Precious paper

In the sunny, old-fashioned laboratory of what was once a private girls' school, T.K. McClintock pored over an aged, yellowing document. On close inspection, it turned out to be an 1823 copy of the Declaration of Independence. Mr. McClintock appeared to be washing it.

Washing is not what you'd ordinarily do to precious papers. But McClintock was not giving the document the Clorox test. As art-on-paper conservator at the Northeast Document Conservation Center in Andover, Mass., he was gently bathing the document to remove acids and grime that build up over the years and eventually destroy untreated papers.

According to Ann Russell, director of the center, ''Increased air pollution and the declining quality of paper are causing our historic records, books, and documents to deteriorate at an ever-increasing rate. Our cultural heritage is literally crumbling away.''

Indeed, the Library of Congress estimates that one-third of its books are too brittle to be handled.

Surprisingly, old books often last longer than new. Sixteenth-century rag-paper books, for example, have endured remarkably well. But paperbacks printed on wood pulp paper only 10 years ago are turning yellow at the edges, says Dr. Russell.

The self-destructive-paper problem is a price we pay for the mass production of books. After the 1860s, publishers began to use wood pulp to make paper. It was cheaper and more plentiful than rags. The trouble with wood-pulp paper, explains Mary Todd Glaser, senior conservator of the center, is that its lignin (the glue that holds the wood fibers together) turns dark easily. And the water in the paper, plus the alum added to prevent ink from ''feathering,'' combine with sulfur dioxide in the air to form sulfuric acid.

''Acid is paper's biggest enemy,'' Ms. Glaser said. ''It's almost everywhere. The acid attacks the paper fibers and shortens them, eventually turning them into sawdust.''

Museums and libraries exist to preserve historic books, documents, and fine art works. But the problem of paper decay is now so vast that this legacy is being destroyed faster than it can be saved.

The problem is threefold, according to Dr. Russell. First, for many collections, the relatively unglamorous task of preserving assets receives a low budget priority. Second, few institutions can afford their own conservation equipment. And third, even if they could, there are not enough trained conservators to fill the jobs created by in-house laboratories.

There are only about 50 certified paper conservators in the country. The nation's three art conservation schools graduate only 10 students apiece each year, and the only book conservation program in the United States, at Columbia University, has yet to award its first diploma.

Centers like the Northeast Document Conservation Center (NEDCC) provide a cost-effective solution to this problem. NEDCC is a regional cooperative enterprise offering conservation services to nonprofit museums, libraries, and archival collections in the Northeast.

Founded in 1973 by the New England Library Board, NEDCC is one of a network of regional conservation centers that have sprouted across the country. The National Conservation Advisory Council calls them the ''newest type of treatment facility.'' The cooperative centers are financially independent nonprofit organizations operating through a combination of grants and fees. Some are housed on the site of a museum; others have their own buildings. The Northeast Center is located in the Victorian red-brick Abbot School, a now-defunct academy that pioneered science education for girls - hence the spacious laboratories.

Because they respond to the needs of their area, the cooperative centers tend to specialize. The Pacific Regional Conservation Center in Honolulu, for example , has facilities to treat the ethnographic objects of the Pacific. New York State has set up a regional center at Peebles Island for its 34 state historic sites. Philadelphia's Conservation Center for Art and Historical Artifacts specializes in watercolor restoration.

Museum-rich Massachusetts actually has two other conservation centers besides NEDCC. The Williamstown Regional Art Center at the Clark Art Institute treats paintings and art works on paper for about 20 member museums. The Fogg Art Museum in Cambridge houses the oldest ''regional'' center for conservation. Established in the 1930s, the Center for Conservation and Technical Studies treats fine art works and is a research laboratory and training center for students at Harvard.

Most of the centers started operating with government seed money and many continue to run with the help of private and public grants. But today fees for service are the mainstay of the centers' operating budgets, in NEDCC's case making it virtually self-supporting. According to Ann Russell, of an operating budget slightly in excess of $600,000, $500,000 of that comes from work performed.

At NEDCC, field service director Mildred O'Connell surveys libraries and museums to provide each with a long-range preservation plan. Because of the density in the area, Ms. O'Connell selects carefully the 50 institutions she surveys each year.

Trained as a specialist in architectural preservation, Ms. O'Connell advises her clients on such questions as storage design, including temperature control for books and art materials. She might advise, for example, moving boxes of material out from under water pipes.

''I'm always amazed,'' she said, ''at the wonderful wealth of material small libraries and historical societies have here in the Northeast. Often it is stored in the attic or basement, literally collecting dust.''

Recently, director O'Connell surveyed the Newark (N.J.) Public Library. There , budget cuts have slashed operating budgets and staff by one-third. Without an air-conditioning system that could cost less than $1,000, the library's valuable special collection and what librarian Stephen Crook calls ''one of the finest art-on-paper collections in the country'' are ''turning into cornflakes.''

''The library is reduced,'' said Mr. Crook, to ''nickel-and-dime preservation techniques.'' Last summer, to ventilate the collection in the turn-of-the-century building, librarians could only open windows, thus billowing in dust and debris from construction next door.

