Letters, 1790-1823, to Henrietta Antonia, countess of Powis, mainly from her daughter, Lady Henrietta Antonia Williams Wynn of Wynnstay, co. Denbigh, written while accompanying her husband, Sir Watkin Williams Wynn, 5th bart, on a tour of Belgium, Switzerland, Italy and France, 1822-1823 (ff. 7-46v), and including a letter, 1790, from James Clark, Naples, enclosing instructions in Italian for making varnish for guazzo painting (ff. 47-50v).