Collection Care blog

Behind the scenes with our conservators and scientists

5 posts from July 2013

29 July 2013

Under the microscope with the Lindisfarne Gospels

Six of the British Library’s Anglo-Saxon and medieval manuscripts are currently on loan to Palace Green Library  in Durham City for their summer exhibition. The work of our Conservation Science and Research team was recently highlighted in a post on the Lindisfarne Gospels Durham website. Microscopic analysis is often used by our team as part of the condition assessment of fragile collection items.

Patience is a virtue

Tiny drops of red/orange colour produced from toasted lead are found throughout the Lindisfarne Gospels creating outlines, patterns and backgrounds for many of the folios. This type of decoration often appears in early Irish manuscripts. In Figure 1 a section of the initial page of the Gospel of St Luke on folio 139r was analysed with image processing software to determine the number of dots. 1,939 dots were found in just this one example area. It is no wonder that the manuscript’s production was costly both in time and materials!

Two images of a page from the Lindesfarne gospels. In the left hand image is the page in it's entirety, showing a large 'Q' (for Quonaim) stretching from top to bottom slightly left of centre, filled with intricate celtic style decoration, the predominate colors being shades of red, some blues and greens.The rest of the title text runs alongside, encompassed by a intricate border. The right hand image is a close up of the word 'Naim' (secodn part of Quonaim)  repeated in analysis, showing four tiered levels, the first the word itself in a rich gold and brown-red colour, the one below in black and white, the one below that in pink, and the last is a closeup showing the dots that make up the outside of the lettering.
Left: Folio 139r displays the initial page of the Gospel of St Luke.  Right: An image of one area containing the letters niam from the Latin Quoniam (Quoniam quidem multi conati sunt ordinare narrationem) was analysed to count the number of dots

The Lindisfarne Gospels are particularly remarkable given that the entire manuscript is thought to have been the work of just one man. A century after the production of the manuscript a note was added at the end attributing the work to a monk called Eadfrith who was the Bishop of Lindisfarne between 698 and 721.

Craquelure and crackling

Eadfrith's patience wasn't the only thing at risk of cracking up. Craquelure is a network of tiny cracks caused by pigment shrinking due to age. It is often seen on paintings where large grids of cracks are visible across the surface. When the disruption consists of perpendicular lines it is referred to as crackling, and the potential for formation is exacerbated when the pigment has been thickly applied. Crackling is seen in many of the pigments in the Lindisfarne Gospels, even in the tiny red dots used for decoration.

A page from the gospels, showing the parchement with the two parallel text sections, with Anglo-Saxon writing in red underneath each text. The parchment page also boasts a large richly decorated word 'Plures' as a new section heading. A more focused closeup of the section banner 'Plures', showing the intricate celtic style of the letter P(?), the black curved capital letters that follow, and the pink dots that are in the background of the banner, enabling the large text to stand out further on the parchment. Another close-up of the previous close-up, focussing in on the end two letters (E and S) and the pink or faded red dots concentrically laid out in even spacing around the black lettering.
CC zero Figure 2: Increasing views of folio 5v showing red/orange dot detail. The Lindisfarne Gospels are written in Latin but an Anglo-Saxon translation was added between the lines in red ink when it was owned by Aldred, Provost of Chester-le-Street in the 10th century

A very focused close-up of a decorated area, showing the orangey dots in the centre of a faded black banding of a letter. The Dots are stood out from the pageand appear as little rocks.
Folio 5v at 50x magnification.
A zoomed-in shot of the orange dots of toasted lead showing their irregular nature like slivers of stone in appearance. The lead dotsmostly all show cracks throughout.
Folio 5v 150x magnification. Tiny red/orange dots from toasted lead fill backgrounds of iron gall ink letters. Crackling is observed on the dots

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The exquisite suite of colours used in the manuscript was produced by Eadfrith using animal, vegetable and mineral pigments from both local and imported sources. A beaten egg-white preparation called glair was used as an adhesive and mixed with pigments. The black ink used for the main text of the gospel is iron gall ink made from oak-galls and iron salts, while a black pigment called lamp black containing particles of carbon was used in the illuminations. Green colours were produced using either verdigris, which is made by suspending copper over vinegar, or vergaut made by mixing blue and yellow pigments. The top of the decorated initial in Figure 4 is coloured with a yellow pigment called orpiment which contains arsenic trisulfide (As2S3).       

