IN HIS maturity Abraham Bloemaert (1566-1651) was the foremost exponent of Catholicism in Dutch art, a status he achieved without ever going to Italy. The prime expression of his religious art- only one of the many facets of this comprehensive master - was in his altar-pieces. They have received scant and uneven attention; while a few are in museums and have been studied in recent years, others are virtually inaccessible and have remained unknown.

THE EXHIBITION, entitled Palaces of Art, which moves this month from Dulwich Picture Gallery to the National Gallery of Scotland, is devoted to the development of purpose-built art galleries in Britain from 1790 to 1990. It comes at an opportune moment, when new galleries have been built and others are in the planning stage. In this somewhat parochial overview we come full circle, with John Soane's Dulwich among the earliest (1811-13) provid- ing a design model for the most recent - Robert Venturi's Sainsbury Wing at London's National Gallery (1991). This exhibition demonstrates the genesis of the top-lit gallery for the display of paintings from its beginning as an adjunct to the gentleman's private residence to its public rôle up to the present day as a place for the enjoyment of a larger public. Two factors are immediately apparent. The domestic arrangement allowed diverse objects and furnishing into the room, avoiding the largely empty spaces with paintings lining the walls which are found in the majority of galleries in the public domain. Space was also available for many of these early top-lit galleries to be at virtual ground level without the need for that penitential climb up stairs, generally of marble, to the shrine above. Happily, Norman Foster has managed to turn even this into a pleasurable experience in the Sackler Galleries (1991) at the Royal Academy, by providing an unclaustrophobic lift and glass tread stairs in an open space. Where the public gallery is in a former residence, such as the Wallace Collection in Hertford House, it is possible to achieve congenial furnished interiors sympathetic to a picture hang, but with the disadvantage in this case of daylight entering solely from side windows.

DURING the negotiations which led up to King Henry VIII's marriage to Anne of Cleves, much importance was placed on obtaining accurate portraits of Anne and her younger sister, Amelia. As the episode is well-known, a summary here will suffice. In the spring of 1539 portraits of the sisters were shown by Olisleger, the chancellor of the court of Cleves at Düren, to the two British envoys, Nicholas Wotton and Richard Beard, who objected that they would not be able to vouch to the King for the likenesses, having not seen the ladies themselves at sufficiently close quarters. After a sharpish exchange, Olisleger promised to deliver the portraits to Cologne, whence Wotton and Beard would send them to England. This appears not to have occurred, for a fresh attempt was made in late June of that year to secure the portraits, with an opinion about their verisimilitude. Beard was in London in July, but it is not known whether he brought the pictures with him: if so, they cannot have satisfied Henry, for Beard was immediately sent back to Diren, accompanied by Holbein who had instructions to paint both sisters. His painting of Anne - the celebrated portrait on vellum now in the Louvre (Fig.21) - was brought back to London by the end of August.

DURING the last decade a small picture of a coastal scene, painted on copper (Fig.28), has generally been accepted as an early work by Jan Brueghel the Elder. The picture, previously attributed to Paul Bril, was published in Klaus Ertz's mono- graph of 1979 as the earliest ofJan Brueghel's extant oil paint- ings, said to have been produced in Italy before 1594 under Bril's influence. The painting was presented as such in the great Brueghel exhibition at the Palais des Beaux-Arts, Brussels, in 1980, and was discussed again in 1982 as a significant example of Jan's early work.

NEW documentary evidence sheds light on the so-called Portrait of a gentleman (Fig.31) in the Galleria Nazionale at Parma, and on its painter, Johann Gersmueter. Executed on 1st April 1606, the portrait is Gersmueter's only known work, and is signed on the base of the column at right as follows: IO.ES GERSMUETER ME FE. A.O 1606 P.0 APR. Two further portraits, ordered by Ranuccio Farnese Duke of Parma, are recorded in notes of payment in the Archivio di Stato, Parma, dated 1st and 3rd June 1606, to a 'pictor fiamengo' named 'Giovani Gersementor, but both remain untraced even in the inventories of the Farnese Collection. One represented Cardinal Odoardo Farnese, the Duke's brother, and the other Prevosto Zoboli, one of the Duke's close friends. The two documents, both of which are signed 'Johan de Gersmueter', together with the dated picture at Parma, indicate that in the short period between April and June 1606 the Flemish artist executed at least three portraits for the Farnese. A hitherto unnoticed wax seal showing a fleur-de-lis encased in a shield, with the number 431 incised on it, preserved on the back of the canvas in Parma, allows the picture to be traced in inventories of the Palazzo Farnese in Rome. According to those of 1641 and 1653, it was placed on the wall of the upper library, and is described as 'un quadro in tela senza cornice col retratto in piedi di Giangiovetta nano del Duca Alessandro'.

THE identity of Jacob van Ruisdael's teacher has always been something of a mystery. Although his father, Isaack, has been mentioned as his first instructor in the art of painting, it has hitherto been impossible to assess this claim because of the difficulty of assembling a corpus of works securely attributable to him. In his review of the Jacob van Ruisdael exhibition held in Cambridge, Mass. and The Hague in 1982, however, Christopher Brown mentioned a large painting, then on the London art market, of a Courtyard with a woman laying out linen (Fig.32) which bears the signature 'IVRuisdael 1645', grouping it with two others (Figs.33 and 34) as works by Isaack. The same painting was reproduced by B. Haak in his book on seventeenth-century Dutch painting published in 1984, though with some hesitation as to whether Isaack was indeed its author. The picture, which can be identified as a view in the city of Naarden, has now entered a private American collection where it is accessible to scholars, and provides a useful starting-point for a fresh assessment of Isaack's œuvre.

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