Aside from the ecstasy brought by intense religious experiences, considered in the first of these two articles, this trance-like state can most commonly result from physical pleasure. Until recently, professional painters have been cautious to stay within the bounds of what has been deemed decent for their time and society. One way to push those boundaries is to depict classical times.

Lovis Corinth’s painting of Ariadne on Naxos from 1913 shows a group of figures from classical myth on a symbolic, if not token, island. At the left and in the foreground, Ariadne lies in ecstasy on Theseus’ left thigh, as shown in the detail below. He wears an exuberant helmet, and appears to be shouting angrily and anxiously towards the other figures to the right. They are from the later part of this myth, after Theseus abandoned Ariadne on the island. Bacchus then turned up and the couple married.

Bacchic festivities or Bacchanals are another opportunity for a bit of physical ecstasy.

In 1896, Lovis Corinth painted this Bacchanal, with several of its participants staring heavenward with open mouths, clearly in physical ecstasy.

The ecstasy of love and sex was a trickier theme left for the brave or foolish, like Jacques-Louis David in 1809, when Napoleon was approaching the height of his power. David then chose to paint a legend that tells of the love of the poet Sappho for Phaon the ferryman, who plied the waters between Lesbos and the Anatolian mainland. Almost certainly illiterate and hardly a good audience for Sappho’s verse, Phaon’s redeeming feature was his great physical beauty. He was given this one day when he carried Venus in his boat; the goddess was travelling in disguise as an old woman, Phaon didn’t charge her for the crossing, so she returned the favour by transforming his physical appearance. Ovid’s description of Sappho’s affair with Phaon leaves little to the imagination, even down to their lovemaking.

David’s Sappho and Phaon was necessarily not as explicit as Ovid, showing the couple fawning over one another with their recently occupied bed behind them, and an ecstatic gaze on Sappho’s face, resembling those of Corinth’s Bacchantes.

Dante Gabriel Rossetti was more coy in his pen and ink painting of Sir Launcelot in the Queen’s Chamber from 1857, taken from the seamy side of Arthurian legend. While Lancelot is brandishing his sheathed sword at knights on the other side of the door, Guinevere, King Arthur’s queen, already seems to be transported in ecstasy, to the consternation of her chambermaids behind. At least she conforms to Victorian standards of decency in being fully clothed, and doesn’t even expose her feet.

My remaining examples are taken from the transition of the story of John the Baptist’s martyrdom at the whim of Herodias, to the femme fatale of Salome in the closing years of the nineteenth century. Following Gustave Moreau’s startling paintings that changed the original post-Biblical story in The Apparition (c 1876), Oscar Wilde wrote his play Salomé, published in 1893.

Richard Strauss saw Wilde’s play performed in Berlin in 1902, and his opera of the same name premiered in Dresden at the end of 1905. The following year, as an even more immediate inspiration for Franz von Stuck, the dancer and choreographer Maud Allan produced the show Vision of Salomé in Vienna, featuring a notorious version of the Dance of the Seven Veils, and sparking the wave of ‘Salomania’ that swept Europe.

Von Stuck’s Salome (1906) is one of several similar versions. His Salome is the erotic dancer of Wilde, Strauss, and Allan, decked with flamboyant ‘oriental’ jewellery, naked to the waist and in ecstasy. Behind her, in the dark shadows, an ape-like creature grins, and holds out a platter on which is the head of John the Baptist.

Gustav Klimt had already conflated this novel Salome with Judith, who had killed the enemy general Holofernes.

Klimt’s approach was influenced by his decorative experience, and he returned to using gold leaf in what therefore became known as his Golden Phase. In his Judith I from 1901 he emphasises her neck with a broad gold choker studded with gems, and echoed in a golden belt at the foot of this painting. Her glazed eyes are almost closed and her mouth open in overt ecstasy.

In 1909, Klimt followed that with greater ambiguity in what could be Judith II or Salome (1909). Below her is the severed head of either Holofernes or John the Baptist, in a disturbing link between erotic ecstasy and death.

Curtains, drapes of fabric suspended from rails or lines, have been around a long time, but have only recently become popular for providing an internal screen for windows. Although they have other purposes in paintings, they’re primarily used to conceal or to reveal when drawn back. Unusually, they can be depicted as part of the content of a picture, or added to it as a deception, a trompe l’oeil, to fool the viewer into thinking the curtain isn’t in the picture, but is real.

It was Raphael who was probably the first painter to attempt a trompe l’oeil using curtains, in his Sistine Madonna from 1512-13.

