Architecture: The things you've read are wrong: Everyone has attacked the new British Library, but Peter Dormer argues that it will be an outstanding building

COLIN St John Wilson - Professor Sandy Wilson as he is better known - is creating one of the finest public buildings in Britain: the new British Library at St Pancras, London. Yet he and it have so far received only the most dismal publicity. Bad news, such as an automated shelving system that at first threw books to the ground, encouraged critics to cry 'Scandal'. And ever since, they have dug the knife in deep: the library is too small, too expensive and far too late.

It is true that the building was first mooted as long ago as 1962, is not due for completion until 1996 and will have cost the taxpayer an impressive pounds 450m. And its reputation was hardly helped by a thoughtless attack by the Prince of Wales five years ago. In his television programme, A Vision of Britain, the Prince likened the library's design to that of 'an academy for secret police'. Like a pub bore, the Prince gave his opinion freely, but in ignorance: he has yet to tour the building, although he laid the foundation stone in 1982. When he does visit it, I hope he feels able to eat his words, and humbly and publicly apologise. .

In fact, Professor Wilson, his architect wife, Mary Jane Long, and their team are creating a building - certainly on the inside - of beauty, civility, finesse and usefulness. Yet, like other architects whose work was savaged by the Prince in the late Eighties, Professor Wilson has seen his career blighted: he has had no new work since those royal remarks.

Final judgement on the exterior of the library must await completion. At present, the 13-acre site is fenced by huge hoardings topped with razor wire, and one's view of the buildings is cut off at their waist. However, it is clear that Professor Wilson has avoided the dull, bureaucratic solution of creating a monolithic box. The buildings are not lumped together, but are stepped back and terraced. And the layout makes lively use of the asymmetrical shape created by the streets that bound the site.

The salmon-pink bricks and terracotta of the library walls, and the grey, beige and red paving and stonework of the courtyard will complement the colour and fabric of St Pancras Station Hotel (1868-76). This Neo-Gothic masterpiece, designed by Sir George Gilbert Scott, is itself being cleaned and repaired. When its wrappings come down, St Pancras will look as fresh as the British Library and, dressed in similar materials, they will weather together in harmony.

The courtyard that penetrates the mass of the library will relieve the sense of urban claustrophobia that afflicts this gulley-like stretch of Euston Road. Professor Wilson hopes that visitors, escaping from the carbon- monoxide rigours of the street, will be calmed by entering beneath the library arch through bronze gates - made to a design by the English lettering designer, David Kindersley - and walking across the court.

They will catch their breath when they enter the library, because the Great Hall that serves as the entrance is like a secular cathedral. You enter under a canopy so low that it is like passing through a medieval wicket gate; this is a foil to the sensationally wide space that then confronts you, arched over by a ceiling climbing rapidly up and away in two great wave- like curves to a height of five storeys.

One of the walls has been left as untreated red brick, and its colour and texture provide a strong but not overbearing contrast to the fine white plaster expanses of the other walls and the ceiling. Every surface is washed with daylight and each salient form is modelled with rich shadow.

The British Library is one of the world's most important centres for intellectual curiosity and achievement, and the Great Hall matches its purpose in providing an atmosphere of great dignity and liveliness. It offers no pomposity, no sentimentality and, above all, no crippling English nostalgia.

The anatomy of the architecture has been shaped very much by unfashionable function. This is a large building, housing 12 million books, general and specialist reading rooms, exhibition galleries, conservation and photographic laboratories, offices, lecture theatres, seminar rooms, a shop and restaurants. It may be a secular cathedral, but its medieval counterparts are but simple sheds compared with the complexities of a modern building such as this which is as much a mechanical and electronic machine as it is a work of art.

It has elaborate fire precautions, up-to-the-minute conservation techniques and complex machinery for delivering books around the building. It is also to be a major centre for the capture, storage and transmission of electronic documents.

Beneath the library are four great basements, each the depth of an eight- storey building. Together they house 186 miles of shelving. Above ground, in the western side of the building, there are the Humanities Reading Rooms. Humanities readers tend to use one or two books at a time and use them for close and lengthy study. Consequently, the Humanities Collection is stored below ground and books are delivered to readers on request. Scholars work in daylight introduced into the centre of the reading rooms by way of clerestory and lantern lights housed in the great pitched roofs.

In the Science and Patents Collections in the eastern side of the building, the design is very different. Science readers use a greater volume of documents all at once, but for relatively shorter periods. They require (and have been given) open access shelves from which they can help themselves to books, periodicals, abstracts and microfiches.

The curse of modern architecture is the creation of Kafkaesque interiors caused by over-modularisation and too much symmetry. In the British Library, Professor Wilson has sought to make different areas look different. Thus the two sets of reading rooms do not look alike nor, indeed, do they run parallel to one another. Science and the Humanities are linked by bridges that span the Great Hall.

At the heart of the building is the King's Library. In the 18th and 19th centuries the library received two royal gifts: the old Royal Library, donated in 1757, which was begun by Edward IV in the 1470s and added to by succeeding monarchs, and George III's collection, presented by his son, George IV, in 1823. Professor Wilson has made a practical 'sculpture' of this collection by housing it in a six- storey glazed tower ribbed with bronze uprights and mullions.

It is an act of serendipity which fulfils the requirements of the bequest - which are that the library should be kept 'entire and separate.' The furnishings in the reading rooms are mostly in oak, and while the reading desks and counters were designed by Professor Wilson, the chairs have been designed by Ronald Carter, arguably Britain's best designer of wooden furniture.

The building makes a lie of the complaint that craftsmanship is dead: the quality of work is extremely high. Professor Wilson is a perfectionist. As we stood in the half-built lecture theatre some aspect or other of the ceiling distressed him and he muttered - 'that will have to come down'.

I noticed the workmen eyeing him warily as he conducted me around the site. He relents on nothing. Consequently a lot of men are proud of what they have made.

Professor Wilson's architectural philosophy has roots in the writings and work of the Finnish architect, Alvar Aalto. In essence this means he is committed to the view that architecture is, above all, a practical art: neither purely functional, like technology, nor purely self-expressive, like fine art. His philosophy is demonstrated by his building: rational, flexible and humane.

'Architecture should have the capacity to absorb innovation,' he says, 'and also to celebrate the collective memory by alluding to past motifs.' This the British Library does. The student of architecture will spot allusions to a number of 20th-century architects including Aalto, Le Corbusier and Frank Lloyd Wright. There are echoes too of Alberti and other Italian Renaissance architects, yet none of these references is blatant, ironic or knowing - as they are, for example, in the clever post-modern museums and office buildings so popular in the Eighties.

Professor Wilson is continuing a modern English tradition of architecture as a practical art that Leslie Martin first set in place when he oversaw the design of the Royal Festival Hall on London's South Bank (1951). It is a tradition that has been kept alive by a handful of men such as Sir Denys Lasdun and Sir Norman Foster. It has survived the cacophony of Brutalists, Internationalists, Hi-Technologists, Post-Modernists, Neo-Classicists - and Royalists. It is an approach that, although deeply unfashionable, is designed to outride fashion and to last - and that the British Library looks likely to do.

(Photograph omitted)