Her article in thepeeage is here.
From eBay. This is one of several prints of beauties in Queen Victoria's court released in 1849. The original was prepared a decade or so earlier based on her dress and coiffure.
Lady Louisa wears a dress with a natural waistline and pelisse bodice and a straight "Victorian" coiffure.
Keywords: Horsley-Beresford family, Brudenell-Bruce family, Marquise, British, straight coiffure, floral headdress, off shoulder scoop neckline, modesty piece, fan front bodice, waist band, natural waistline, full skirt, brooch, bracelets, wrap, handkerchief