STOCKHOLM.- At Bukowskis autumn auction last year, Nationalmuseum acquired one of Johan Tobias Sergels few remaining clay models from a series of royal portraits, a bust that has been in private ownership until now. The portrait of the 21 year-old Duchess Hedvig Elisabet Charlotta has a freshness and immediacy, with clear traces of the sculptor at work. When Johan Tobias Sergel was recalled to Sweden from Rome by King Gustav III, the sculptor hoped to be able to continue working on major themes from the ancient myths of gods and heroes. However, it perhaps came as no surprise to him that his future output in Sweden would take on a very different character. After all, the King had commissioned a portrait of himself just before Sergel left Rome on Midsummers Eve 1778. As soon as the sculptor arrived home, he had to quickly get started on his depiction of Gustav III, which was intended as a Christmas pres