FOR an art collection to share its entrance hall with a tyr- annosaurus might seem especially risky these days, when museum curators are increasingly likened to extinct species. At the National Gallery of Wales, however - where the archaeological and scientific collections are still housed in the same building as its paintings and sculpture - the conjunction is gracefully carried off: the dinosaur models are as easy on the eye as the Rodin bronzes. The first phase of a redecoration and building programme at Cardiff has recently been completed, and the refurbished east wing housing a part of the art collections is now open to the public. Smith and Brewer's handsome Edwardian building, with its Doric colonnades and banded rustication on the exterior, its shallow domes, balconies and chunky cornices inside, was originally planned to surround four sides of a central courtyard, but the north wing, which would have housed two further floors of art galleries, was never constructed. The new scheme, which is scheduled for completion in 1993, does not follow the original plan: instead, the east and west wings will be linked with a two- storey infill, not quite touching the old facades, but with bridges through on all sides. The architects are the Alex Gordon partnership. The new rooms on the upper storey will contain the bulk of the later nineteenth- and twentieth- century collections; while a pavilion completing the east wing in style will terminate the suite of first-floor rooms already revamped. This twenty-five million pound project is the largest publicly funded museum building campaign in the British Isles.

The re-decorated galleries of the east wing convey an un-slavish respect for the old building with one or two contemporary touches. In line with 1980s taste, partitions have been removed, vistas opened up, picture-rails restored, and some double-hanging introduced - although unfash- ionably low at the lower level. Wall coverings for the old master galleries are dark - muddy grey green or deep red damask. But handsome benches and chairs with a faintly Celtic feel have been commissioned from a contemporary craftsman. All the pictures are glazed, which obviates the need for ropes or period furniture.

One of the most enjoyable of the new spaces is the luminous quadrant above the lecture theatre, cleared of offices to provide room for British art from 1850 to 1930. Here Welsh-born painters - Burne-Jones, Brangwyn and the John siblings - describe the outer curve, their English contemporaries the inner - Whistler, Sickert, William Nicholson. The Tate has generously lent Gwen's contained self-portrait and her brother's swashbuckling Mme Suggia to round off Cardiff's own strong John holdings. In the eighteenth-century room native genius (Thomas Jones, Richard Wilson) complements native taste, represented by the ever-increasing items from Sir Watkin Williams Wynn's Collection (see p.450).

At their foundation in 1907, the art collections of the National Museum were conceived as a showcase of Welsh achievement, and this tradition of acquisition has been finely maintained. But, as a result of a sequence of benefac- tions - the De Winton Collection of ceramics (1918), the W. GoscombeJohn bequest (1938-46), and, above all, the impressionist and post-impressionist collections of the re- doubtable Misses Davies (1951 and 1963), the museum's European reach has happily exceeded its national-provincial grasp. Perhaps most notable in the last twenty years have been the sixteenth- and seventeenth-century acquisitions: apart from two Davies Botticellis, almost all of the paintings in the first two rooms have been acquired since 1970. With the comparatively generous budgets and pre-boom prices of the 1970s, it was possible to buy good Italian pictures on the London art market with relative ease. But the eighties too have brought their plums - the Allandale Claude (1982), the Holkham Aspertini (1986), a Palma il Vecchio in a magnificent Sansovino frame (1987), and half Poussin's Finding of Moses (which has made its first pilgrimage from Trafalgar Square to Cathays Park to cel- ebrate the opening). Timothy Stevens and his colleagues have cause for quiet satisfaction.

Further reflections on past and present acquisition poss- ibilities are prompted by the re-opening of the Barber Institute Galleries at Birmingham University, where Hamish Miles, Barber Professor since 1970, has hung the collection for the occasion in chronological order of pur- chase. The galleries have been re-roofed, air conditioning introduced (though the effects were not apparent in the tropical heat of opening day), and the space for pictures extended by top-lighting the former Tapestry Gallery.

The Barber is exceptionally fortunate among university museums in having a large private endowment which has shielded it from the cheese-paring that has so afflicted the Ashmolean and Fitzwilliam. In the fifty-four years since the first work was bought at the Oppenheimer sale (a Fra Bartolommeo drawing) an impressive collection of Old Masters has been built up. In 1967 the Trust Deed, which had previously ruled out works produced after 1900, was amended to allow the purchase of works not less than thirty years old, and works by LUger, Gwen John, Magritte have recently been added.

The temporary arrangement of the galleries exposes the weaknesses as well as the strengths of the first occupant of the Barber Chair, Thomas Bodkin. Against his superb Poussin, Rubens, Gainsborough, Murillo, Bellini and Degas must be set the occasional dud Constable, Rembrandt and Gaugin - not to mention 'Goya's mother', oddly resembling an American primitive. Ellis Waterhouse's purchases from 1952 to 1970 took the collection down less explored byways of mannerism and baroque. Under Hamish Miles the Institute has bought less copiously, but with great distinction, adding fine works by Vigde le Brun, Roubiliac and Bassano. Rather surprisingly, no works on paper - a frequent standby of university museums - have been acquired since 1970.

With the support of the Barber Trustees, the University has recently decided to expand the r6le of art history in the arts faculty. The newly appointed Barber Professor, Richard Verdi, will have the enviable task of founding his courses on the collections acquired by his predecessors. It is an ideal opportunity for re-affirming object-based art history and the university is to be congratulated on its vision.