Stopping decay of nation's books

IN a windowless conference room deep in the bowels of the Library of Congress, Peter Sparks shows how the largest collection of books in the world is self-destructing. He picks up a tattered volume published in the 1890s (``Sartor Resartus: The Life and Opinions of Herr Teufelsdroockh,'' undoubtedly a big hit back then). The pages, yellowed and fragmented, crumble when he tries to bend them.

``All of our books, save a very few, are headed in this direction,'' says Dr. Sparks, a chemist and the library's chief of preservation.

The main culprit: the acidic paper used to produce most books since the mid-19th century.

Low-grade acidic paper can deteriorate into a brittle mess in as little as 25 years. Moisture and pollution in the air add to the problem. Eventually, the contents of brittle books must be transferred to microfilm or be lost. Techniques for preserving books exist, but they are too time-consuming and expensive to be applied on a large scale to general-circulation books.

That could change, however, with new technology that permits the mass de-acidification of thousands of books at a time. The method, pioneered by the Library of Congress, is expected to cost less than $5 a book and will reportedly add 500 years to the life of a volume.

Microfilming a book, by contrast, costs between $45 and $70 and usually means the loss of the book in its original form.

The library estimates that 77,000 of its books move from the ``endangered'' to the ``brittle'' category every year. One in 4 of the books in the library's general and law collections is now too brittle to use. Studies conducted at the New York Public Library, Stanford University, and Yale University show similar levels of decay.

``What we're facing is the `Silent Spring' of scholarship with this brittle-book problem,'' says Merrily Smith, a national preservation program specialist at the Library of Congress.

Indeed, the problem is a global concern. Research into mass de-acidification is being conducted by the Biblioth`eque Nationale in Sable, France, and a de-acidification program is already under way at the Public Archives of Canada in Ottawa. Similar work is being done in Austria (primarily with newspapers) and could soon begin in Japan.

Before the last century, most paper was made from cotton or linen rags and was naturally low in acid. Widespread literacy, however, brought with it the demand for a cheaper and more plentiful source of paper for newspapers and books. The industry then began using chemically treated wood pulp.

It is the chemicals used in this paper, especially the aluminum sulfate used to prevent the ink from running, which has led to today's problem. Aluminum sulfate eventually combines with moisture in the paper to form sulfuric acid, which then begins breaking down the cellulose fibers in the paper. The result: crumbling pages.

A small but growing number of American publishers are using acid-free paper. Foreign publishers, however, have made very little effort to change over. Since more than 50 percent of the Library of Congress's holdings are published abroad, the effort to develop large-scale de-acidification has been given high priority here.

Oddly, the books most in danger of being lost are not the rare literary treasures you might expect. The Library of Congress's Gutenberg Bible, which was printed five centuries ago on thin calfskin treated to hold ink (vellum), is in remarkably good shape.

Observers agree that what makes mass de-acidification significant is that -- for the first time -- books that do not merit special attention as a rare item but that still constitute part of intellectual history can be preserved easily and cheaply in their original form.

The library's technique involves putting books inside an airtight chamber and pumping in diethyl zinc gas, an acid neutralizing substance. Molecules of diethyl zinc are so tiny -- 2 million of them could be strung across the head of a pin -- that they make their way easily between and through the pages of a book. The gas neutralizes all the existing acids in the paper while also reacting with water present in the paper to form zinc oxide. The zinc oxide serves as an alkaline reserve to neutralize any future acid that might form in the paper.

The first experiments, conducted in the 1970s, used a pressure cooker in the library's laboratory and de-acidified only a few books at a time.

In late 1982, the library sent 5,000 books to the National Aeronautics and Space Administration's research facilities at the Goddard Space Flight Center outside Washington, D.C. There, a large vacuum chamber once used to simulate intense solar radiation was adapted for a scaled-up de-acidification experiment that lasted 13 days.

The library is planning an $11.5 million facility at Fort Detrick, Md., which will treat books in batches of 15,000 starting in 1990. It will take about a week for a batch to be processed. The facility's immediate mission will be to de-acidify the library's book collections.

Sparks estimates the job will take at least 20 years. The library has more than 81 million items stretched out over 535 miles of shelves. ``We'll get the new stuff as it moves through the door, while preserving everything that we can which is endangered.'' Since the treatment can't help books that are already brittle, priority will be given to those classified by the library as ``endangered.''

The development has wide-ranging implications. Although the Library of Congress will initially treat only its own books and perhaps some from other federal agencies, groups of libraries around the United States are said to be interested in banding together to build facilities based on the technology.

Sparks has had inquiries from groups in Illinois and Ohio. The library plans to license the technology free of charge, leaving the actual commercialization to private interests.