Libraries and museums, faced with tightening budgets, must choose wisely what they must preserve. But for NEDCC and other conservation centers, the magnitude of the paper-decay problem means that for now there is no shortage of work.

NEDCC's busy laboratories wash, de-acidify, and repair antique documents, prints, drawings, and even wallpaper. Its three bookbinders take apart a book page by page, de-acidify each, and resew the binding by hand. NEDCC's microfilm department records precious materials that might otherwise be available only to a handful of scholars. The center has a photograph restoration service and mans a free disaster hotline for organizations confronting flood, fire, or skunks in the basement. (Mildred O'Connell advises flash freezing of sodden papers to prevent mold growth - then each piece can be dried at leisure).

NEDCC will treat any work on paper but specializes in written documents. Mr. McClintock, one of NEDCC's 12 conservators, said that he had different goals when treating fine art works and archival materials.

''The fine art works are one-of-a-kind creations as a rule, in which the artist's intention must be preserved,'' he said. ''On the other hand, for archival documents, legibility is the most important thing.

''Among the documents NEDCC has preserved are manuscripts by Ernest Hemingway , survey maps by Henry David Thoreau, John F. Kennedy's report card, a print by Winslow Homer, and the Salem witch trial papers.

McClintock, who was trained in conservation techniques at Cooperstown, N.Y., demonstrated how conservators must combine a knowledge of chemistry with fine arts.

''We begin by examining the item carefully and surface clean it with an eraser powder,'' he explained.

''We then test it for solubility. If it's OK, we wash the document in filtered water and immerse it in magnesium bicarbonate, an alkaline solution.''

The conservator picked up the Chagall chromolithograph he was working on and said, ''This lithograph is not in poor physical condition, but it has been stained by its frame and by exposure to light.''

McClintock explained that he would bleach the darkened area very carefully, then de-acidify it and reframe the picture.

Intern Mimi Batchelder showed how she preserved an 1863 officer's commission signed by Abraham Lincoln. She removed the vellum sheet from its cardboard backing, humidified it to relax the fibers, then pressed it between blotters to take the moisture out. Finally, she encapsulated it between sheets of mylar and mounted it on backboard.

Hanging within easy reach of each conservator's work space are strips of Japanese mulberry bark paper. These are used, McClintock said, to fill holes in documents. The strips are attached with wheat paste. Often, a whole document will be remounted on the durable nonacidic paper. When a document is peppered with holes, the laboratory's Israeli-built leaf-casting machine plugs them with soggy paper that expands to fill the gaps.

The nature of conservation work makes it very labor intensive. Nowhere is this more obvious than in the book bindery.

Sherelyn Ogden, who heads the book bindery, notes that with older books (early Western European printed books, for example) no treatment is often best. The book is simply enclosed in a simple but acid-free box.

''Where the artifact value is not so critical, however,'' she explained, ''we carefully remove the spine of the book, dye new leather to match the old, and put the original spine over the new leather, using rice starch paste adhesive.''

The center emulates the binding on early books, which is much more durable than machine-made binding. NEDCC's bookbinders sew pages by hand onto raised cords; then they lace the covers onto the pages with cord worked into the cover board itself.

Each book, explains Ms. Ogden, takes about 15 to 18 hours to bind. If the ''full treatment'' is ordered - that is, if each page is washed and de-acidified - the procedure takes 50 hours and costs several hundred dollars.

A method to de-acidify books en masse is simply not available at the moment. However, NEDCC is taking part in the first large-scale de-acidification experiment to be conducted by the US Library of Congress. At the center an atlas was cut in four pieces. Conservators sent one piece to the Library of Congress, another to the Public Archives of Canada, which is running its own de-acidification experiment, and kept two at the Northeast Document Conservation Center as controls.

The Library of Congress borrowed a NASA vacuum chamber - used to simulate space conditions - for the experiment, in which 5,000 books, including NEDCC's atlas, were ''gassed'' with diethyl zinc vapor. The library's own preservation scientists patented the DEZ process. The gas neutralizes acid and leaves a harmless zinc carbonate residue that is expected to increase a book's lifespan four times. The books came out of the vacuum chamber just a few weeks ago.

''So far,'' says Imre Jarmy, the Library of Congress national preservation program coordinator, ''everything looks as it should.'' He cautioned that it would take librarians two to three months to analyze each page for acid content.

If the experiment is successful, Mr. Jarmy said, the library would construct its own treatment facility within the next 18 months. Such a chamber would cost treatment would be reduced to about $5 per volume.

Jarmy doesn't see other libraries or cooperative conservation centers building their own vacuum chambers, however, despite the extent of paper decay. Apart from the cost, the gas is highly dangerous. It explodes when it comes in contact with water and catches fire when exposed to the atmosphere. If a vacuum chamber were built, the Library of Congress would presumably become a clearing house for book de-acidification - if it ever got beyond its own collection of 20 million books.

In the meantime, the National Conservation Advisory Council notes in its publication, Conservation Treatment Facilities in the United States, that curators and archivists might do better to slow acquisition and spend their scarce funds in taking care of what they already have.

As T.K. McClintock said, lifting his head from his Declaration of Independence, ''We're not trying to make anything look brand new. We just feel that keepers of cultural patrimony have a responsibility to pass on the material in as good condition as possible.''