterate my caution about his setting out on his return too soon: and I now beg you to urge the same council upon him in my name". Irving goes on to write about his improving health: "My own health is improved; I have got through the heat of summer without inconvenience..." Creasing from original folds, signature clear and strong.