Longhi, Pietro: The Presentation (c1740)

The raked stage was once a favourite feature of productions of Shakespeare and Wagner. It rose up, away from the audience, like a ramp. Sometimes, the gradient seemed immensely steep, like an impossible hill in a dream. The slanting set was a metaphor for instability, struggle, crisis. Lear and the Fool, Wotan and Brunnhilde, some how they kept their footing. A feeling of literal precariousness and physical danger was often part of the drama.

With a picture that is done in perspective, the floor or street that recedes from the viewer also "rises up" towards the middle of the image. The inverted commas are there because, of course, it isn't meant to look as if it is rising. It only means that the view is seen from a point above ground level, and the ground is therefore visible. But since the view is projected on to a flat surface, there is the risk that the ground stretching away will look more like a sheer slope.

There are pictures that give this impression. They make receding ground resemble a raked stage. This happens because they overlook a key rule of perspective, which says that things that are nearer should be bigger than things that are further. If you neglect that, and make all your figures, near and far, the same size, and then position the mat various distances along the receding ground, they will not look like figures who are themselves receding. They will look like figures positioned on a steep slope, some higher up than others. They will make a supposedly level floor look like a ramp.

It is a classic perspective mistake. But when it happens, it may not be obvious whether it is an error or an effect - whether the artist just hasn't mastered the rules, or is deliberately bending them in order to generate (as with those theatre sets) a sense of difficulty and crisis. For example, in a highly charged social situation.

Enter Pietro Longhi. This Venetian painter is a singular figure. His work fills a gap. There are several well-known omissions in European painting: hardly any paintings of sex, for instance, none of childbirth. Longhi's work makes you realise that there are also very few pictures about the perils, pretences and anxieties of social interaction.

Novels and plays and operas are full of sticky social situations. Paintings are not. They have plenty of heroic moments, very few awkward moments. But the theme can be perfectly visual, as demonstrated by Longhi. The social milieu he depicts is filled with flirtation and deception, hints and secrets, masks, fans, glances, gestures, nudges and whispers and winks - all happening in a public realm where such surreptitious carryings-on are acknowledged by everyone, but where appearances and standards must be kept up. The scene is sometimes the street, and sometimes the drawing room.

In The Presentation (detail above), it is the latter. Two figures, a gentleman and a lady, approach two other ladies. There is hierarchy here. Those two ladies are at home (the children peep out behind them). One of them, putting her fan to her chin, is superior to the other. They're mother and daughter, perhaps. In fact, this lady is the senior figure in the room. It is to her that the gentleman is introducing the lady in the dark blue dress. The pair have their backs to us. Their faces can only be imagined. But the situation is clearly delicate.

Longhi's doll-like figures emphasise the highly artificial and game playing nature of this world. Yet, in this scene, there's a sense of something very serious and possibly dangerous in process. The hostess ladies stand in blazing light. The approaching pair are in darkness. The man's coat swirls as he turns, but stiffly. It looks like slow motion, or the kind of impededmotion, as if through a heavy medium, that happens in dreams. You are made to feel that the approaching pair are paralysed by the anxiety of the encounter' or that, at this critical moment, as they begin to bow and curtsy, they experience every millisecond as it passes.

Crisis. Suppressed hysteria. And it is the floor that is crucial. It rises steeply upward. Longhi has perpetrated the classic perspective "mistake", making all of his figures, nearer and further, on the same scale so that they seem to stand higher and lower. The pair are several heads lower. They must make their approach up a gradient that, at some points, looks unclimbable. They might slip and fall at any moment.

It must be an intended effect. The slope stands for hierarchy, for uncrossable social distance, for precarious status, for the danger of the moment, for sheer insecurity and disorientation. The area of empty floor in the bottom left is without any clear sense of plane. It's just a void, into which the little dog in the corner gazes up in amazement.

THE ARTIST

Pietro Longhi (1702-83) is a disparate talent within 18th-century Venetian art. In style, he is a delicate, sometimes naive painter' in social consciousness, he is a sophisticate, depicting the highly self-conscious, playful little world of Venetian high society. Ladies and gentlemen, in their masks and tricornes, intrigue in the living theatre of carnival, while street life is full of quacks and mountebanks.