Now recognised as one of Raphael’s greatest and most important paintings, it was donated by Pope Julius II to the Benedictine basilica of San Sisto in Piacenza. The two saints shown are Saint Sixtus II and Saint Barbara, whose relics were preserved there. The Madonna and saints are painted superbly, but it’s the rest of the image that is most fascinating. The two cherubs with tousled hair at its foot are gentle touches of humour for a congregation as they looked at this image.

But Raphael’s visual feat is the curtains. He was by now confident that his realism was sufficient to pull off a trompe l’oeil, and fool the viewer into thinking that they were looking at a painting behind real curtains, at least until they got close. Having fooled them once, they’re now more receptive to the image beyond the curtains.

Those curtains also have theological significance: they mark the separation between the physical and spiritual worlds. As they are painted and not real, though, access through them is always open. No one can come along, draw them closed, and stop the ordinary person from accessing Christ. In a world where almost everything else, apart from air, was heavily controlled, this was and remains an empowering message.

Curtains are bold moves in some other religious paintings, including Oleksandr Murashko’s breathtaking Annunciation from 1907-08. Apparently, he was first inspired to paint this when he saw a girl part light curtains to enter his house from the terrace outside, and saw a parallel with the entry of the Archangel Gabriel in the Annunciation.

Their role in Dante Gabriel Rossetti’s Girlhood of Mary Virgin from 1848–9 is less convincing. This contains some archaic devices, such as the gilt and lettered halos, and an oddly-proportioned angel, but shows what Rossetti envisaged might have been the pictorial reality of the Virgin Mary during her youth. She works on embroidery with her mother, Saint Anne, while her father, Saint Joachim, prunes a vine. Those are shown realistically with an abundance of symbolic objects, but the curtains seem merely a background.

A curtain formed from an outsized handkerchief is concealing in Raphaelle Peale’s Venus Rising From the Sea – A Deception (c 1822). This was a visual criticism of the small-minded attitude to the display of paintings of nudes at the time.

With curtains concealing what shouldn’t be seen, they provide a means for the voyeur to peep through them.

The story of Susanna (or Shoshana) and the Elders is told in the Old Testament book of Daniel, chapter 13, and centres on voyeurism, blackmail, and justice. Susanna was a beautiful married woman who was bathing in her garden one afternoon, having dismissed her servants. Two lustful elders spied on her, and as she returned to her house they stopped her, and threatened that, unless she agreed to have sex with them, they would claim that she had met her lover in the garden. Being virtuous, Susanna refused their blackmail, and was promptly arrested, charged with promiscuity, and awaited her execution.

It was only after the intervention of the young prophet Daniel that the elders’ conspiracy was revealed, Susanna was acquitted of the charge, and the elders executed instead. Lovis Corinth’s early Susanna Bathing from 1890 adopts a traditional approach, where Susanna is seen in the flesh, being spied on by a peeping elder from behind a curtain.

Pedro Américo’s Faust and Gretchen from 1875-80 uses this in the context of the seduction of Gretchen in Goethe’s Faust. The shadowy figure of Mephistopheles is eavesdropping behind the curtain at the right, and white lilies, a symbol of her virginity, lie fallen on the floor.

While peeping is implicitly non-consensual and unwelcome, curtains can also be used for revelation.

One of Millais’ last paintings, before his death the following year, was Speak! Speak! (1895), which is also one of his most enigmatic. Millais’ son reported that this scene is set in ancient Rome. The young man had spent much of the night reading through the letters of his lost love. At dawn, the curtains were parted to reveal her, dressed for her bridal night, gazing upon him with sad but loving eyes. The title of the painting is therefore the words that he said to her spectre.

The mere presence of curtains denotes separation, particularly that between performers and their spectators.

Antoine Watteau adds a scarlet curtain both for colour and as the conventional separator between The Italian Comedians (1720) and their audience.

Ludwig Knaus shows the scene Behind the Curtain of a small itinerant circus in 1880. Performers were often colourful in both their costume and character, with many incongruities, such as the clown seen in the centre feeding a baby, and looking straight at the viewer. Their curtain is also rough and ready.

Grant Wood’s Parson Weems’s Fable from 1939 refers to Mason Locke Weems (1759-1825), who wrote the first biography of George Washington shortly after the latter’s death. This contains several apocryphal stories, including the legend of the cherry tree, which didn’t appear until its fifth edition.

According to this, when Washington was six, he was given custody of a hatchet, which he used to cut through the bark of a superb young English cherry tree. When this was discovered the next day, Washington’s father asked the boy if he knew who had killed the cherry tree, to which George Washington admitted his guilt, saying that he couldn’t tell a lie. His father was overjoyed at his son’s honesty. Sadly, the story is generally considered to be a fabrication.

Wood’s ingenious treatment places Parson Weems at the right, holding open a stage curtain, as if narrating the story to the viewer.