From Wikipedia.
Natalia Galatzina wears a wide brimmed hat decorated with roses and a dress with an off shoulder bateau neckline above a flaring bodice as Vesuvio smokes behind her. Her skirt is decorated with two rows of rosettes and two rows of patterned material.
Keywords: 1822, Brullov, Natalia Galitzina, Apraxin family, Galitzine family, Russian, Countess, hurluberlu coiffure, floral hat, lappets, scarf, off shoulder bateau neckline, epaulettes, long full sleeves, cuffs, waist band, natural high waistline, A-line skirt, rosettes, parasol, wrap