Collection Care blog

3 posts from May 2020

21 May 2020

Lotus Sutra Project: Conservation of a Scroll with Pre-11th Century Repairs. How Do We Avoid Disassociation?

Marya Muzart, Digitisation Conservator International Dunhuang Project

The Lotus Sutra Manuscripts Digitisation Project at The British Library, is a multi-year project aiming to conserve and digitise almost 800 copies of the Lotus Sutra scrolls in Chinese, with a view to make images and information freely accessible on the International Dunhuang Project (IDP) website. These manuscripts come from a small cave in a Buddhist Cave complex near Dunhuang, in Northwest China, where tens of thousands of documents, paintings and artefacts dating from the late 4th to the beginning of the 11th centuries were discovered in 1900. 

Out of the 800 manuscripts included in this project, a large portion of them need conservation work. This blog post covers the treatment of Or.8210/S.3455, and introduces the approach taken when we come across a scroll with historical repairs which are causing damage, but which we do not want to permanently separate from the scroll.

A scroll with historical repairs which are causing damage. Recto before treatment.

Picture 1: Recto before treatment.

A scroll with historical repairs which are causing damage. Verso before treatment.
Picture 2: Verso before treatment.

Or.8210/S.3455 is an 8-metre-long scroll with many historical repairs (we know that these repairs predate or date back to the beginning of the 11th century due to the provenance of the items in this collection). Carrying out repairs on damaged scrolls was a common practice in Buddhist monasteries, so we frequently come across historical repairs in the form of paper patches not only in the Lotus Sutra Project, but the Stein collection as a whole.[1]

These repairs are present throughout the scroll in varying sizes, however the two large historical repairs on the 1st and 2nd panel were the most challenging ones in terms of treatment. As we can see from the images above, the historical repairs in combination with the adhesive used were causing extreme distortion. As a digitisation conservator my aim is to ensure the item can be safely handled during digitisation and to ensure the text is visible and accessible so that high quality images can be taken. Not only was the scroll incredibly vulnerable to any handling, but its condition would have also made it impossible to produce suitable images during digitisation. This is why treatment on this scroll was necessary. 

Examining the scroll before treatment, it was clear that the historical patches needed to be removed in order to flatten the scroll and carry out repairs. Because the scrolls are archaeological artefacts, separating the historical repairs not only runs the risk of disassociation from the original manuscript, but it also takes away from its rich history as an object. This is why we always aim to avoid the permanent separation of any historical repairs from scrolls and I took the decision to reattach the historical repairs as a final stage of treatment.

How detrimental a historical repair can be, is dependent on the paper and the adhesive used. Thick paper and thick adhesive will cause distortions, as we can see in the images above. However, there has been evidence of some historical repairs applied very finely. So each historical repair that we see during the project presents a unique situation and treatment approach.

Verso after removal of historical repairs. Excess adhesive can be seen, which required further removal. 

Picture 3: Verso after removal of historical repairs. Excess adhesive can be seen, which required further removal. 

The first stage of treatment was to remove the historical repairs. After surface cleaning using a cosmetic sponge, gentle humidification was applied. Patience is key here, as I had to work one small area at a time using a micro spatula to slowly lift the historical repairs. It was important to get enough humidification introduced to soften and swell the adhesive for easy removal, but not so much as the paper would become extremely wet. You can see from the image above, once the historical repairs were removed, the dark crusty areas show how thick the adhesive had been applied, which further helps us to understand the distortions and tensions caused by this. The excess adhesive was further removed using the same technique; gentle humidification and a micro spatula. Any adhesive which was removed was kept in small sample bags for possible future analysis.

Once the historical repairs and the majority of excess adhesive was removed, the panels were flattened under boards and weights. When flattening was complete conservation repairs on the scroll were carried out using toned Japanese paper and wheat starch paste. When the conservation on the scroll was completed, it was time to reattach the historical repairs. 

The historical repairs were not reattached fully onto the scroll. Completely pasting down the historical repairs would simply cause the same damage as before. Instead, they were re-attached using some small Japanese paper tabs and wheat starch paste, each tab measures no more than a few millimetres and these are placed at strategic points underneath the repairs to stop any tension and subsequent distortion from occurring. These can easily be removed in the future if necessary, by simply cutting the small Japanese paper tabs, or by introducing gentle moisture to soften the wheat starch paste. It is important to note that the scroll spends the majority of its life rolled up, so the historical repairs were reattached whilst the scroll was rolled up. If they had been re-attached whilst flat there would be much tension occurring once it is rolled up. 

