Poems made in pen, ink and water

One of this century's finest poets, Elizabeth Bishop, published just four books over four decades. Her friend Robert Lowell admiringly teased: "Do / you still hang your words in air, ten years / unfinished, glued to your noticeboard, with gaps / or empties for the unimaginable phrase ...?" A Bishop poem feels exactly as well made as that but also brings you the excitement and immediacy with which she first met her subject. Even her landscapes are all-action events.

Bishop also painted, declaring herself a "genuine primitive". She worked in watercolours or pen and ink, media that do not allow for the doubletakes and adjustments visible in her writing, as if she were thinking out loud. These vivid, playful, often occasional pictures signal "off duty". Her subjects are contained: a building, the corner of a room or a bunch of flowers. The extraordinary trajectories of her poems, their momentum and swerves, are very different from this stillness. Here, her mirrors and windows are blank.

William Benton's idea of collecting and publishing these pictures was inspired. They are illustrative rather than painterly, but it is what they illustrate of Bishop's poetics that makes them so absorbing. In a fine introduction, Benton recalls how a dozen pictures turned up in a folder at Vassar (Bishop's alma mater) looking like "pressed butterflies" and how he traced others to her friends, whose eccentricities, hauteur and bons mots give us a glimpse of Bishop's world - one of character and characters.

Like Chagall placing a bunch of flowers at the centre of a picture in which two lovers fly away, Bishop introduces dramatic tension to conventional subjects through unexpected emphases: a figure afloat in its setting, pale wash against the detailed grain of the floor; the pattern of a bedcover rather than the sleeper's face; the shadow of a chandelier. In Tombstones for Sale, the white slabs are vague ghosts among the hard vertical lines of a fence, wall and door, while the attention is stolen by a tree in fiery bloom.

Bishop can make her subjects reveal themselves, "like the tipping of an object toward the light", through dizzying misalignments or odd perspectives. Harris School, a castellated brute of a building, is upset by two trees tilting to the left in front and two kites flying to the right behind. A bicycle, tipped all ways, lies plonked in the foreground. The marvellous Interior with Extension Cord leads the eye into a corner while the lines of wall, floor and ceiling flail wildly out. The wobbliness of it all is her argument with what the eye expects, how the eye wants to tidy up what is really seen.

Pattern, construction and design are attentively rendered. Chinese white brings out the bones of the Palais du Senat while floral, checked and striped cloth are patiently detailed. In Cabin with Porthole you can see Bishop figuring out how the porthole stays open, how the fan is fixed to the wall, why the objects on the table don't fall off. This is like an actual version of the imagined circuitry and wires that turn night into day or bring down the rain in her poems.

Just as she integrated natural and heightened language, Nova Scotia Landscape is a conventional scene in which a fence hurtles up and down hills like a runaway train and the sea is hard dabs of lavender. Her use of colour is as subtly dramatic as her style of composition. She had a passion for it, beginning with classroom maps and paint samples as a child. The skies in her pictures radiate or oppress, never blue but ranging from apricot to old envelope. She is as particular and demanding of colour as she is of all sensory effects.

An admirer of Kurt Schwitters and Joseph Cornell, Bishop made an austere

Feather Box and another containing a child's dummy and sandal, schoolgirl cherubs and butterflies. She was a collector and a gallery-goer, and explored the visual mediation of subject into image in her work. You can see Klee or Vuillard in her paintings and her poetry, not because she imitated them but because she liked them and saw what they saw.

What excited her was the visual impact of convicts in their black-and- white stripes working among brilliant tropical shrubs or a dog in Miro's Farm, barking at footprints. As Benton says, and this delightful book shows, Bishop was "her own best influence".