THERE CAN'T BE MANY PEOPLE TOday who would think of putting Jean-Baptiste-Camille Corot (1796-1875) among the giants of 19th century French painting--Delacroix, Courbet, Manet, Monet or Cezanne. Yet in his lifetime he was regarded as one of the greatest landscapists who ever lived, and for most cultivated Frenchmen the very idea of comparing a bungler like Cezanne with their beloved Corot would have seemed faintly barbarous. The big show that opened in Paris last month--drawings and prints at the Bibliotheque Nationale, 163 paintings at the Grand Palais--marking the 200th anniversary of Corot's birth, is unlikely to bring that feeling back. (It...

