Arts: The Hermitage Treasures: I

FOR decades art experts around the world have yearned to get through the Iron Curtain and see for themselves what is on the walls of Leningrad's famed, sprawling, be jeweled Hermitage Museum. Those who have been able to do so in the post-Stalin thaw have come away with confirmation of a long-held belief: the Hermitage is every bit as good as the Communists claim (see color pages for some of its rarely reproduced masterpieces). Sterling Callisen, the Metropolitan Museum's dean of education, who recently spent six goggle-eyed, footsore days roaming the Hermitage's 15-odd...