Given the task definition and input, reply with output. 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 Boydells focused all their attention on the Shakespeare edition and other large projects, such as The History of the River Thames and The Complete Works of John Milton, rather than on lesser, more profitable ventures.  When both the Shakespeare enterprise and the Thames book failed, the firm had no capital to fall back upon. Beginning in 1789, with the onset of the French revolution, John Boydell's export business to Europe was cut off.  By the late 1790s and early 19th century, the two-thirds of his business that depended upon the export trade was in serious financial difficulty.In 1804, John Boydell decided to appeal to Parliament for a private bill to authorise a lottery to dispose of everything in his business.  The bill received royal assent on 23 March, and by November the Boydells were ready to sell tickets. John Boydell died before the lottery was drawn on 28 January 1805, but lived long enough to see each of the 22,000 tickets purchased at three guineas apiece (£270 each in modern terms).  To encourage ticket sales and reduce unsold inventory, every purchaser was guaranteed to receive a print worth one guinea from the Boydell company's stock.  There were 64 winning tickets for major prizes, the highest being the Gallery itself and its collection of paintings.  This went to William Tassie, a gem engraver and cameo modeller, of Leicester Fields (now Leicester Square).  Josiah offered to buy the gallery and its paintings back from Tassie for £10,000 (worth about £800,000 now), but Tassie refused and auctioned the paintings at Christie's.  The painting collection and two reliefs by Anne Damer fetched a total of £6,181 18s. 6d.  The Banks sculpture group from the façade was initially intended to be kept as a monument for Boydell's tomb. Instead, it remained part of the façade of the building in its new guise as the British Institution until the building was torn down in 1868–69. The Banks sculpture was then moved to Stratford-upon-Avon and re-erected in New Place Garden between June and November 1870. The lottery saved Josiah from bankruptcy and earned him £45,000, enabling him to begin business again as a printer.
What is the first name of the person who auctioned the paintings at Christie's?