Repairing Parchment

Parchment is a very durable material and even if it is quite sensitive to humidity (see previous post) it can withstand a lot of wear and tear. This characteristic has made it a favoured writing material for several thousand years. It replaced papyrus when the first multi-quire codices came into use because its flexibility and resilience allowed the centrefold of the several gatherings to be sewn together into text blocks without tearing1; and when paper became the most widespread writing and printing support, parchment still continued to play an important role in bookbinding as a covering material.

Nevertheless parchment can be damaged when documents are heavily used or misused. Tears, splitting and losses can result (figs. 1 and 2).

Figures 1 and 2 – The Book of Mulling with repaired damaged areas, TCD MS 60, ff. 1r, 6r © The Board of Trinity College Dublin, the University of Dublin. 2015.
Figures 1 and 2 – The Book of Mulling with repaired damaged areas, TCD MS 60, ff. 1r (left), 6r (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.

Repairing parchment has therefore been a necessity for many centuries. In earlier times when damage occurred along the outer edges of a document or page it was not uncommon to trim the sheet. When damage occurred within the body of the folio, different techniques to patch losses were applied including patching the damage with an additional piece of parchment or paper adhered with glue or paste.

Stitching was a more refined way to repair parchment and one that avoided obscuring the text in the treated area. This technique followed the tradition of parchment makers who would mend holes on the fresh skins with sewing threads, joining the edges of damaged areas while the skin was still on the stretching frame, and using the collagen released during the scraping process as an adhesive to further consolidate the repair.

On our manuscripts we can find an interesting array of repair techniques used during their long history (see previous post – book moth). The Book of Mulling and Codex Usserianus Primus (see previous post) have both been extensively repaired. For both of them “grangerisation” (see previous post) was carried out in the 19th century. This resulted in individual pages of the manuscripts being inlaid into paper sheets to enable rebinding. Tears and losses along the margins were mended with strips of paper (fig. 3 and 4).

Figures 3 and 4 Codex Usserianus Primus still inlaid in paper and with paper repairs obscuring part of the text, TCD MS 55, ff. 163v (left), 182v (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.
Figures 3 and 4 Codex Usserianus Primus still inlaid in paper and with paper repairs obscuring part of the text, TCD MS 55, ff. 163v (left), 182v (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.

In more recent times the Book of Mulling was further conserved. New spine folds were created and the losses along the margins infilled to create a compact and uniform text block for rebinding. For this treatment new parchment was chosen. The repair patches were selected according to the thickness of the original skin, shaped to match the profile of the missing area and adhered. To obtain a secure attachment between the old and the new parchment in some areas a relatively large overlapping of the two was necessary.

Mulling f. 34 with corner detail
Figures 5a and 5b The Book of Mulling with detail of the head corner and edge with the adhered toned parchment repairs made in the 1970s, TCD MS 60, f. 34v © The Board of Trinity College Dublin, the University of Dublin. 2015.

Some of our most important early manuscripts including the Book of Kells and the Book of Dimma were conserved between the 1950’s and the early 1980’s by Roger Powell, regarded as one of the most skilled manuscripts conservator of the times. He developed and used an improved method of executing repairs, by combining the adhesive technique with the old sewing practice and thus creating a functional and durable solution. This sewn repair was very effective because the strength of the parchment allowed fine stitches to be used without risk of tearing.

Figures 6 and 7 The Book of Dimma with the repairs sewn by R. Powell (1957), TCD MS 59, f. 148 (left), 147 (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.
Figures 6 and 7 The Book of Dimma with the repairs sewn by R. Powell (1957), TCD MS 59, f. 148 (left), 147 (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.

In figures 6 and 7 two different stitching patterns can be seen. In fig 6 the stitching is securing an adhered parchment in-fill while in fig 7 the stitching is used to pull together the edges of the manuscript and the patch without overlapping the text.

A development of this technique involved the use of a thin parchment strip passed through slits in the parchment, instead of the linen thread passing through holes, which further reduced the risk of tearing of the original (figs. 8 and 9).

Figures 8 and 9 Book of Mulling showing the sewn repair using a fine parchment strip instead of a linen thread. TCD MS 60, f. 94r (left), f. 94v (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.
Figures 8 and 9 Book of Mulling showing the sewn repair using a fine parchment strip instead of a linen thread. TCD MS 60, f. 94r (left), f. 94v (right) © The Board of Trinity College Dublin, the University of Dublin. 2015.

Powell’s treatments are still regarded as high achievements in the field, however today a less invasive approach is taken. For the Garland of Howth, the Book of Mulling and the Codex Usserianus Primus a thin protein-based film called caecum has been used.

Caecum, named after the part of intestine from which it is extracted, is the modern version of the traditional gold beaters’ skin (or swim bladder) which has often been used to repair parchment. Caecum is an extremely refined material, similar in nature to the parchment and therefore compatible with our manuscript folios. Because of its thinness it is challenging to handle the tiny sections required for tear repairs, so it is supported with a facing of very thin Japanese tissue adhered with an acrylic adhesive.

Marco repairing Ussherianus Primus

Figures 10 and 11 Applying a small patch of caecum on a split of TCD MS 55 with stainless tweezers and setting it with a Teflon folder.
Figures 10 and 11 Applying a small patch of caecum on a split of TCD MS 55 with stainless tweezers and setting it with a Teflon folder.

Working under magnification the paper-faced caecum is cut to the size and shape of the repair and adhered to the parchment with a low temperature pure fish gelatin. Once the repair is dry a tiny amount of solvent is applied with a thin brush to soften the acrylic adhesive and remove the facing paper, leaving a strong and almost invisible repair.

Figures 12a and 12b Codex Usserianus Primus, TCD MS 55, f. 135v, top right corner, showing several splits on the parchment due to the heavy ruling on a very thin skin. On the left is a detail during conservation with the caecum applied but still with the tissue facing on it; on the right the same area after conservation with the caecum holding the splits and the fragment inserted in its conservation mount © The Board of Trinity College Dublin, the University of Dublin. 2015.
Figures 12a and 12b Codex Usserianus Primus, TCD MS 55, f. 135v, top right corner, showing several splits on the parchment due to the heavy ruling on a very thin skin. On the left is a detail during conservation with the caecum applied but still with the tissue facing on it; on the right the same area after conservation with the caecum holding the splits and the fragment inserted in its conservation mount © The Board of Trinity College Dublin, the University of Dublin. 2015.

Marco Di Bella, Senior Book Conservator, Preservation & Conservation Department, The Library of Trinity College Dublin

Footnotes

  1. J. Szirmai, The Archaeology of Medieval Bookbinding (London, 1999), p.15.