As you can see from the after treatment images, the historical repairs now do not create any tensions or distortions. The scroll can be safely handled and digitised by trained internal staff. By re-attaching the historical repairs, we have successfully avoided the disassociation that would occur from permanently separating the historical repairs from the scroll, therefore losing a part of its history. All in all, the treatment was successful.  

The historical repairs now do not create any tensions or distortions. Recto after treatment.

Picture 4: Recto after treatment.

The historical repairs now do not create any tensions or distortions. Verso after treatment.

Picture 5: Verso after treatment.

[1]  Rong, X. (2013). Eighteen Lectures On Dunhuang. Translated by Galambos, I. Boston: Brill, p.123.

14 May 2020

The Mahārnava, Conservation of a 19th Century Birch Bark Manuscript

Elisabeth Randell, Conservator (Books)

IO San 3251 before treatment.

Figure 1: IO San 3251 before treatment.

The British Library has a large collection of birch bark manuscripts. This particular manuscript was flagged for conservation because it was requested for digitisation. Unfortunately, due to its condition it was unable to be safely handled.

This manuscript known as The Mahārnava, from Kashmir, was written in Śārada on birch bark and dates from the 19th Century. The text discusses Hindu religious law (Dharmaśāstra) dealing with practices for removing and healing diseases and bad influences resulting from the deeds in a former life (Karmavipāka).

IO San 3251 front cover.

Figure 2: IO San 3251 front cover.

IO San 3251 back cover.
Figure  3: IO San 3251 back cover.

The text was compiled probably in the 14th century, and so the text isn’t so uncommon, however this manuscript still has its original limp vellum cover, which makes this example quite unique. The treatment plan for this object needed to fit for purpose, dealing with it more as an object rather than a manuscript that would be requested and used as a book.

IO San 3251 fore edge before treatment.

Figure 4: IO San 3251 fore edge before treatment.

Made from the bark of birch trees, each page is made of a laminate of birch bark - in this manuscript laminate of pages vary from 3 to 7 layers of birchbark. Layers of birch bark are held together from the natural resins and gum found in the birch bark, however overtime they naturally dry up and lose their adhesive properties, leaving many pages delaminated.

Detail of IO San 3251 delamination and tearing.

Figure 5: IO San 3251 delamination and tearing.

Almost all pages suffered from large tears and cracks, predominantly following the horizontal grain of the bark. The general fragility from inherent acidic characteristics of birch bark are made worse by the horizontal brown nodes which are more brittle than the surrounding bark due to a higher concentration of lignin, a material that gives off acids as it ages.  

IO San 3251 delamination and tears along nodes

Figure 6: IO San 3251 delamination and tears along nodes.

IO San 3251 old repairs.

Figure 7: IO San 3251 old repairs.

The nature of this material and method of production required a much different repair technique than would be employed for paper-based objects. For paper repairs stabilising a tear with a Japanese tissue on the recto or verso is a common technique. However, with this manuscript being made up of a laminate of organic material, it required a more considered approach.  Keeping in mind a balance of tension, and the many layers making up each sheet, a weaving technique was used to weave the repair tissue between the delaminated and cracked areas, where possible.

Example of repair options: inserting repair tissue between delaminated layers or weaving repair tissue between tears.

Figure 8: example of repair options: inserting repair tissue between delaminated layers or weaving repair tissue between tears.

IO San 3251 tear and delamination before treatment.

Figure 9: IO San 3251 tear and delamination before treatment.

IO San 3251 inserting toned kozo tissue on top of tear and between delaminated layers.

Figure 10: IO San 3251 inserting toned kozo tissue on top of tear and between delaminated layers.

IO San 3251 tear and delamination after treatment.

Figure 11: IO San 3251 tear and delamination after treatment.

Methyl cellulose 4% was chosen as the adhesive for its elastic nature, allowing the repairs and original material to flex naturally, and not become stiff as the old repairs.

Pages that had become loose were reattached to each other, weaving the tissue around original sewing to secure them in place.

IO San 3251 Japanese tissue hinges attached to both pages. Adhesive is applied to the Japanese hinges and attached to one another, repairing the broken spine fold.

Figure 12: IO San 3251 Japanese tissue hinges attached to both pages. Adhesive is applied to the Japanese hinges and attached to one another, repairing the broken spine fold. 

All repairs have been carried out and now the manuscript is able to be safely handled, pages can be turned without risk of further catching and tearing. Digitisation will be the next step for this manuscript so it will be available to a much wider audience, with minimal disruption to the physical object.

