A library devoted to the writing of John Ruskin opens next Saturday. Nonie Niesewand looks at the legacy of the great art critic and social commentator
It's petty, I know, which isn't at all Ruskinian in spirit, but there is something satisfying about discovering that John Ruskin, the most opinionated 19th-century writer on art, architecture and design, couldn't design a boat that floated or a coach with enough storage space for his library. He kept his books in a bathtub lashed on top of the carriage, which his coachmakers in Camberwell built to his specifications, complete with secret compartments. And his broad-beamed cross between a kayak and a currach, Jumping Jenny, unlike its designer, wasn't known as a mover and shaker on Lake Coniston.

Ruskin, whose centenary in two years will be marked by an exhibition at the Tate Gallery, had volumes to say on almost every subject of the man-made world. For him, design and art were connected to morals, religion and the state of society as a whole, and his anger at exploitative capitalists and their lack of compassion for the poor made him an international hero. His book Unto this Last was translated by Mahatma Gandhi into Gujarati, Clement Atlee claimed to be influenced by him, and Kenneth Clark thought his views to be "the truisms of the Welfare State". The National Trust was another Ruskin-inspired idea.

Tolstoy said of him: "Ruskin was one of those rare men who think with their hearts, and so he thought and said not only what he himself had seen and felt, but what everyone will think and say in the future." With this kind of hype, you need to go back to the master and check out the relevance of Ruskin today.

Two memorials administered by the Ruskin Trust that are open to the public give us a better understanding of his vision: his old home, Brantwood, in the Lake District at Lake Coniston, and the new Ruskin Library at the University of Lancaster, some 40 miles farther down the M6, which opens next Saturday. This beautiful shrine to house Ruskin's writing catapults his thoughts into the electronic age, with all 39 volumes of his library housed on a single CD-Rom. Professor Michael Wheeler, director of the Ruskin programme at the university, uses it all the time as he writes his book on Ruskin.

"The great prose writer of the 19th century does have his nervous tics, you know," Wheeler points out. "He uses the expression `perpetual paradise' nine times in Volume 27 of his library to describe northern France. And, for once, Ruskin wasn't being ironic."

His old home, Brantwood, is eccentric and unpretentious. Architecturally it is slightly strange, as it grew from a simple whitewashed farmhouse to encompass outbuildings, boathouses, turrets with lattice windows and bolt-on mullioned stone windows with an arched double entrance. Comfortably contoured into the steep slope above Lake Coniston, it was more of a laboratory for Ruskin's ideas than a place to pass the style trial. So Brantwood comes with a disclaimer that, while Ruskin had strong ideas on the glories of architecture and ornamentation, he referred mainly to places designed for rest and contemplation, not to his own home, which was a workplace. Having bought Brantwood in 1871 for the view of the lake, Ruskin perversely turned his back on it, setting a garden seat made of granite tombstones halfway up the hill, from which one could to contemplate a waterfall trickling down the hillside.

The Ruskin Trust director, Howard Hull, who came from the Royal College of Art, where he was design director, has pieced together a fascinating glimpse of Ruskin's rather reclusive life from 1872 until his death at Brantwood in 1900, using substantial quotations from his literature, photographs and watercolours. The house was in disrepair after being left to his cousin, Joan Severn, but the trust managed to recreate the interiors for eight rooms from old photographs. The bottom of the lake was dredged for a lot of china and glass, while village auctions unearthed some of the furniture. The spirit of Merrie Olde England has been kick-started by a band of potters and gardeners and the "Jumping Jenny" wholefood cafe. Even the Ruskin lace makers - a project started by Ruskin himself - have begun working there every Thursday, selling their efforts in the bookshop.

Making Ruskin more accessible means that boatloads of tourists can gossip over Ruskin's portrait painted by Millais, who ran off with Ruskin's wife Effie. Unflinchingly, visitors point out that he went mad, as they look for the collection of cut-throat razors and neck collars in his bedroom. There, you can see his deathbed and read the words he wrote so forlornly, describing that "most provoking and disagreeable of the spectres developed out of firelight on my mahogany bedpost".

He knocked his study and drawing room into one room and furnished it with a window seat, mahogany furniture and a vastly over-scaled Luca della Robbia's Madonna and Child as the fireplace overmantel holding his collection of Cyprus pottery. Twee floral bouquets in blue stamped all over the wallpaper are Ruskin's own design, taken from an embroidered detail pictured in Marco Marziale's painting The Circumcision of Christ, which he had seen in the National Gallery. When it came to his own work he wasn't so exacting. "It might look like a harlequin's jacket for all I care," he said.

After all this applied arts and amateur decoration, it is imperative to make the pilgrimage to the Ruskin Library at Lancaster University. The library, designed by MacCormac, Jamieson and Pritchard, which opens on Saturday, houses Ruskin's diaries, 8,000 letters, 3,500 books and more of his published writings, as well as photographs and daguerrotypes. There are exhibition rooms upstairs that currently show Ruskin in the clouds - appropriate for a man who predicted global warming and the atom bomb. "Blanched sun - blighted grass - blinded man," he wrote for a lecture he gave in 1884 called "The Storm Cloud of the Nineteenth Century".

On an escarpment overlooking the sea, the building is shaped like the two burning bows of William Blake's Jerusalem. Ruskin, who railed against the Satanic mills and reproved Bradford wool merchants for their bourgeois tastes and values, would love the spirit in which the architect, Richard MacCormac, approached the building. It has all the drop-dead glamour that rich colours and silky smooth plaster bring, which is all the more startling when you consider that a great deal of the building is precast concrete. Outside, white concrete blocks with a sparkly marble aggregate, and green, polished precast concrete bands, recall Ruskin's fascination with Venetian and Tuscan materials, but interpret them for the post-industrial age.

MacCormac describes the building as "Byzantine in colour, Gothic in mood, a metaphor for Ruskin's Venice." Also Ruskinian in spirit is the way in which the stainless steel plates or bosses bolted on the outside declare how the building is made. One imagines St Marks in Venice to be a pure marble building, yet it was built in brick with thin layers of marble riveted on. Of course, it was Ruskin who taught us to see it that way: nothing is purely for decoration, and a building, in Ruskin's words "confesses the way it's made".

Bronze doors in the front of the library are guarded by shutters like a medieval altar triptych. The daguerrotype of the north-west portal of St Marks housed in the archives inspired an etched glass panel by Alex Beleshchenko. Through bronze doors, the clear glass and slate floor are like the Venetian lagoon, from which the Venetian red rectangular box of the archive rises up. The red box is full of Ruskin archive material except for the top half, which resolves into a glorious red meeting room. In a dazzling contrast, oak beams and panels are sometimes roughly adzed, sometimes silkily smooth. You can walk right round this reliquary of a box, coming between it and the black cement walls, which are honed into craggy points like the face of the Eiger. There are more contrasts: rich versus workmanlike materials, smooth versus rough, industrial cement versus handcrafted wood and plaster, all handled with integrity, give the Ruskin library a positive dynamism. From this hothouse, many ideas will flow and you can expect a lot more writing on Ruskin.