Cotman (1782-1842) came to London from his native Norwich in 1798 and soon entered the circle of artists centred around Dr Thomas Monro (1759-1833), a physician who welcomed watercolourists into his home, providing a meeting place, and offering financial support and the opportunity to study and copy his impressive collection. J.M.W. Turner (1775-1851) and Thomas Girtin (1775-1802) were among his many protégés. Cotman travelled widely around Britain, producing many pencil drawings and colour sketches that he later worked up into carefully patterned watercolours. Trips to Wales in 1800, and to Yorkshire in 1803 and 1805 were particularly fruitful. This watercolour is dated (as much by tradition as by any specific evidence) to just after Cotman's stay in northern Yorkshire, near Duncombe Park, in the summer of 1805.
The drop-gate (a light fencing slung from a beam, to prevent cattle from straying along the course of the river), is rendered in drab, earthy colours typical of Cotman's work of this time. The depth of the scene is flattened into a delicate pattern, playing subtly between the picture plane and receding space. Foreground and background details are simplified, and brought together by zig-zag lines across the sheet, a masterpiece of refined restraint and sensitive design.