Rather than a ‘road over mountains’ as Finberg described it,1 this sketch, as Turner’s inscription tells us, is of the ‘W[ater] of Milk’, a tributary of the River Annan. Turner passed along the river on his journey from Lockerbie to Langholm. This sketch shows either the river, or the road Turner took winding between hills. There seems to be the roof of a farm building at the right. There is another sketch of the Water of Milk on folio 42 verso (D25606).
Finberg 1909, II, p.849.