- Historic Sites
The Case Of The Vanishing Records
August 1969 | Volume 20, Issue 5
The hard facts were there for librarians to see. When skeptics said that the volumes were still on the shelves and that the terms that the librarians were using, such as “disappearing books,” were exaggerated, the rejoinders were quick in coming. Gordon Williams, director of the Center for Research Libraries in Chicago, a collection of some two and a half million volumes used for advanced research by thirty-nine universities from Harvard to the University of California, made the point quite clear.
You ask what is meant by a book that is “disappearing.” This is one the paper of which has now become so brittle that you cannot handle the book, or turn the pages, without the paper breaking and crumbling. Such a book is essentially unusable. If the pages are not already too broken to use, the next person to read it would destroy it.
In seeking the cause of the problem, Barrow looked first at the wood base of the paper, for the appearance of short-lived paper seemed to coincide with the change-over from rag to wood pulp. There was no doubt that this was the cause of the disintegration of groundwood newsprint. Chemically, groundwood papers are half cellulose and half non-cellulose, and after fifteen to twenty years the non-cellulose materials break down into acid compounds and eat themselves up.
But what about the high-quality chemical-wood papers and the rag papers made since 1870? What was causing them to disintegrate? Here the answer was a surprise. Barrow took a hard look at the sizing used in papermaking. All papers made for writing and printing are “sized,” a term which comes from Old French and means “to set” or “to fix.” Sizing is quite simply a substance that is added to paper to prevent the ink from being absorbed and thus feathering over the surface. (A blotter is an example of unsized paper.) Until the second quarter of the seventeenth century, the sizing agent generally used was gelatin or glue made from the hides and tendons of animals. This is what helped produce the mildly alkaline, long-lasting paper of the time of Abbot Tritheim. But in the second quarter of the seventeenth century, alum began to be added to the gelatin to make the paper more resistant to ink. Alum is aluminum sulfate and is highly acid. Since papers manufactured after the second quarter of the seventeenth century tended to disintegrate faster than those made earlier, Barrow thought that he had spotted the cause.
The next critical test era was the 1850*5, when a new method of sizing, which did away entirely with animal gelatins and glues and replaced them with rosin, came into general use in the United States. This new alum-rosin sizing could be more easily applied than the gelatins and glues, and so was quickly taken up by paper manufacturers anxious to increase their output. Barrow made a thorough study of this alum-rosin sizing. It was known that alum by itself was acidic, but an investigation of the new sizing revealed something extraordinary. When the alum combined with the sodium resinate of the rosin, the resulting mixture decomposed into components of sulphuric acid that could burn up a book in thirty years.
To study the effect of this alum-rosin combination, Barrow tested five hundred nineteenth-century books, fifty published in each decade, and divided these up into three broad groups, those of 1800 to 1849, those of 1850 to 1869 (when alum-rosin sizing was first being introduced), and those of 1870 to 1899, when the new sizing became almost universal in papermaking. Even though some of the books of the second period were printed on paper made of the same material as those of the first—linen and cotton rags—they were in much poorer condition than those in the first period. The books from the last period were the weakest of all. Though there was no question but that the use of wood fibers that had not been thoroughly washed and the use of short fibers in the chemical-wood papers contributed to the weakness of the books published since 1870, the main culprit in the destruction of most paper was the sizing. Barrow stated the fact baldly: “The introduction of alum-rosin size contributed more to the deterioration of paper than any other development in papermaking.” Thus rag paper sized with alum-rosin was not really much better than wood paper.
In the ten years that have passed since Barrow made his report, the full impact of the highly acidic alum-rosin-sized paper has hit libraries and the scholarly community. Frazer G. Poole, the assistant director for preservation at the Library of Congress, says “It is undoubtedly one of the most serious problems in the library world.” In a collection as large as that of the Library of Congress many books are used infrequently but must be preserved for those times when they are needed by scholars. It is impossible for the Library to keep a check on all the books on the shelves, and Mr. Poole admits that it is nearly impossible to predict which books will “disappear.” “We will know that answer in a hundred years,” he warns, “and then it will be too late.”