A page from the Gospels showing the neatly laid out latin text in black iron-gall ink, with the Anglo-Saxon translation underneath and to the sides of the text sections in red. A closeup of the page shows the elegant spacing and careful handwriting of the latin text, with the slightly less tidy translation around them. A delicately drawn title letter, possibly 'W' is decorated with green and yellow pigment.

Figure 4: CC zero Above: Folio 44v displays Latin text with decorated initials.

A zoomed-in image of the initial letter reveals the cracking of the green pigment which sits within the first hollow of the 'W', along with similar damage to the yellow pigment above it. The second hollow is either white or unpainted. Both sections and also along the outside of the black lettering, contain the toasted lead 'dots'. Within the letter hollows they are arranged as three.
Folio 44v at 50x magnification. This letter is filled with a green pigment of either verdigris or vergaut. The top of the initial is coloured with a yellow pigment called orpiment. Crackling is visible on both green and yellow pigments

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The chemical composition of the pigment contributes to the onset and degree of crackling. In the Lindisfarne Gospels, yellow orpiment shows the greatest degree of craquelure.

Another image of a full page from the Gospels, with latin text in black and Anglo-Saxon trnaslations underneath and to the side in red.An initial is decorated at left towards the top.  A close-up of the two letters - possibly or resembling 'IN'  with the black font highlighted and bounded by a line of dots of toasted lead. The upper part of what appears to be an N is filled with yellow pigment which shows cracking damage.
A further close-up of the previous image shows a closer look at the crackling of the yellow pigment.

Figure 5: CC zero Above Left: A partial image of folio 51v which contains mostly Latin text with some decorated initials. CC by Above Right: A decorated initial at 20x magnification. CC by Below: Folio 51v at 50x magnification. Red/orange lead dots border this initial which is filled with orpiment showing signs of craquelure

The entirety of the Lindifarne Gospels is digitised and available online at the British Library’s Digitised Manuscripts website, as well as being available on the Library’s interactive Turning the PagesTM feature. It is well worth spending some time looking through the various illuminations. Figure 6 shows a region of the manuscript at 50x magnification. See if you can identify the folio (the answer is posted here)!

A close-up of a section of illustration from one of the Gospels, focussing on the beautiful pink and purple pigments, separating by straight white lines in bounding black edges.
Figure 6: A 50x magnification image of a region on one of the carpet pages in the Lindisfarne Gospels.

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The Lindisfarne Gospels is an incredible human achievement and a truly spectacular example of medieval artistry. The exhibition at Palace Green library runs from 1 July to 30 September 2013. If you are in the Durham area it is well worth a visit.

Christina Duffy (@DuffyChristina)

Imaging Scientist

25 July 2013

Evolution or revolution! The changing face of collection care

Did you know that we are hosting a two day conference this October 2013?

A close up image from Alice’s Adventures Under Ground. A line drawing of Alice with long unbound hair, is lying, head resting in one palm, while a Rabbit in a coat trousers & shoes, walks past her, bearing a bouquet of flowers. There is writing from the text visible along the right and below the image.
“How puzzling all these changes are! I’m never sure what I’m going to be, from one minute to another!” Excerpt from Lewis Carroll’s Alice’s Adventures Under Ground.

