![]() Alum, which is used in some papermaking processes and as alum–rosin sizing to impart specific characteristics to paper, may break down to yield sulfuric acid. Although pure cellulose papers – such as linen or cotton rag papers – are generally stable, cellulose can become acidic via oxidative and hydrolytic processes forming bound acids (through conversion of pendant hydroxyl groups), as well as volatile species such as acetic and formic acid. What causes acid degradation?Īcidity principally arises from the degradation of cellulose and lignin, and the presence of alum. One of the most significant challenges to the longevity of paper is acidic degradation, a problem that has been recognised since the early 19th century. However, without conservation and careful handling, paper does not last. From illuminated medieval manuscripts and historical documents to some of the earliest writings ever recorded, the bulk of material held in most collections is made of paper. Use weights to hold down pages, but place them round the edge, rather than on top of the printed or drawn image.Libraries and archive collections are an unparalleled resource for our history and culture, containing the wealth of human knowledge and artistic expression. Make sure that you have enough space before unrolling a large document. These may be stored flat, rolled or folded. There are many different types of large-scale document, including maps, plans, blueprints and posters. Use weights to hold down pages, and use a paper marker to follow the text. Use a foam pad for additional support at the beginning and end of the book. This puts less strain on the spine and creates a comfortable reading angle. Use wedges to support the book at an angle. Many different styles of binding are to be found at The National Archives, from limp vellum bindings, to library bindings and account bindings.Īsk staff for help if a book is particularly large or heavy, or if pages are stuck together. When scrolling through the document, re-roll it as it is read. When turning the document over, be sure to turn the seal at the same time. If a pendant wax seal is attached to the document, ensure that the seal is resting on a foam pad. Use a paper marker to follow the text instead of fingers. Use weights to hold the parchment in place. This means that the text is particularly vulnerable to inappropriate handling. Parchment is made from animal skin so does not absorb ink like paper does. These may be bound volumes, documents with wax seals, or large rolls made from several sheets of parchment sewn end-to-end. Many of the early records, including treaties, charters and wills, are made of parchment. Tuck the pages inside the cover so that they are protected. Please ask for assistance if the file is damaged or badly tagged. The punched hole is particularly vulnerable and easily torn. If the tag is not long enough, please take the document to a member of staff who will retag it for you. The tag should be long enough so that you can turn the pages when the file is fully open. The type of paper and the page size may vary, and files may contain photographs, or folded maps and drawings. Handling filesįiles consist of loose sheets held together in one corner by a treasury tag. ![]() If you are having problems with a particular document – for example, if it is very heavy or too fragile –please contact a member of staff.įind out more about preservation at The National Archives. Preservation aids are available at clearly marked locations throughout the reading rooms. use the preservation aids provided to ensure that documents are fully supported.ensure you are not holding them while reading and make sure they do not hang off the edge of your desk while reading.attempt to re-file the items in your preferred order.remove individual items from files, volumes or boxes.Please keep the documents in the order in which you received them. use powder-free nitrile gloves when handling photographs, and hold them by the edges (the only exception to our gloves rule – the natural oils in skin can damage the surface of photographs).avoid leaning on or touching the document, use a paper marker to follow the text. ![]() do not lick your fingers when turning pages.wash your hands before you start working and avoid using hand cream and hand sanitiser in the reading rooms.There are some general practices that should be followed by everyone: All visitors to the reading rooms are asked to wash their hands before and after their visit. We do not allow gloves to be worn in our reading rooms, in line with long-standing guidance relating to the preservation of our collection. Everyone visiting The National Archives has a responsibility to preserve the documents in our care. ![]()
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