Arts: Bacon: the rough guide

Because something has been kept secret, needn't mean it holds a secret. Francis Bacon always said that he never drew, he only painted. But since his death in 1992 a lot of pictures have turned up that undermine this claim. Their value and status are still disputable and the smallish show at the Tate Gallery, Francis Bacon: Works on Paper, is, in some ways, premature. Still, the topic is obviously of note to anyone interested in Bacon, and this glimpse is worth catching. What sort of revelation it offers is another matter.

The drawings at the Tate are dated to about 1957-61. A good moment: Bacon was about 50 years old and - a late beginner - on the brink of what is now seen as his mature style. There are pencil sketches on paper, and oil-paint sketches on paper, and Biro sketches on paper. There are also a couple of examples of his drawings over photographs, where Bacon has taken a photo-reproduction from a book or a magazine and worked over it in paint, sometimes completely obliterating it, sometimes altering it only slightly.

Now, there's nothing here that could be called a finished drawing. Almost all of them are figure studies, quite loose sketches, generally involved with working out some body pose or - if that sounds too anatomically correct - some body shape. Some of them can be related, and quite closely, to paintings; some not. And though it would be presumptuous to say that they're just what you would expect Bacon's drawings to look like, I don't think anyone seeing them will get a big surprise, or say "wow, so that's how he drew".

No. They figure. And as for the altered photos - well, they're interesting, because they show Bacon disrupting an existing image, and in his paintings he's often disrupting his own images - but they're almost not news. We know from photos of his studio and his interview with David Sylvester that he worked from, and among, torn-out and trampled-on photos - Eisenstein film stills, Muybridge motion studies, fine-art reproductions, natural history shots. The fact that he worked on them, too, doesn't seem such a big difference.

I don't say these drawings lack value or enlightenment. They're often graceful in the way that Bacon himself was graceful. They stress the cartoony side of his art, which is always worth stressing. But I do say: if we'd known them all along, I don't think we'd now give them a lot of attention. And if you're looking for revelations, you have to see them in quite another way.

You may remember a TV programme on Channel 4 last year about a large haul of these drawings-over-photos, in the possession of a friend of the artist. They're not in this show. But these, it was said, the Tate had at one point taken an interest in - they were offered without charge, apparently - but then the gallery got cold feet, and the affair was made to sound mysterious and conspiratorial, as if the Tate wanted to hush up the very existence of these pictures.

The problem, I gather, is that another, non-Bacon hand had been detected in the pictures, and that made them dodgy. But now it's thought possible that this other hand belonged to Bacon's boyfriend of the time, and that the drawings aren't so much inauthentic as collaborative. Whatever value that might give them, it seems likely that many visitors will have seen the programme, and could do with more information here. All we get is a tiny mention in the catalogue - "substantial quantities of comparable material have recently been attributed to the artist" - a briskness that suggests the issue remains tricky.

The TV programme, of course, and others, too, have gone on to suggest that the existence of any Bacon drawings is more than tricky, it's damned awkward. It wasn't just that the old dog had been caught telling lies. No one could be surprised or shocked by that, as such. And it's not that Bacon mightn't have had good reasons for keeping his drawings quiet. As David Sylvester says in his preface, he probably didn't think they were much good in themselves, and he didn't want to encourage an irrelevant interest in his creative process, as opposed to his paintings.

Fine. But he may have had bad reasons, too. And what's suggested is that discovery of these drawings touches his paintings very damagingly. By denying them, Bacon was really trying to deny the fact that he had a creative process at all. For didn't he always claim to work in an entirely unplanned and quasi-random manner? And doesn't the power of his art involve a sense of this spontaneity? But these studies and try-outs sink that story - and expose the painting as a kind of con. That's the dreadful secret they reveal.

Not quite. But it is a slightly difficult issue. I think the right answer goes like this. The above line of thought is quite wrong; the existence of the drawings damages the painting not at all. But on the other hand, Bacon himself probably believed something rather like that, and it was a reason for him to deny his drawings. After all, the Bacon myth, partly self-constructed, tends to picture the artist as fighting drunk, flinging himself and several pots of paint at the canvas. There follows a great Andy Capp-style dust-up, a cloud of energy with hands, brushes, rags, and sponges flying everywhere. At the end of it all, things settle, and there on the canvas is the image - the skid-mark of the impact, so to speak.

What I'm getting at is that Bacon did half-want to elide the act of painting. There are all those vivid and memorable phrases in the interviews with Sylvester - about making images straight off his nervous system, or leaving a trail like a snail leaves its slime, or making images that didn't look as though they'd been interfered with. They don't all say the same thing, but the general idea is of images that emanate, materialise, just happen - sort of splurge themselves out of him.

And the thing is, you can half-believe it, too. Bacon's images do have paint skid-mark aspects, and the bodies he depicts have lost their boundaries and they blend into those skid-marks; and then you can imaginatively transfer this feeling on to the painter's own body and its contact with the canvas. This, indeed, is the illusion the paintings often achieve. Bacon is careful to conceal any traces of too deliberated paint-work - and conceals them in the same spirit as he concealed his drawing.

But remember, it is an illusion, and he is careful. True, the paintings have randomly thrown splats of paint in them, and wild strokes, but they are incorporated very cunningly. This spontaneity is, unavoidably, a matter of work. And the existence of drawn studies should be no more of a revelation to us than the "revelation" that Bacon was an extremely skilful operator.

If you really wanted a posthumous revelation about Bacon's art, that would be its subject: Bacon's skills in operation, and operating in one particular area. For there's one notable omission from the Tate's drawings. There are body studies, but there are no head or face studies. I suppose half Bacon's fame rests on what he did to heads and faces. Who wouldn't like to see how that was done? So the revelation I'm imagining is a hitherto undiscovered reel of film, close up on the middle of a Bacon canvas, showing the artist doing his first strokes, his solid modelling of forms and then his blur-smears, dissolves and sudden fade-outs, his chancy, flung blots and splashes and his seamless blending of them into the image, his finishing touches. Bacon-wise, I can't think of a more valuable or curious document. There's almost certainly no such thing. But you never know.

'Francis Bacon: Works on Paper', Tate Gallery, Millbank, London SW1 (0171-887 8000). Daily to 2 May, admission free