CC by  View the entire book with our Turning the PagesTM software 

If you’ve been following our blog and are keen to learn more about collection care then you’re in luck: we have brought together a team of national and international experts and professionals in the field to share with us how change and development are redefining our roles and responsibilities. Speakers will be representing academic libraries and research libraries, colleges and universities, conservation institutions, archives, museums and galleries. You can hear from our own Collection Care team, too, as we’ll be on hand to chat about our own experiences in a changing environment and show you more of what we do and why. Places are filling up fast, but the good news is you’re still eligible for the early bird rate (£175 + 20% VAT = £210) which closes at the end of July!

Keynote speaker Bill Thompson (Head of Partnership Development at BBC Archive) will kick off proceedings on Monday 14 October discussing collection care in the age of electronics. A busy day of talks will be followed by a relaxing reception in the evening. Tuesday 15 is another bumper-packed day of presentations, and for anyone with the stamina to make it to Wednesday we will be running tours to various British Library departments including our state of the art conservation studios, our sound archive and a rare opportunity to visit our our low-oxygen, high-density store on our Yorkshire site. If that wasn’t enough there will also be a small trade event where exhibitors will demonstrate their latest products and technologies such as multispectral imaging.

There’s a lot of knowledge to be shared at this conference and we’re very excited to be a part of it. Hopefully see you there!

Book your place now. The full list of speakers can be found here and you can read more on the British Library What’s On page .

22 July 2013

Going Digital: Making manuscripts more accessible

Recently, a memoir and correspondence relating to a 20th century poet have come to Conservation to be prepared for digitisation. Some five years ago, we conserved another group of his letters. Superficially, the work was much the same for both: clean, repair and rehouse. But for the first batch the letters were carefully removed from an old guardbook and a new half-leather album made for them. Every item was cleaned, flattened where necessary, tears were repaired and losses infilled. Then each was hinged to a full support sheet, with compensation guards to accommodate the thickness and prevent the album from gaping. The work took 565 hours in all.

By contrast, treatment of the second batch of letters and the memoir was minimal: only essential dry cleaning and flattening plus some minor paper repairs, before they were rehoused as loose sheets in phase boxes; all completed within the estimated time of 20.5 hours.

A large paper tear close to the spine is running downand inwards, cutting through the flowing greek script on this manuscript a quarter of the way down the page.
Figure 1: A small edge tear can become more serious, if not repaired quickly. Here, a fragment of the text has been lost. (Add Ms 5873 f.105) 


What has changed? We are not cutting corners in conservation these days, but are responding to a digital revolution within the British Library, itself reflecting the needs and expectations of our users. Just five years ago, we accepted that famous poets were of great interest to our users. We knew their letters were, and (we thought) would continue to be, issued frequently in the Reading Room, and so we treated and rehoused them accordingly. The new guardbook provided greater protection and security, and the letters could be read with less handling.

This image demonstrates the loss of text, and therefore legibility, on this manuscript. The text, in greek script, is starting to disappear with the black ink no longer adhering to the page, creating a 'smudged' look. On the last line of three, most of the text has disappeared, with only an outline remaining.
Figure 2: Friable ink: a little more of the text is lost every time the manuscript is opened. Digitisation offers the “best available” reading to all, whilst the manuscript itself can be restricted until the ink has been treated. (Harley 5620)


The drive for digitisation had already begun, but we hadn’t then understood the implications for the use, and thus for the conservation, of collection items. Today, researchers (and the public in general) expect to have access to the collections via their laptops, tablets and smartphones, to share images and comments through social media and even to annotate our catalogues. The Library has long been willing to provide photographs or microfilm of collection items at a price; the demand now is for high quality digital images and free access. Digitisation projects are proliferating across the library.

