Exhibitions: Signs for slow readers

HOW LONG does it take to look at a picture? One can't say, of course - a moment or a lifetime. But while most pictures can, in some sense, be taken in almost at a glance, there are some that simply cannot. And you see, at a glance, that Simon Lewty's pictures are of that kind. They're pictures that ask not to be viewed, but to be pored over, detail by detail. One reason is obvious enough: they're covered in words.

A retrospective of Lewty's work, concentrating on the last 10 years, is now touring under the title Terra Incognita. Lewty is 51 and not all that well known himself, certainly not a member of any established tendency. It's borderline whether strictly speaking, he's a visual artist at all. But the pictures, though weird, are not unknown territory. They resemble many familiar not-purely-visual things - cartoon strips, old maps, diagrams, illuminated manuscripts. In fact, they look like all of these things, jumbled together.

Every kind of graphic sign-language is employed, and none takes precedence. Blocks of closely hand-written script, bearing obscure prophetic messages, assume a pictorial life alongside scenes of buildings, men, real and invented creatures. (Lewty's drawing is very variable: sometimes beautifully precise, sometimes - as in the detail shown here - like a horrid offspring of Maurice Sendak.) The parts are in free association. There are none of the usual relationships between picture and caption, text and illustration, diagram and label. You can't say what's central and what's marginalia. Trails of marks lead between one corner of the picture and another. The eye has no orientation - it can move left, right, up and down, or try to decipher the palimpsests of words and images, the invented words and alphabets, the strange sigils and symbols. There's a mass of clues and paths in which some kind of fable or revelation seems to be concealed.

What I like about Lewty's work is this all-over and many-layered readability. His way of making pictures has a potential for a large and complex informativeness (a good thing in art, and a rare one at this moment, when resonance and evocativeness are at a premium). It has that sense of accumulated intrigue you find in the heavily graffitied wall of a public toilet, in carved-up school-desks, or a book that's passed through the hands of many annotators and doodlers. This appearance of something to be puzzled through at length is very attractive too; but also dubious.

The question is whether it is only an appearance, merely evocative itself. For what Lewty's pictures call to mind above all are the obsessively involved and detailed works of certain 'outsider' artists, those documents of deeply strange souls, whose fascination lies nevertheless in the fact that they did make some kind of sense to their makers. But Lewty himself, though hardly mainstream, is art-trained and a more or less conscious operator. His pictures are not really 'documents' in that way - just as (another of their attractions) they're not really old, but have been given an aged look. He knows his sources and their devices. And one suspects an expert pasticheur of the weird, producing a show of secrecy, a designed mysteriousness. We can appreciate it, as we appreciate old maps. But the primitive cartographers who wrote 'Terra Incognita' would actually have preferred to know what was there.

Yet I wouldn't want to set down Lewty's work as simply charming but faux. There is a point at which pastiche, done with sufficient conviction, becomes an authentic language of its own, and Lewty does reach that point. At least, if you found these pictures in a pile of old stuff in the loft, I don't think you could tell the difference. Then you'd have the task before you of trying to work it all out. It would take ages, much longer than you can reasonably spend in a gallery. In fact it would be much the best way to come across them.

'Terra Incognita' is at the Castle Museum, Nottingham, (0602 483504), till 8 Nov, and the Mead Gallery, Warwick University, Coventry (0203 524524), from 16 Nov to 19 Dec.

(Photograph omitted)