The history of painting has arrived at some kind of consensus, however hotly debated, as to how work should be hung. But the history of objects is far more complex, and so the V&A offers two separate series of displays: the Art and Design Galleries show objects of all types produced by a particular period or society; the Materials and Techniques Collections take in objects of all periods fashioned from a particular material - silver, glass or ceramic. The redesigned Glass Gallery, which opened last week at the V&A, is one of these Materials and Techniques collections.
Glass at the V&A used to be displayed in rank upon rank of Victorian mahogany cases. It was tempting, if perverse, to be sentimental about these ill-lit, invariably deserted ceramics- and-glass galleries sequestered on the upper floors of the museum; they seemed to be neutral zones, giving us the objects straight, free from fashionable interpretation. There was even something flattering about the curatorial assumption of knowledge and connoisseurship on the part of the viewer - for the labelling of the objects on their wedding-cake plinths was almost uniformly terse, not to say meagre.
Now that we have the new Glass Gallery it is possible to see that this neutrality was illusory. The curator of Ceramics and Glass, Oliver Watson, and his team have re-presented the collection - chronologically as before, but with its labelling system transformed. There are informative and admirably concise summaries of periods and cultures. Further information on each object can be called up on computer terminals in the gallery, while an introduction to the materials, techniques and history of glass is given by The Story of Glass, a touch-screen computer program that incorporates marvellous short videos.
In one display case we can see the lovely glass made in 12th-century Iran, learn how it was undermined in the 15th century by imports from the more powerful economies of Bohemia and Venice, and be introduced to a curious Persian 19th-century crafts revival. This last was an exercise in romantic nationalism in which functionally mysterious glass was presented by the Persians themselves at world fairs as an imaginative response to the kind of Orientalism so often imposed by the West.
Now that emphases have been adjusted, we learn that the old displays had a hidden set of values, frequently inspired by connoisseurs' fashions in collecting. For instance, 17th and 18th-century English drinking glasses took up a quarter of the old gallery space. This was because from the late 19th century onwards such glasses, and the minutiae of their stylistic differences, have been the focus of obsessive debate and desire among collectors, a passion driven by the subject's typological bible - Hartsthorne's Old English Glasses of 1897. In the new gallery a selection of these glasses occupies just one case and the rest are to be found on a mezzanine floor housing the study collection. Nineteenth-century glass, dismissed as tastelessly extravagant by inter-war curators, is given its due for the first time. The generous space devoted to the Victorian and Edwardian eras demonstrates how voracious European culture at that time could be - engorging and co-opting designs, techniques and decoration from the rest of the globe and from all of history. We may not feel any great tenderness for the period's superlative skills and its all-embracing historicism, but this kind of glass had enormous prestige in the 19th century and its fuller display serves to highlight the radicalism of the Arts and Crafts movement and the modern movement in glass.
There will be those who will find lacunae in the 20th-century section. Why no car windscreens? Why nothing on glass's use in fibre optics or on its integration with sophisticated polymers for all kinds of industrial purposes? In the mid-1980s the V&A gave itself the additional title 'The National Museum of Art and Design'. 'Design' was certainly the buzzword of the decade, but in the context of the V&A it was perhaps misleading. The V&A's roots lie not in industrial design but in what the Victorians called Industrial Art - applied art at its most decoratively complex and technically sophisticated. When it comes to the 20th century, therefore, the museum is faced with a dilemma. We no longer have Industrial Art's equivalent and design historians tend to focus almost exclusively on mass production. Rightly, I think, the collection's curators have favoured the 20th-century studio glass movement - arguably a branch of modern sculpture - over glass's non-domestic industrial applications. This art-based approach is, in fact, more truthful to the museum's origins.
But high technology is everywhere apparent in the planning of the gallery by the architect, Penny Richards of Pringle +Richards. She has provided space for 80 per cent of the collection to go on display, with a mezzanine co-designed with the glass artist Danny Lane. Lane's balustrade is a dramatic tour de force, but the real pleasure of the gallery must be attributed to Penny Richards's decision to go for restrained simplicity. The intellectual sympathy between curator and architect was crucial. 'Not a cross word,' recalls Watson happily.
The result is a gallery in which the objects dominate. Often they are massed together with 19th-century abundance. Yet each piece is fully identified and beautifully displayed. Things become emissaries, illuminating cultures and their tastes and desires. In this corner of the V&A, mystery - in the negative, obfuscatory sense - has been swept away.
V&A, SW7, 071-938 8500, 12noon-5.50pm Mon, 10am-5.50pm Tues to Sun.