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In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: The painting shows the moment from Summer in which Musidora, having removed the last of her clothes, steps into "the lucid coolness of the flood" to "bathe her fervent limbs in the refreshing stream". Damon is not shown; instead, Etty illustrates the scene from Damon's viewpoint. By placing the audience in Damon's position, Etty aimed to induce the same reactions in the viewer as Damon's dilemma as described by Thomson; that of whether to enjoy the spectacle despite knowing it to be inappropriate, or to follow the accepted morality of the time and look away, in what art historian Sarah Burnage has described as "a titillating moral test for spectators to both enjoy and overcome".The pose of Musidora is based on that of the Aphrodite of Cnidus and the Venus de' Medici. It is possible that Etty was also familiar with Thomas Gainsborough's Musidora, which shares similar elements. Gainsborough's Musidora, his only large nude, was never exhibited in his lifetime and remained in private hands until 1847, but Etty was familiar with its then-owner Robert Vernon and may have seen it in his collection.
The setting for the painting is a pool in the grounds of The Plantation, a house in the village of Acomb, near York. The Plantation was the home of his close friend and patron the Reverend Isaac Spencer, vicar of Acomb, and its grounds were a scene Etty had previously painted. In 1846 Etty bought a house in York for his retirement; Burnage speculates that Etty chose Acomb on the grounds that a view of York was quintessentially English.Although Etty had traditionally worked in the Venetian style of painting, with rich colours and detail, for Musidora he adopted a much softer and earthier palette, although his use of reflected light on flesh is derived from Venetian styles. He moved away from Rubens, who up to this time had been his greatest influence, and closer to the style of Titian. This is likely owing to the nature of the subject matter. Until then his history paintings had primarily been of themes of classical mythology, and took place in brightly lit Mediterranean settings. The Seasons, by contrast, was seen as an explicitly English work, requiring a more muted palette to deal with the typical lighting conditions of Yorkshire.
Output:
What is the first name of the person whose only large nude was never exhibited in his lifetime and remained in private hands until 1847?