Delving into Russia – Conservation for Digitisation

The Library is currently working with scholars from the Saint-Petersburg State University in Russia, on the production of a facsimile of our seventeenth century manuscript of The Life of Alexander Nevskij (CBL W 151).

The manuscript contains the Russian version of the mythical exploits of Alexander the Great written in Russian Church Slavonic. It is illuminated with 73 drawings in pen outline and colours. Alexander appears clean-shaven and is often seen riding a unicorn. On the pages, he battles fearsome creatures like the medusa, centaurs, hybrid dog-headed men and other fantastic beasts in far off lands. Another part of the manuscript, containing a copy of the Tale of the Rout of Mamai, is housed at the British Library in London (Yates Thompson ms 51).

w-151_f-39v-40r_after_conservation_edited

CBL W 151, f.39v-40r after conservation

The text and miniatures will be published as a volume in the series, “Written artifacts of Russian History and Culture, stored in foreign libraries and archives.”

To facilitate this work the complete manuscript has recently been digitised, but before that could happen, the manuscript required conservation.

slide1

The manuscript’s 20th century binding; f.12-13 before conservation showing the restricted opening characteristics.

The manuscript is bound in a modern brown calf binding, most likely added at the beginning of the 20th century. The binding was very tight and prevented the book from being opened fully, causing the folios to curve steeply, and leaving areas of each page obscured at the spine-edge.

In order to increase the opening of the manuscript, whilst still retaining its most recent binding, the book was gently eased open. This simple but careful treatment required the book to be opened slowly page-by-page from front to back. This was done three times to ease the binding sufficiently to facilitate digitisation of the inner most spine-edge margin.

2017_composite_images

Dorothea gently working through the manuscript to ease it open.

In addition some edge repair of the folios was necessary to make the digitisation process easier and safer. The paper textblock is very soft and many pages had tears along the edges. The manuscript had been extensively repaired in the past, with Western and Japanese paper. In some places these older repairs had partly detached, especially where close to the spine-edge.

slide3

f.117-118 before (left) and after conservation (right)

A decision was made to leave these old repairs in place and they were reattached where they were at risk of being lost entirely, especially along the spine fold. Edge repair was then carried out with acrylic-toned Japanese Kozo paper and wheat starch paste.

With the binding eased, and the textblock stabilised, the manuscript could be digitised. The book was put onto a cradle with an angle of approximately 110° and the camera lens was positioned parallel to the pages of the book.

slide4

Positioning the manuscript in the digitisation cradle. The folios are carefully leveled to align with the camera.

To further reduce handling, the book was digitised in two stages; firstly the recto pages were photographed, and then the verso. The pages of the book were held in place with polythene tape as necessary. When first assessed it was thought to be unlikely that the manuscript could be successfully digitised without extensive and interventive treatment. It was rewarding to see that the simple easing of the binding permitted the digitisation of the inner most spine-edge margin. The edge repairs prevented any further tears to the paper and safe handling by the photographic services team enabled us to digitise and eventually share this remarkable text. Slide5.JPG

Dorothea MüllerHeritage Council Intern in Conservation

Wishing everyone a very happy St Patrick’s Day from all at the Chester Beatty Library.

Advertisements

Internship in conservation

The Heritage Council and the Chester Beatty Library are celebrating the tenth anniversary of the conservation internship scheme. We are pleased to offer a twelve-month internship in book and/or paper conservation.

The scheme is co-funded by by the Heritage Council and the generous support of the Library’s Patrons. The internship offers the possibility of professional workplace experience within a prestigious institution.

2016_Cécilia.JPG

Cécilia Duminuco, carrying out pigment consolidation as part of her internship.

The successful candidate will gain experience working in the Library’s busy Conservation Laboratory. He/She will work under the supervision of the Library’s Senior Conservator, Kristine Rose Beers. Practical projects will be assigned to fit in with the Library’s on-going treatment, exhibition and loan programmes and include the preparation of manuscripts and single folios for digitisation from across the collections.

How to apply:

If you are interested in joining the CBL conservation team then further information and details on how to apply are available to download here.

You can learn more about the experiences of previous interns here.

A tale of twisting threads

With this post, we’d like to take the opportunity to welcome our new intern, Cécilia Duminuco. As we mentioned back in May, our internship programme is celebrating its 10th year, and we’re very happy that Cécilia has joined our team in this anniversary year. We hope you enjoy hearing about Cécilia’s work prior to joining the CBL Conservation team.

Before starting my internship at the Chester Beatty Library this November, I completed an MA research project at West Dean College, University of Sussex, in the U.K.

My research developed in collaboration with the Heritage section of the Maurits Sabbe Bibliotheek at the Catholic University of Leuven (Theology Faculty) in Belgium. I studied the sewing threads and sewing structures of twenty-four manuscripts and printed books from Western Europe, ranging from the 12th to the early 19th century, by means of two methods: visual assessments and Reflectance Transformation Imaging (RTI) with a Microdome, a digitisation tool created by the Catholic University of Leuven.

Fig1

Figure 1: the Microdome. Credit: Marc, P., Vandermeulen, B. & Watteeuw, L. (8/09/2014) “See the Surface. Imaging and measuring surface characteristics of library materials by photometric stereo (RICH Project)”, Digital Humanities@Arts Summer School, Leuven, p.8

In this post, I will briefly present the Microdome, the imaging technique attached to it and the results of the sewing thread analysis with this apparatus.

Reflectance Transformation Imaging (RTI) is defined by the Cultural Heritage Imaging organisation as “a computational photographic method that captures a subject’s surface and colour and enables the interactive re-lighting of the subject from any direction. RTI also permits the mathematical enhancement of the subject’s surface shape and colour attributes. The enhancement functions of RTI reveal surface information that is not disclosed under direct empirical examination of the physical object”. The technique was invented by Tom Malzbender in the Hewlett-Packard Laboratories in 2000-2001. In 2005, following Tom Malzbender and the Cultural Heritage Imaging organisation’s previous research, a new imaging device -a Portable Light Dome (PLD) – was developed in the Catholic University of Leuven.