In this image the loss of pigmment can be seen where the roll has been creased or folded. The close-up of the image is focussed on a area of an image in green with a red border, with the text in gothic script running parallel underneath the image.
Figure 3: The Henry Prayer Roll: Pigment losses at folds and creases caused by tight rolling and poor handling. The roll has now been rehoused on a wide core and is stored in optimum conditions, so we do not expect further losses. (Add Ms 88929)


Users of our digitised material find access easy from anywhere in the world and at any time of day or night. They also benefit from enhancements such as the ability to zoom in and discover details not visible to the naked eye. Frail material that is normally restricted - rarely issued in the Reading Rooms, and only viewed under supervision – is freely available on our website. So are treasures that can only be viewed as a single opening under low lighting levels in our exhibition galleries, some further enhanced by Turning the PagesTM technology. A digitised text is never unavailable because another reader is using it.

A page of a Greek manuscript showing the widely spaced tidy script flowing in two sections side by side. The image is focussing on the damage to the pager on the top right corner of the page, which has lost the defined corner, and is torn away, possibly by rodent damage, and folded in on itself. The corner itself is discolored through water damage, while there are specks of former mould damage.
Figure 4: A Greek Menologion damaged throughout by damp, mould and rodents. Full conservation is a major undertaking, but we can make the manuscript available more quickly by digitising it. A conservator works with the photographer, doing all the handling, to ensure there are no further losses or damage. (Add Ms 82957 f.3)


The collections benefit too. Items that get less physical handling are less likely to get damaged. They can stay in optimum storage conditions, rather than travelling to the Reading Rooms, and so deterioration is slowed. This is allowing us to rethink conservation requirements. Instead of heavy repairs to withstand frequent handling, we can now choose minimal intervention, just sufficient to allow material to be imaged safely. In some cases, we even send a conservator to help with the set-up and handling in imaging, as a less costly alternative to full conservation treatment.

A closeup inspection of the spine of this manuscript, lying on it's side, has revealed scraps of an earlier manuscript, used as spine linings in between three of the visible sewing bands.
Figure 5: A damaged spine reveals hidden evidence. The spine linings for this manuscript on paper are strips cut from an earlier manuscript on parchment, overlapping at the centre spine. It was common to recycle materials in this way. It is also possible to see the original double sewing supports and the sewing pattern. (Add Ms 78328)


The less we need to intervene, the more we can preserve original materials and structures – and this is becoming more important to researchers. Historically, rebinding was common to protect and preserve the text which was all-important, but now we understand that early binding techniques, indications of parchment or paper preparation, the composition of inks and pigments and much else are a reserve of material culture evidence, giving non-verbal insights into the past. If digitisation means items are issued much more rarely in future, there is less reason to replace weak original materials, or repair damage that is unlikely to get worse in storage; especially where, say, interesting binding structures can be glimpsed through losses in the covering. Rather than lavish six months’ conservation on a single item, we can apply our resources more intelligently, thinking more in terms of preservation and improving long-term storage conditions for whole collections. An example of this is the new low-oxygen newspaper storage facility at Boston Spa.

All in all, digitisation benefits us all; users, Collection Care and the collections themselves.

Ann Tomalak

16 July 2013

The conservation work behind our latest major exhibition, Propaganda: Power and Persuasion

Propaganda: Power and Persuasion, the first exhibition to explore international state propaganda from the 20th and 21st centuries, is now open in the PACCAR gallery at the British Library and runs until 17 September 2013. From the eye-opening to the mind-boggling, from the beautiful to the surprising, more than 200 posters, films, cartoons, sounds and texts reveal the myriad ways that states try to influence and persuade their citizens.

Work on an exhibition on this scale can begin anytime from three to five years in advance for the curators and others involved in the research and planning stages. Conservation’s involvement begins around six months in advance, assessing the condition of items from the Library’s collections that have been selected for inclusion by the exhibition’s curators. In the case of Propaganda, 195 items were assessed, 91 of which required conservation.

Over the following months the Library’s conservators worked to document, conserve, mount, and prepare these items for the exhibition. For Propaganda, 30 posters and 19 leaflets required flush mounting; six bindings required minimal conservation; several items required minimal paper repair; and several other items required mounting included textiles, banknotes, postcards, and stamps. In addition, around 40 items borrowed from private collections required detailed condition reports on their arrival at the Library and most also required mounting.

