The ability to play an instrument, and preferably several (though not too well) was a desirable accomplishment in both men and women, and because music is mathematically based it was often seen as a nobler art than painting. So when Frans van Mieris the Elder painted himself strumming a cittern he was showing himself as standing above the artisan. Gabriel Metsu may well have been a keyboard player because the same highly decorated virginal appears in at least four of his pictures-it was too expensive to be a mere prop. The scientist Constantijn Huygens collected a wide variety of instruments for his own use, even asking Nicholas Lanier, Charles I's leading musician, for purchasing advice. The exhibition includes a clutch of period instruments as well as the printed songbooks that popularised the latest compositions.

While artists clearly relished the opportunities offered by musical instruments to display pattern, texture, and light falling on wood, ivory and tortoiseshell it was music's role in courtship that attracted them the most. In this context Vermeer was just one performer among many. His guitar player looks off to the side-lips parted in mid song — at a figure unseen by us. Who but a man, though, would warrant her yellow silks with ermine trim and an expression that carries more than the pleasures of music making? In the Queen's Music Lesson a man stands next to the virginal-playing young woman. Her head, reflected in a mirror above, is turned slightly towards him, although whether to look at her fingers or glance at him is unclear: is his raptness the result of her music or her closeness? His other keyboard-playing women look out frankly at the spectator, inviting us in to join them in a duet that may, just possibly, be not simply musical. In Vermeer's highly attuned paintings the harmony of string instruments is subtly but unequivocally likened to the harmony of lovers' hearts.

The exhibition reveals other complementary notes too. Wind instruments being played rarely occur in these genteel interiors because the effort distorts the face of the musician. Viols and flutes nestle next to skulls and hour-glasses in vanitas still lifes: the sweetness and transience of music perfectly representing the arc of life itself. Songbooks are a familiar presence, not just because of their practical role but also because they were frequently exchanged as lovers' tokens. And the instruments themselves hold second meanings: the shape of the lute meant that it was recognised as a symbol of female genitalia and the curves of violins were understood to mirror the female form. If the songs work their intended spell, the hands in these pictures will soon press and caress flesh rather than keyboards or strings.

Any exhibition that brings together more than a couple of Vermeers is well worth seeing and this one places him in very good company. Its real achievement though is in separating a particularly resonant melody from among the superabundance of Dutch painting.