Landscape designer Humphry Repton’s 1810 “Red Book” for Armley House. The book is the subject of a new short film narrated by Jeremy Irons. (Oak Spring Garden Foundation)

Humphry Repton may not have been the greatest landscape designer in history, but he was surely one of the smoothest.

Working in England in the late-18th and early-19th centuries, Repton wrote letters to his clients that were fulsome to the point of fawning. When one patron complained that with fame he was neglecting her garden, he replied that he “felt a degree of pain, not from a consciousness of having deserved the rebuke, but from the reflection that this favorite object, like a Child outgrowing the protection of its parent, no longer requires the attentions which gave me so much pleasure during its infancy.”

The Garden Museum in London recently examined Repton’s legacy in a show marking the bicentennial of his death. The museum’s director, Christopher Woodward, likens Repton to Jane Austen’s obsequious curate in “Pride and Prejudice,” Mr. Collins, though with a great deal more perspicacity. “He was very adhesive to clients and would get the measure of a client very quickly,” Woodward says.

And unlike Mr. Collins, Repton would be entirely comfortable in our fast-paced world. “A very modern figure,” Woodward says. “Today, he would be checking his emails.”

Repton was famous for producing before-and-after scenes using flaps. The flap here is down and shows an existing entrance to Armley House. (Oak Spring Garden Foundation)

The flap is lifted to show his improvements. The cottage is gabled, thatched and trellised, and a driveway provides a new approach to the estate. (Oak Spring Garden Foundation)

By carriage or on horseback, Repton traveled a bone-rattling 5,000 miles a year across England’s rutted and hazardous highways. He is thought to have produced almost 400 major landscape designs over his life, not bad for a man who began his career in his mid-30s after a number of other incarnations, including flutist, artist and textile merchant.

As with Austen and her works, Repton captured his age in his art, but also transcended it. “Thackeray or Trollope feel very Victorian. Jane Austen feels very now,” says Woodward. “And Repton has the same quality.” In “Mansfield Park,” Austen even names Repton as the must-have space maker.

Celebrity can be fleeting. The secret to Repton’s longevity lies not with Austen, however, but with an ingenious “before and after” device that he cooked up. For each property, he would produce a hand-painted and hand-scripted “Red Book,” equipped with hinged overlays or flaps that allowed the viewer to see the existing landscape and, by lifting the “slides,” how it would look if the design were executed. The books — Repton may have gotten the idea from medical texts, which used flaps to reveal layers of human anatomy — are named for the color of their leather binding, though some are in less vibrant hues.

In the Red Books, the effect was — and remains — irresistible. The visuals are effective and the transformation immediate.

Through proposed modifications and additions, Repton showed in his watercolors how the scene could be dramatically changed to become more alluring and imposing, and with views that offered teasing glimpses of the grand house as you rode up in your carriage. Driveways were made more sinuous, pockets of woodland were removed or added, gatehouses built and ornamental ponds turned back to nature.

This view from a bridge shows Armley House on the ridge of the distant hill. Repton used the image to argue that the house was disconnected to the landscape. (Oak Spring Garden Foundation)

The flap is lifted to reveal an extensive ribbon of new woodland that does away, Repton wrote, with “that bleak surface of lawn which now seems to separate the house from the wood below.” (Oak Spring Garden Foundation)

Often Repton urged that a house of homely redbrick be replaced by one with dressed stone with Palladian touches. He returned formal terraces around the house that had been swept away in the previous century, paving the way, for better or worse, for Victorian parterres.

Now Repton’s Red Books have been brought to animated life in an eight-minute film, based on his 1810 design for Armley House, the property of industrialist Benjamin Gott on the outskirts of the northern city of Leeds. Gott’s house sat on a ridge between two quintessential features of the early industrial age, a hulking textile mill and a canal. The mill was Gott’s, and at the time was the largest gaslit factory in Europe.

The film, “A Generous Deceit,” was prepared for the exhibition Repton Revealed, at the Garden Museum, which marked the bicentennial of the designer’s death.

British actor (and gardener) Jeremy Irons narrates the film, rendering Repton’s flowery language coherent, not to mention melodious. His easy authority tempers Repton’s overwrought prose.

Instead of depicting before and after flaps, animator Tom Langton took high-resolution scans of the original watercolors and spent six weeks bringing them to life in subtle transformations. The film was produced by Third Channel and directed by Dorothea Gibbs, and the score was composed by Diego Carceres and Santiago Posada.

The Armley House volume was one of four Red Books in the collection of the late bibliophile Rachel “Bunny” Mellon of Upperville, Va., and was provided for the project by the nonprofit organization she founded, the Oak Spring Garden Foundation, which also financed the film.

Whether rooted in contemporary attitudes toward industry or Repton’s salesmanship, the mill is presented as a major element in the landscape, never mind that as a primitive factory, it would have been noisy and hazardous. The mill is, in Repton’s words and Irons’s voice, “an interesting object in daylight and at night presents a most splendid illumination of gaslight.” Meanwhile, the “misty vapor” of yonder Leeds dances like some sort of divine aurora borealis. Not bad for coal smoke.

Repton designed for old- ­moneyed aristocrats, but his work for Gott placed him firmly in the fold of forward-thinking entrepreneurs in late-Georgian England. Repton found willing patrons in the nouveau riche world of Napoleonic war profiteers and industrialists such as Gott.

Repton’s business model was based on selling his designs, not necessarily executing them. Other prominent landscape gardeners made the bulk of their money in the actual construction of the gardens.

There was less money in Repton’s approach, but it allowed him to build a prolific body of work. He would come to a property for a few days, and a couple of months later, the patron would receive the Red Book, paying handsomely for the visit and the book.

Approximately 180 Red Books survive. They are highly collectible and, depending on their significance, sell in the art world for $50,000 to $250,000, Woodward says.

The books themselves embody the essential dynamic movement of Repton’s landscapes. In the 18th century, English landscape gardens counted on establishing fixed scenes to be framed — the distant temple reflected before a lake, for example.

By contrast, Woodward says, Repton saw a succession of interrelated scenes unfolding at almost 20 mph, the pace of a carriage. Repton had shifted presciently from stills to video, or even CGI.

The rare book library at Dumbarton Oaks in Georgetown owns two Red Books, one of Glamham Hall in Suffolk and one of Brandsbury, an estate in what is now west London. The first dates to 1791, the second to 1789. At the time, it was fashionable for the image-minded classes depicted by Austen to travel the country to view grand houses. In the Brandsbury Red Book, you see three well-dressed voyeurs — two young ladies and a gentleman — trying to see beyond a tall stockade fence at the perimeter. In the improved scene, the fence is gone to reveal a field marked by three specimen trees and beneath, an idyll decorated with six lounging longhorn cattle.

Dumbarton’s rare book librarian, Anatole Tchikine, said the only other volume with flaps that he is aware of dates to 1612, by Lino Moroni and artist Jacopo Ligozzi, and depicts St. Francis of Assisi in his hillside retreat. There is no reason to think Repton knew about this book. “He could have genuinely thought he was inventing the technique,” Tchikine says.

Repton is often compared to Lancelot “Capability” Brown, the greatest practitioner of the English landscape school and who did, indeed, get down and dirty in the construction of his grand schemes.

“Repton’s abilities as a designer aren’t really as strong as Brown’s,” Tchikine says, “but at the same time his way of packaging and presenting them to patrons is really successful.”

Irons, as Repton, sums it up best: “Others prefer still life. I delight in movement.”

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