Mrs Fortescue was Towne's pupil Ann Sanders, daughter of Exeter merchant Thomas Sanders (d.1763), who married John Inglett Fortescue (1758-1840) of Dawlish and later of Buckland House, Buckland Filleigh, Lieutenant Colonel of the North Devon Yeomanry and MP for Callington in Cornwall from 1801 to 1803.[fn]Edge 2003; Devon Record Office 3106M/F/2[/fn] In 1778 Ann Sanders had copied Towne's drawing of Pines, made the same year (FT859, the original is FT143). Like the Acland commissions, the Fortescue watercolours appear to have been ordered not long after Ann Sanders's marriage at All Saint's Southampton on 22 September 1784, which produced one son born on 3 August 1785; a post-nuptial settlement is dated 1785.[fn]Edge 2003; Devon Record Office 3106M/F/2.[/fn] Ann Sanders was sister of Towne's patron Michael Dicker Sanders (see notes at FT392 and FT421).

Only two of the Fortescue watercolours have survived (FT425 and FT430), both of which were sold in 1972 by Mrs J Leahy at Sotheby's. Towne recorded Mrs Fortescue's purchase of only four Roman drawings (FT185, FT194, FT197, FT199), but one of the commissioned watercolours is numbered six (FT430). Of the two surviving watercolours, this one is dated 1785 and the other 1786. According to Towne's inscriptions, the drawings were delivered to Mrs Fortescue at Buckland House in 1786 (FT194, FT197, FT199); one inscription gives a date of 20 January 1786 (FT194).