Last week’s London art sales signalled a shift in taste in the art markets, writes Carol Vogel. “Buyers’ appetites consistently moved from the 19th century toward classic modern and contemporary art. Prices soared for 20th-century masters like Egon Schiele, Jean-Michel Basquiat and Francis Bacon, while pretty, Impressionist canvases by household names like Renoir or Monet either didn’t sell or brought lower prices than auction house experts had predicted.”