After fire in 1697, when Tessin planned the new palace, the Royal Chapel and the Hall of State were placed in the southern row and these, including the grand stairs, occupies the first and second floor. The chapel represented the divine power and the hall the worldly, or the king's, power. After Tessin's death, his work was completed by Carl Hårleman. The church was inaugurated at the same time as the rest of the palace in 1754. The Hall of State is in the west half of the southern row of the palace and is two stories high (first and second floor). It was introduced for the Riksdag of 1755. The hall was designed by Hårleman who modified Tessin's plans. The Silver Throne of Queen Christina is placed in the Hall. The main entrance of the Hall is in the South Portal (or Arch). In the cellar of the southern row is the Treasury, where the Regalia of Sweden are displayed. The museum was inaugurated in 1970. The Chancery Wing is another name for the northwest wing of the palace. It was planned for the central parts of the government administration, the Royal chancery. The wing was finished by architect Carl Fredrik Adelcrantz, and was originally used as the royal gardhouse, offices for domestic, foreign and war departments as well as the National Archives of Sweden. As the government administration grew, it moved from the palace and formed new independent departments, and around 1780, the Chancery Wing was transformed into an apartment for the three-year-old Crown Prince Gustav (IV) Adolf and later for his mother the Queen Dowager Sophia Magdalena. The Chancery Wing was once again the home of a prince in 1905, when it became the Crown Prince and later King Gustaf VI Adolf, who used it as his private lodgings until his death in 1973. A part of the mezzanine floor above his apartment was converted into his private library in the 1930s. The "Spegelsalongen" (the Mirror Hall), updated in 1866 by Fredrik Wilhelm Scholander, is in the wing as well as a Green and a Blue Drawing room. The Slottsarkivet, a part of the present National Archives of Sweden, is still in the cellars of the wing. The second oldest museum in Sweden is Gustav III's Museum of Antiquities in the cellars of the northeast wing, which open up for the public in 1794.