Part one of three images. This image shows a book, lying on a grey surface, titled 'New York World's Fair Cook Book' with a yellow map of the Eastern half of the United States of America in yellow on a blue background. The spine of the book is missing and the spine lining is exposed.    Part two of three images. A close-up image of the World's fair book, with a white piece of blotter paper lying on the cover, while a fragment of the spine is lying on top of .  Part three of three images. This image shows the New York World's Fair Cook Book after conservation treatment. The fragment of spine has been reattached and a new spine, in orange to replicate the lost original, has been bound into the book.
Conservation in progress: Crosby Gaige, New York World’s Fair Cook Book. The American Kitchen. Doubleday. 1939. All rights reserved

This recipe book from the Library’s collections required a book conservation treatment known as a re-back. New covering material is placed over the spine, re-forming the joints and head and tail caps, with the original spine covering adhered on top. A sympathetic colour match is chosen but there is no attempt to restore the missing areas.

Mounts, supports, and cradles must be made by hand for each of the objects exhibited, to ensure they are safely supported and displayed to the best possible advantage. This time-consuming and painstaking work is carried out by staff from both Conservation and Exhibitions to the highest possible standard.

Part one of three. This image shows a World War Two era silk handkerchief which consists of a colored Union Jack flag in the upper top left corner, with text in various languages to the right and underneath it. The name of the languge is in bold red, with the text in black. There is some light brown staining in the centre of the handkerchief. Part two of three. In this image which is focused on the bottom edge of the handkerchief, the hands of a conservator can be seen stitching the handkerchief to the padded mount-board using silk thread, the reel which is to the left of the item. Part three of three. This image shows a detail of the handkerchief after mounting. A portion of text in French is centre to the image, with the edge of the Union Jack flag can be seen on the left of the text.
Cc-zero This work has been identified by the British Library as free of known copyright restrictions.  Three images of the conservation of a World War II-era silk handkerchief.

This World War II-era silk handkerchief is a so called ‘blood chit,’ which was carried by Allied soldiers infiltrated into Japanese-occupied territories in Southeast Asia. It required specialist textile conservation mounting techniques to prepare it for display in the exhibition. A bespoke padded mount-board was constructed by one of the Library’s conservators using cotton fabric and swansdown and the scarf was invisibly stitched to this.

A technician, wearing a blue shirt, is seen in this image wielding a drill, whilst building a perspex book cradle in an exhibitions workshop.

Cc-by Above, a technician in the Exhibitions workshop making bespoke book cradles from Perspex

Books and other three-dimensional objects are supported on bespoke cradles. Cradles are made-to-measure for the individual book, supporting it at the correct opening angle for the pages that have been chosen for the exhibition.

An image of a eight-panelled colorised strip in Russian showing a child being raised according to Soviet values.    An image of the famous U.S. Army poster, showing 'Uncle Sam' with finger pointed, with text underneath proclaiming 'I Want YOU for U.S. Army'. the image is on a white/cream background with blue, white and red borders. The image is viewed from upside down.
Left: Alexei Komarov (artist), Every Woman Should Know How to Bring up a Child Properly.  Moscow, 1925. Loan courtesy of David King. All rights reserved. Right: James Montgomery Flagg (artist), I want You for U.S. army. c.1917. Loan courtesy of Anthony d’Offay, London  Cc-zero

Public information posters issued by Governments are among the most familiar forms of propaganda and there are many examples included in this exhibition. Above left is a poster from Communist Russia written in verse intended to promote good parenting of infants, and on the right is perhaps one of the most iconic images of war propaganda, J.M. Flagg’s Uncle Sam recruitment poster.

Many of the posters displayed in the exhibition are usually housed folded in books or stored rolled. Before mounting they need to be flattened and this is usually done by placing them between heavy blotting paper and non-woven polyester webbing under a light weight for a period of time to allow them to relax.

