Unique images of England's 'unseen' urban poor are unearthed in Tasmanian museum

A unique collection of 19th-century watercolours that offer a rare insight into England's urban poor has been found in a drawer in a back room at a Tasmanian museum.

The 51 paintings, which depict beggars, street sweepers and pedlars in the 1820s, represent a remarkable piece of social history, according to David Hansen, the senior art curator at the Tasmanian Museum and Art Gallery in Hobart.

The portraits are the work of a little-known English artist, John Dempsey, who travelled the country in search of subjects. Most are dated and record the places where they were executed as well as, in many cases, the names and occupations of the sitters.

While numerous pictures exist of aristocrats and land-owners from that era, the poor and working classes were almost never painted as individuals. "These are images of the previously unseen," said Mr Hansen. "They are a slice through a social class. They are quite extraordinary."

That view is shared by British art historians, including the noted Constable specialist, Michael Rosenthal. Mr Rosenthal examined the watercolours and said he had never seen anything like them. The National Portrait Gallery in London is considering exhibiting them.

It is not clear how the folio ended up in Tasmania. It was donated to the museum in 1956 by a man named C E Docker, but his background is unknown. Mr Hansen has contacted every Docker in Hobart, but has failed to glean any information about the mystery benefactor.

For decades, the portraits were wrongly attributed to another English painter of that time, George Scharf. They were not regarded as particularly interesting. The museum's curators forgot that they existed.

It was only when the print room was relocated that they came to light. Mr Hansen, who found them, said: "I thought 'what the hell are these?' I knew there was very little imagery of the English working classes from that late Regency/ early Victorian era. To find that quantity and that quality, with that wide geographical range, and with the names attached, was pretty amazing."

The handful of other portraits of the poor from that era are sentimental and sanitised. Dempsey's are raw and realistic. "They have a compelling verisimilitude and documentary fidelity," said Mr Hansen.

"They bring a whiff of the 1820s into the early 21st century." Dempsey travelled from Plymouth to Scotland, and from Liverpool to Great Yarmouth. He painted porters, bootmakers, town criers and veterans of the Napoleonic wars.He painted "lunatics", and people with missing limbs and deformities.In the most of art of that period, the working classes are either relegated to the background, or "made digestible to a middle-class audience", according to Mr Hansen.

"Dempsey's people are very unpalatable. They are hairy, ugly, spotty. They live a grim existence, in dire poverty." He said the watercolours were astonishingly detailed. "You see every carbuncle, every missing tooth, every stitch of ragged clothing. It is almost a scientific presentation. The subjects are like specimens, like butterflies on pins. Dempsey is an anthropologist of the underclass."

Of the artist himself, little is known. Mr Hansen calls him "a bare whisper in the literature of art history". An itinerant miniaturist, Dempsey later became a successful cutter of silhouette portraits. But his clumsy rendering of anatomy suggests he had no academic training.