Table of Contents  Papyri  Incunabula  Paper, Parchment & Vellum  Books & Book Covers: Rigid and Flexible – Parchment, Vellum &Fabric

Papyri Collection  Papyrus is a thick paper-like material produced from the pith of the papyrus plant, Cyperus papyrus (papyrus sedge or paper reed) which was abundant in the Nile Delta area of Egypt.  Papyrus is first known to have been made and used in ancient Egypt as far back as the third millennium BC. It was also used throughout the Mediterranean region.  Yale Papyrus Collection began in 1889 and numbers over six thousand inventoried items that are cataloged, digitally scanned, and accessible online for close study. 

Incunabula Incunabula is a generic term coined by English book collectors in the seventeenth century to describe the first books, pamphlets, and broadsides that were printed - not handwritten - before the year 1501 A.D. The term is formed of two Latin words meaning literally "in the cradle”. One of the world's major repositories for books printed in the fifteenth century, the Beinecke Library has over 3100 incunabula, with approximately 425 elsewhere at Yale. Highlights of the collection are the Melk copy of the Gutenberg Bible, as well as the 200 titles in the Edwin J. Beinecke Memorial Collection. Holdings are strong in Greek and Latin classics, Italian humanist literature, historical texts, biblical literature and exegesis, and Hebrew printing. More recent areas of concentration are secular vernacular texts, illustrated books, and works by fifteenth-century authors. Copies in early bindings, notably a large group in German monastic bindings, or with evidence of early readership or provenance are prominent in the collection and in current collecting. Rare presses or typographically significant or innovative volumes document the history and spread of printing. Holdings are strongest in Italian, German, and French imprints, but English and Spanish presses are well represented. Records for these can be found in Orbis, the Yale University Library’s online catalogue. To browse, follow the directions on Yale’s Library Help Page.

Background Information: Paper, Parchment & Vellum  There are a variety of plants that can serve as sources of cellulose for paper-making, which include linen, cotton, hemp, and mulberry.  Prior to the 19th century paper was made by hand. Most paper consisted of cotton, hemp, linen or mulberry fibers and are commonly referred to as rag paper. Rag papers are quite durable and can be preserved for hundreds of years.  With the onset of the modern paper industry in the early 19th century, wood-based papers became an abundant and inexpensive alternative to costly rag papers. As with many inexpensive materials, cost efficiency did not coincide with durability.  Wood-based papers are prone to degradation due to the presence of the chemical compound lignin. Lignin forms acidic compounds if it is not removed during the paper making process. The presence of these acids causes the paper to degrade becoming yellow and brittle, eventually leading to total disintegration.  Parchment and vellum are made from the skins of small animals. Traditionally, the skins are treated with slaked lime which acts as a preservative. The skin is then rubbed smooth with an abrasive such as chalk or pumice. Generally, parchment refers to the skin of sheep and goats, while vellum refers to finer quality skins of calves, kid or lambs. ** Above information from: The Care and Preservation of Archival Materials by Mary Fahey, Head of Preservation/Chief Conservator, The Henry Ford **

Background Information: Books & Book Covers BOOKS - Three Basic Components (1) pages or leaves consisting of parchment or paper (2) a protective covering made from leather, parchment or fabric (3) the media that has been used to create the document BOOK COVERS - Rigid and Flexible Both flexible and rigid book covers made parchment, vellum and fabric have been used over the years. For rigid covers - cardboard, pasteboard and wood have been used as the underlying support. Pasteboard is a rigid material that is made by lamination of leather and parchment scraps. Leather has been used for the manufacture of book covers since medieval times, made from a variety of animals as cattle, pigs, deer and sheep. For the majority of book coverings, tanned leather was utilized. Tanning is a process by which leather is chemically treated in order to impart strength and stability. A variety of tanning processes have been developed over the years and each varies in its effect upon the longevity of the leather.  Leather that was produced prior to the 17th century using a vegetable-tanning process has proven to be highly stable.  During the mid-1800's, an increased demand for leather goods led to the development of a variety of new processes which vary in stability.  Much of the vegetable-tanned leather that was produced during the 19th century is especially unstable and prone to the development of Red rot. Red rot appears as powdery red degradation that is caused by the presence of sulfuric acid in the leather. ** Above information from: The Care and Preservation of Archival Materials by Mary Fahey, Head of Preservation/Chief Conservator, The Henry Ford **

Background Information: Book Covers continued... PARCHMENT AND VELLUM Parchment and vellum were widely used for written materials up until the 19th century. Like leather, parchment and vellum are manufactured from animal skins. Both materials are strong and durable but are highly sensitive to moisture changes. Parchment and vellum undergo dramatic expansion and contraction corresponding to absorption and evaporation of water which leads to the formation of wrinkles and puckers. When utilized as coverings over wood or cardboard, this instability can lead to warping and distortion of book covers. FABRIC In recent times, the use of fabric and paper has increasingly replaced leather as book covers. Sized linen or cotton fabric is frequently used. Sizing refers to the application of adhesive such as gelatin, plant gums and starches to the surface of a sheet of paper. It is added to make the surface less absorbent in order to prevent the bleeding of ink and other printing media. Bookcloths, first manufactured in England in the early 1820's, were sized with starch which imparted rigidity and resistance to water damage. In 1910, pyroxylin-treated fabrics came into use but were found to be unstable. Acrylic materials are becoming a common replacement for the traditional starch-based sizing. Other fabrics that have been used as cloth covers include silk and velvet. ** Above information from: The Care and Preservation of Archival Materials by Mary Fahey, Head of Preservation/Chief Conservator, The Henry Ford **