A view of tables, with the posters underneath white-colored Tyvek and weighted down to flatten them. Two grey high-backed chairs are on either side of the tables. A close-up of one of the posters showing a hinge of Japanese Tissue Paper on the bottom corner, to attach the poster to Mountboard.
Cc-by The posters are flattened under a light weight before mounting for exhibition

After flattening, evenly spaced small tabs of lightweight but strong Japanese tissue are used all around the edges to hinge the posters to 100% cotton museum mount-board. Approx. 2mm of tissue is adhered to the back of the object, just enough to secure it, and the remainder of the tab is then wrapped around and pasted on the reverse of the mount board.

Image one of three: A series of paper bags from the First World War era are shown on display. The cream-coloured bag are without handles, and display as posters, against a dark grey wall; white information placards are underneath. Image two of three: A photo of the exhibition space under construction. There is an empty display case, with a black base and a perspex display top in the foreground, and in the back is the exhibtion wall, with mounted and unmounted items covered in protective wrapping.  Image three of three: A staff member walks around the exhibition space. Similar to the previous image, the display case to the fore of the image is still empty, though some of the pictures in the background have had their protective wrapping removed.
Cc-by The paper bags shown above are an example of some of the more ephemeral material to be found in the exhibition

Smaller items such as paper bags, postcards, leaflets, and banknotes are usually mounted using archival polyester photo-corners instead of Japanese paper hinges. This type of mounting is suitable for temporary exhibitions but not for long-term storage.

There is very little turn-around time between exhibitions in the PACCAR gallery at the British Library. Staff from the Exhibitions department generally have only four weeks take down the preceding exhibition and coordinate build and installation of the new opening.

Exhibitions staff must work closely with Conservation, the Loans Registrar, and manage many external contractors to ensure that all construction work is completed and that all objects are safely mounted in their display cases.

Preventive conservation staff co-ordinate with Exhibitions to ensure that lighting, temperature, and humidity in the gallery are at optimum levels for preservation, and shortly before the opening the Library’s collection salvage teams visit the gallery to prepare a salvage and disaster plan.

Francesca Whymark

02 July 2013

Revealing hidden information using multispectral imaging

Our Conservation Science and Research team often receives requests for revealing hidden information. The manifestation of hidden information can be intentional (such as erasures and substitutions obscuring underlying text, e.g. Figure 1), or it can be a result of materials succumbing to the passing of time (archival degradation). Archival degradation is present in all materials due to natural aging and can be accelerated by usage, poor storage conditions, unsuitable humidity, mould, insect infestations, and physical damage such as fires or floods.

These conditions lead to typical deterioration artefacts including metal gall inks corrosion, ink diffusion and fading, seeping of ink from overleaf (bleed-through effect), blurred writings, fragmentation of ink or areas of ink loss. Attempting to capture what was originally underneath these artefacts can be very challenging. Each case is unique and it is often a combination of techniques which reveals information. One such technique used at the British Library is multispectral imaging.

Brown text written on a tan coloured paper. The writing appears rather jumbled as there is evidence of crossing out and writing over existing text.
Figure 1: An obscured inscription found on an incunabulum (IB.49437, Cordiale quattuor novissimorum [French] Les quattres choses derrenieres, translated by Jean Miélot)


Multispectral imaging is a non-invasive, non-destructive form of computational photography which can enhance difficult-to-read text using an extended light spectrum. The visible spectrum is the range of light wavelengths that can be detected by the human eye, and is what we often associate with the colours of the rainbow. Radiation either side of the visible region cannot be observed with the human eye, but can be detected in other ways. Image capture in multispectral imaging ranges from 420-1000 nm going beyond the visible spectrum into the ultra-violet (UV) where faded iron gall ink is enhanced, and into the infra-red (IR) where carbon underwriting and substitutions are revealed.

