ON 10th July the Sainsbury Wing at the National Gallery opens its doors, only three and a half years after the foundation ceremony - a remarkably swift conclusion to the disputatious decades since the Hampton Site was ac- quired by the Government in 1958. The speed of construc- tion has been due not only to novel building technology, but also to the experience of the Sainsbury brothers, who combine firm control and liberality in the proportions necessary for true architectural patronage.

About the exterior of Robert Venturi's building there is much - not all of it favourable - to say, but since it looks remarkably like its model, discussed in these pages in 1987,' it can be left to the mercies of the architectural critics. Concern for the security of the ground-level en- trances has been met by the erection of handsome jig-saw railings, which have the added merit of veiling the half- eaten appearance of the south-east corner - one of the more tiresome and dated hallmarks of post-modernism.

First impressions of the interior are that the entrance hall is somewhat low and gloomy, the basement exhibition rooms over-tall and boxy. (The spirit sinks at the thought of the Gallery being trapped into the blockbuster treadmill by the mere existence of these unlovely spaces.) Much has been sacrificed to make the restaurant the most outward- looking and welcoming ambience in the building, currently enhanced by Paula Rego's amiably sinister feminist murals. No doubt Venturi counts on the staircase to win immor- tality: widening as it ascends to the galleries, narrowing as it plunges to the basement, the first tract ornamented by free-floating 'cast iron' arches, the second by brutal frag- ments of outsize cornice.

Mercifully the main-floor galleries are largely free of such ponderous whimsy - apart from the Michelin-man bases of the columns which flank the initial east-west vista (Fig.2a). The sixteen rooms, housing works from north and south of the Alps painted before 1510, are disposed in three parallel sequences: the higher central one is designed as an axial promenade through Dulwich- like arches, but intersects through side-doors with the east and west suites, where the openings are artfully staggered to avoid banal enfilades (Fig. 1). In the east range (which contains the most congenial rooms) windows giving on to the staircase afford Venturian 'layered' glimpses ofWilkins's main building.

The architect's stated aim in the galleries is to evoke, without direct citation, Brunelleschi's church interiors and a generic early renaissance palazzo. This works surprisingly well. Although the pale grey walls and pietra serena trim are not Urbinate or even Florentine in detail, they provide a sympathetic framework for the early pictures. Grey stone corbelled shelves or plinths furnish acceptably simple sup- ports for the larger altar-pieces. While elsewhere in the building the repeated shades of grey can become enervating, here they are refreshed by the skilful and varied top- lighting. Etched glass clerestories surmount the high coves above the cornices. Through these filters natural light, monitored and changed every two hours by electronically controlled louvres, and enhanced by tungsten halogen lamps and recessed track spotlighting. The natural light is so good that it should be possible on some days to satisfy an informed distaste for the artificial.

For hanging the collection, one of the great advantages of these rooms over those of the old building is that the early paintings regain their physicality as three-dimensional objects. Altar-piece carpentry and

all'antica carving come alive, especially important since it is impossible in a top-lit gallery to recreate the polychromed beamed or coffered ceilings and the inlaid wainscoting of so many fifteenth- century Italian domestic interiors. The Botticelli room, where the Mars and Venus and the early Adoration of the Magi are hung over painted cassoni, succeeds brilliantly in recalling, without attempting to 'recreate', the Quattrocento camera. In another particularly successful room, which has immediately taken on an almost definitive status (Fig.2b), Masaccio, Gentile, Lorenzo Monaco and Sassetta are united in a way which at last does justice to the gothic strand in the early Quattrocento, while affording an axial glimpse through to the victory of geometry over nature in Uccello's Rout of San Romano. The reunion of the early Flemish and German pictures with the Italians is an unqualified blessing. Although statistically outnumbered, and subjected to Ital- ianate triumphalism in the architecture, the northern paint- ings more than hold their own. Indeed, the prominently placed and beautifully hung German room is bound to win new admirers for these somewhat neglected pictures. The discreet mingling of Antonello da Messina with Bouts and Memling makes Vasari's point about oil technique, but we have already had the opportunity to make con- nexions between Lippi, Piero, Tura and the north, by judicious side vistas through earlier rooms.

The present hang has been the fruit of some changes of mind and of curatorial staff since the initial conception, of which, however, some fixed points remain built into the architecture. Thus Piero's Baptism at the south-west corner is recessed into a blind arch and forms the centre of a shrine to the twentieth-century's preferred Quattrocento master, so presciently secured by Eastlake. Parallel to it on the south-east side is Van Eyck - the cold north signalled by the use of wooden skirting - but less-well served by one of the most purposefully irregular rooms in the building. It must be said that the eccentricities of Venturi's plan, together with some early curatorial decisions, have taken their toll on the picture hanging. There is scarcely a right angle to be found in the plan, and the anachronistically baroque false perspective which cuts an east-west swathe through three of the galleries would have put an intolerable strain on any picture chosen to occupy its focal point. The choice of Cima's Incredulity of St Thomas, which fell into the Grand Canal in 1820 and is now a monument to the inpainting skills of the Conservation Department, was perhaps a self-indulgent irony when no space has been found to hang any altar-piece by Signorelli.

Another early decision which has been fateful for the hang was to house the Leonardo cartoon in a darkened closet off the first room. This has two consequences. First, the chronological sequence of the Sainsbury Wing has to begin and end in this same room, which thus becomes a breathless precis of Vasari's Lives, from Margaritone to the Madonna of the Rocks. Secondly, in the Gallery as a whole, the High Renaissance has been chopped in two: students of Raphael will be constrained to walk from the cool grey emulsion of room 60 across the bridge to the old building and the dark red fabric of room 8 to link the Ansidei Madonna to his portrait ofJulius II. Michelangelo, whose Entombment almost certainly pre-dates all of the paintings by Raphael owned by the National Gallery, is hung as though he were a later master. The result is a curiously Ruskinian view of early Italian art.

In 1857 Ruskin was asked by one of the many nineteenth- century committees investigating the National Gallery whether the working man preferred 'Art up to the time of Raphael or down from the time of Raphael ... the Bolog- nese School, or the early Florentine School'. Ruskin's stern reply was that 'my working men would not be allowed to look at a Bolognese picture'.2 Whereas the revulsion felt by writers in the Art Journal in the 1850s for the 'Orcag- nesque horrors' in the National Gallery seems incompre- hensible to us today, it is not so long since a Director felt that to ask his Trustees to buy a painting by Guercino would be a hopeless task. In the supplement after p.000 we publish the catalogue of a small exhibition at the National Gallery of paintings by Guercino in British col- lections. That it is not even smaller is due to the enthusiasm of Sir Denis Mahon, to whom this issue, which deals largely with seventeenth-century Italian art, is gratefully dedicated.