IO San 3251 fore edge after treatment

Figure 13: IO San 3251 fore edge after treatment.

IO San 3251 fore edge before treatment.

Figure 14: IO San 3251 fore edge before treatment.

IO San 3251 post treatment.

Figure 15: IO San 3251 after treatment.

08 May 2020

Conservation of 19th century ivory miniature portraits of the two young sons of Wajid Ali Shah

Patricia Tena, Conservator

In the late 18th century, British and European artists such as John Smart and Ozias Humphrey introduced the concept of painting portrait miniatures on ivory to local artists in northern India. By the mid-19th century, Indian artists also used relatively small ivory discs or sheets to paint topographical views and genre scenes as well. In 2018, the Visual Arts section added to its existing collection of works on ivory, two portrait miniatures reputed to be the infant sons of Wajid Ali Shah (1822-87), the last King of Awadh and date based on stylistic grounds to c. 1840-42.

Portraits of the two young sons of Wajid Ali Shah, the King of Awadh by an unknown Lucknow artist, c. 1840-42. British Library, Add Or 5710-5711

Portraits of the two young sons of Wajid Ali Shah, the King of Awadh by an unknown Lucknow artist, c. 1840-42. British Library, Add Or 5710-5711.

One of the two portraits show a young child of about 12 months old based on the fact he is pictured being supported by a bolster on the ground and cannot sit up properly. The second portrait displays a slightly older child of no more than 2 years old pictured seated in a European style chair. J.P. Losty (formerly the Head of Visual Arts) suggests that these two sitters were most likely to be the second and third sons of Wajid Ali Shah, as the first-born was deaf and mute and hence passed over. The second son being Falak Qadar ‘a fine-looking boy’ who would die prematurely of smallpox at the age of 11[1] and the third son being Hamid Ali (1838-74) would become the prince-apparent. Hamid Ali would later visit Britain in 1857, photographed by Leonida Caldesi at an exhibition In Manchester in July 1857[2].

On acquiring these ivories, the Visual Arts section arranged to have these portraits assessed and obtain proposals for the long-term preservation and storage. The miniatures came to conservation in late 2019 as part of the annual conservation programme.

The objects were both very vulnerable in the present storage box as the ivory substrates were effectively loose in the box and did not come with any ‘accessories’ such as backboards, glass or frame.  Both the watercolour media and the ivory substrate were in a stable condition. However, over time, there was considerable media loss mainly on the edges, probably caused by a change in frame/enclosure and being in close contact with a frame or glass that rubbed against the paint layer. Unsuitable materials such as adhesives and poor quality paper or card used for the framing will have contributed to the discolouration, accretions and staining on the edges.

Close up of one of the miniatures showing loss of media, accretions and discolouration on edges.

Close up of one of the miniatures showing loss of media, accretions and discolouration on edges.

As part of the treatment proposal, the pair of portraits did not require conservation treatment apart from cleaning prior to their rehousing. New enclosures were built in order to accommodate a very hygroscopic material such as ivory. One of the most common damage to ivory miniatures are cracks caused by a combination of restriction of movement to the ivory support and changes is the relative humidity. Ivory needs room to move within its enclosure; if it warps and the frame or support prevents it from doing so, it will inevitably crack.

One of the miniatures prior to being sealed in enclosure.

One of the miniatures prior to being sealed in enclosure.

The miniatures were hinged on top and bottom edges, then the hinges were threaded through a museum quality cream backboard and a Plastazote base. The hinges were secured onto the back of the Plastazote. The rest of the enclosures were built around the base, allowing space around the edges and between the miniature and the Vibac glazing. Mount backboards with Japanese paper flaps were provided to each miniature, these flaps were used to seal the Plastazote enclosures. The Vibac had to be slotted in place with a flush surround made out of mount-board. This allowed for a window mount to be adhered on the top to finish off the miniatures.

A buckram covered tray was made to measure taking care not to exceed the depth of the prints and drawings reading room drawers.  A Plastozote cut out was fitted in the tray to offer extra protection and prevent movement while being accessed by readers. The board with original inscriptions was mounted and rehoused in a Melinex enclosure, all made to fit the tray and to act as a protective ‘lid’ to the miniatures.

Finished miniatures and their tray.

Finished miniatures and their tray.

With the pair of ivories in their new housing, it is now possible to make the works available for consultation to registered readers by appointment.

For more on the historical background of these pieces head over to the Asian and African studies blog!

[1] R. Llewelyn-Jones 2014, p. 77

[2] Ibid, illustration no. 3.