Faded text

Multispectral imaging was recently used to help catalogue an analogue tape from The Alan Cooban collection (C1398) for the Sound Archive. Mr Cooban recorded BBC transmissions off-air onto open reel tape from approximately 1957 to 1980. His metadata and labelling is excellent, for the most part. However, the very early tapes were housed in tin containers and in many cases the writing has worn away. Multispectral imaging was used on one such reel whose number was barely visible on the metal container it was housed in (Figure 2). A false colour image (which consists of an image combining green, blue and 800 nm images) was processed to reveal a possible number 34 or 37. Through catalogue cross-referencing and comparison with other tape labels it was confirmed as 34. The Alan Cooban collection comprises approximately 1900 tapes, and the Sound Archive has been transferring them for the past year and a half. They expect to finish this September.

This image is comprised of three different images from different levels of closeness. The image on the left shows very yellowed and degraded Sellotape on a metal container. The central image shows a close up of one piece of degraded Sellotape, but the naked eye can't make out anything aside from degradation marks. On the right, the multispectural imaging revels the word 'tape' and the number which is not entirely legible.
Figure 2: A faded label on an analogue reel from the Alan Cooban collection (C1398) is enhanced with false colour multispectral imaging



A palimpsest is a reused writing surface from which the original text has been scraped and washed away to allow the surface to be used again. Many palimpsests are found on parchment which was sometimes recycled due to its high cost and labour intensive production. In the case of medieval codices the original text is often found to be running perpendicular to the overlaid ink due to the manner in which the parchment was folded and cut for reuse.

Or. 6581 shown in Figure 3 consists of three single leaf palimpsest fragments from the Genizeh at Cairo, housed under glass. Hebrew commentaries of the 11th or 12th century are written over the original text. The largest of the fragments (shown in the centre and right of Figure 3) has old Palestinian Syriac under the Hebrew, rather than Georgian, as is found underlying text in the central fragment (reference: George Margoliouth's Catalogue of the Hebrew and Samaritan Manuscripts in the British Museum, printed in 3 vols. 1899 [reprinted in 1965]; v. 3, p. 579, and Oliver Wardrop’s A Catalogue of Georgian Manuscripts in the British Museum, appendix to Frederick Cornwallis Conybreare’s A Catalogue of the  Armenian Manuscripts in the British Museum, 1913, p406.).

The fragments were recently examined using multispectral imaging to generate new images which may aid in the reunification of neighbouring fragments. The style of the writing in the largest fragment resembles that of the fragment T-S. 12. 183 of the Cambridge University Library, with both potentially belonging to the same MS of the Bible.

Figure 3 comprises of three images side-by-side. On the left, we see three fragments placed in a triangular pattern under glass--that is, two fragments on top and one centrally beneath them. These fragments have writing in brown ink on an off-white surface. In the middle, a close up of the top right fragment is shown. It appears to us in a highly contrasted black and white, with the overlapping writing appearing quite dark and thus easier to discern than just viewing the fragment with the naked eye. The image on the right shows that same fragment, still in black and white yet with appearing to have less contrast now.
Figure 3: The three palimpsest fragments of Or. 6581 housed under glass. Multispectral imaging shows the largest fragment observed in the infrared (centre) and in the ultraviolet (right) part of the spectrum


Palimpsests are easier to extract and interpret using multispectral imaging. Images of all three fragments in the infrared, visible and ultraviolet regions of the spectrum were assigned to the colours red, green and blue to create a composite image shown in Figure 4, where palimpsest detail is enhanced. 

Figure 4 is three separate image showing each of the three fragments from above in detail. The imaging technique used makes them now appear in shades of blue, which help makes each of the written languages easier to discern.
Figure 4: Composite images of Or. 6581 palimpsest fragments showing improved detail


Multispectral imaging has many applications across the British Library and has helped in imaging watermarks, differentiating pigments and uncovering signatures. It has proven to be an excellent tool for information recovery and, combined with other techniques, enhances the scholarly understanding of many of our collection items.

Christina Duffy