SANTIAGO, Chile — During the darkest years of this country's military dictatorship, Mariana Callejas was an up-and-coming writer and the hostess of the era's most glamorous literary salon. Chile's leading authors trekked up to Callejas' hillside mansion every Thursday night to talk literature, have a few drinks and sometimes dance until the next morning. The salon offered a respite from the fear and violence of Gen. Augusto Pinochet's Chile, in which nearly 3,200 dissidents died or disappeared at the hands of government agents. Writer Carlos Iturra, who attended the meetings, said in an e-mail that he'd always remember those nights for "the good writers who were formed there" amid the "dances, drinks, laughs and debates." Horror lay just below the glittering surface, however, as it often did during the 1973-90 military dictatorship.