Her article in thepeerage is here.
From bbc.co.
Lady Acland's hair is set higher in the center with small poufs on the sides, a style that would persist and be elaborated on for over another decade. Her dress has a sweetheart neckline.
Keywords: 1814, Lawrence, Lydia Elizabeth Hoare, Lady Acland, Hoare family, Acland family, British, curly coiffure, sweetheart neckline, modesty piece, quarter length under-sleeves, quarter length over-sleeves, waist band, close skirt, floral bodice ornament, bracelets, wrap, lace