Ever since his death two hundred years ago Paul Sandby (1731-1809) has been damned with faint praise as “the father of English watercolour painting”. Sandby was born into the age of Hogarth, prospered during the era of Joshua Reynolds – playing an active part as one of the founders of the fledgling Royal Academy – and contributed to the founding of a native school of British landscape painting. But it has been his fate to be remembered as a forerunner, a journeyman whose dutifully literal records of the natural scene were destined to be overtaken and transformed by the more poetic and imaginative pioneers of the Romantic movement – Thomas Girtin, John Constable and above all J.M.W. Turner. Henry Fuseli, who was the Royal Academy’s Professor of Painting at the turn of the nineteenth century, gave a lecture on “Invention” which included an unambiguous dig at everything that Sandby stood for. Fuseli attacked what he saw as the prevailing spirit of conservatism in English landscape art, commenting that most landscapes were merely pedestrian works of record, no more than a “tame delineation of a given spot; an enumeration of hill and dale, clumps of trees, shrubs, water, water, meadows, cottages and houses” – mere “topography”, in other words, “a kind of map-work.”

Sandby was dead by the time Fuseli’s words were published, but he was certainly the principal target of the attack. He had founded his career on topographical accuracy, priding himself precisely on the absence of that very quality of transfiguring imagination that the Romantics berated him for lacking. He had in fact trained in “map-work”, learning his trade as a military draughtsman in Scotland in the immediate aftermath of the failed Jacobite rebellion of 1745. His earliest works include a number of chillingly dispassionate records of the landscape around Culloden, drawn to give the English army a tactical mastery of the terrain should hostilities resume. His cool, phlegmatic style would subsequently find favour with that pioneer of scientific exploration and survey, Sir Joseph Banks. As the diarist Joseph Farington noted, with a slight air of disapproval, “Accuracy of representation seems to be a principal recommendation to Sir Joseph.”

It is, inevitably, on Sandby’s work as a topographical artist that the Royal Academy’s exhibition focusses. He is perhaps best known for the many views of Windsor Castle and its environs that he created for the monarchy during the 1760s, but his most interesting work tends to be rather edgier and less officially cleaned up. During his many extensive tours through England, Wales and Scotland, Sandby recorded a nation in the first throes of huge social change. At first sight, many of his pictures might seem merely mundane, but they are full of subtle, thoughtful observations. He noted shifts in the patterns of land use, he drew the unemployed and the indigent and he observed the inexorable growth of new towns and new industries. He was seemingly drawn to scenes that exposed ambiguities and even outright fissures in society: he studied the fascinating throng of a race day crowd at Ascot (more than a hundred years before Frith painted Derby Day), and he drew the ragtag encampment of soldiers called to suppress the anti-Catholic mob that had run amok during the Gordon Riots. In London, where he had settled early in his career, he drew and painted migrant workers (with whom, as a travelling and jobbing artist, he perhaps felt some fellow feeling) with a compelling and vibrant alertness to detail and character. A hissing cat arches its back at a bawling laundrywoman; a fish vendor somehow balances three baskets filled with flounders on different parts of his anatomy; an out-of-work naval conscript turns his hand to selling stockings, as corpses dangle on a gallows and an unfortunate miscreant wriggles in the stocks behind him. This is the world of Fielding and Defoe, rendered in pen and ink, watercolour and pencil.

Sandby was particularly interested in the places where town met country, depicting them with the wry and slightly melancholy awareness that village by village the outskirts of London were gradually being devoured by the unstoppable surge of development. Morning, View on the Road near the Bayswater Turnpike recalls a time when Bayswater was still “Bayswatering”, a place where weary drovers watered their horses before going on  into London. A group of builders mix mortar while a detachment of soldiers enjoy a beer or two at the Swan Inn. In the far distance, a line of washerwomen carrying bundles on their heads make their way towards the Westbourne stream, in Westbourne Grove. They are nymphs resembling ancient caryatids, hovering at the edge of a world about to vanish. Sandby’s sense of being witness to a disappearing landscape is movingly apparent in several of his later watercolourss, where he seems to become fixated on the majesty of great spreading oak and beech trees. He draws them in tender, loving detail, having them loom over the landscapes they occupy like monuments formed by nature. They are symbols of a peaceful, pastoral Britain that the artist longed to preserve but knew was under threat. Despite his reputation as a “tame delineator” Paul Sandby was perfectly capable of being stirred by strong and deep feeling.