Take The Gilded Age. Farewell to Fifth Avenue and Mrs. Astor's Horse -- blend them with a bit less vinegar and pepper, a little more sauce of social conscience, a base of historical awareness and you'll have some idea of The Saga of American Society. It has the spice with less of malice; it has the human interest and the society column appeal with better focus; it has the verve and humor and wit that gave the other books their popularity. But it is not cheap. It is a definite contribution to our national social history. And it is a fairly definitive piece of historical and biographical research into the sources of our lares and penates. Grand reading and certain of a good press.