The Portable Light Dome (PLD), also called Microdome, is a dome-shaped tool including two hundred and twenty eight LED white lights of four thousand Kelvin. A high resolution digital camera is mounted on top of the device. The object to be studied is placed in the centre of the dome, and several pictures with different lighting angles are automatically recorded. The images are then processed and viewed with specific software. The viewing software, PLDViewer, allows the researcher to analyse the created image through the use of several tools, such as a zooming and rotating functions, a measurement tool, and a 3D model exportation tool. This technique allows the surface characteristics of an object to be studied precisely, non-invasively. Furthermore, several filters can be applied to the image, allowing the creation of enhanced views of the surface (such as the Sharpen or the Shaded filters).

Fig2

Figure 2: Ambient light source and Colour filter, with light positions. Cod.4, pp.4-5.

Using a survey, I carried out visual assessment of each book’s sewing structure, before applying Microdome imaging on two pages of each book where the sewing threads were visible.

Fig3

Figure 3: Albedo light source and Shaded exaggerated filter, with light positions. Cod.4, pp.4-5.

In bookbinding, a sewing thread is defined as “a filament or group of filaments used for securing the leaves or sections of a book.” These filaments or fibres are most commonly of natural origin; sometimes from animal sources, such as silk and wool, or plants such as flax, hemp and cotton. Fibres were traditionally harvested by hand, and according to their nature they were subjected to different processes such as cleaning, combing and twisting before spinning. This is what results in each thread’s unique characteristics.

Thread twist count

The twist of a thread is defined as the “turns per metre of yarn, used to hold filaments together”. The number of thread twists per centimetre was analysed for forty-six thread samples using the measuring tool -a one-millimetre wide vertical or horizontal grid applied to the images.

Fig4

Figure 4: Twist count, Ambient light source and Sharpen filter. INC 805 EF_Etym, gathering beta.

Regardless of their date, the majority of the threads have approximately five to eight twists per centimetre (t/cm). In nine of the books, thread samples examined showed a consistent twist number range per book. However, in eleven books, the sewing threads had different twist numbers in each of the various samples analysed.

Fig5

Figure 5: Twist count, approximately 6t/cm. PBM 248.158_Hens Viri, pp152-153.

Twist angle

The twist angle is defined as “the amount of twist in a yarn measured in degrees”. The images of forty-eight sewing threads were studied after enhancement. In order to calculate the angles trigonometry formulas were applied by measuring the thread thicknesses (the opposite side of the right triangle) in combination with the twist measurements (the hypotenuse).

Fig7

Figure 7: A right-angled triangle ABC.

Fig6

Figure 6: Twist angle (A) measurements. Cod.4, p4-5.

All of the sewing thread twist angles measured ranged from 15° to 36°, with fourteen threads presenting a twist angle ranging from 20° to 25°. The smaller twist angles did not appear to be characteristic of a certain time period. However, the higher twist angles (more than 30°) were more commonly found in books from the 16th to the 19th century. It should also be noted that when considering threads in one volume, twist angles may vary widely. However, the majority of the threads studied presented relatively similar twist angles, within a narrow range.

Fig8

Figure 8: Twist angle measurements. PBM 248.158_Hens Viri, average ~23°, pp.152-153.

Thread thicknesses

Using the Microdome software measuring tool, thread thicknesses were also calculated in the samples. The majority of the sewing threads (forty-one samples) have an average thickness ranging from 0.40 to 0.80 millimetres. Five threads, from the 17th to the 19th century, are thinner than 0.40 millimetres; and twenty others, with no specific time range, have a thickness ranging from 0.50 to 0.65 millimetres. Twelve threads, nine of them from the 16th century or earlier, are thicker than 0.65 millimetres. Within a single book, sewing thread thicknesses vary. Similarly, within a single thread sample, variations in thicknesses can be observed

Fig9

Figure 9: Thread thickness measurements. INC 805 EF_Etym, average ~0.60mm, centre of gathering alpha.

In conclusion, all of the features studied revealed variations in the sewing thread structures. It seems likely that these variations could be explained by the hand-processing of the threads that were used.

A Picardy wheel. Engraving from Arts et Metiers, l'art du fabricant d'étoffes by J.M. Roland de la Platière, ~1780

A woman spinning fibres on a Picardy wheel. Engraving from Arts et Metiers, l’art du fabricant d’étoffes by J.M. Roland de la Platière, ~1780.

Analyses of these results has allowed me to define the advantages and limitations of both visual and analytical techniques for assessing books. In particular, the complimentary use of these two methods served to highlight the possibilities offered by the Microdome for use in the conservation field.

More details about the Microdome and my research will be presented at the Care and conservation of manuscripts conference in April 2016 in Copenhagen.

I am very grateful to Professor Lieve Watteeuw and to the Maurits Sabbe Bibliotheek of the Catholic University of Leuven who gave me such a wonderful opportunity to work with one of the most promising digitisation tools in the conservation field.

Cécilia Duminuco, Heritage Council Intern in Conservation

Paper, Pigments & Pearls: Conserving a Collection of Indian Miniature Paintings

The collection of Indian miniature paintings at the Chester Beatty Library (CBL) that forms CBL In 11A, contains 99 single folios from the Mughal era, dated from the late 16th to the mid-19th century. The folios include portraits of Mughal emperors, courtly scenes, natural history subjects and daily life. They are striking in their appearance due to the brilliance of the pigments used and the detailed nature of the paintings. The folios are often double-sided with both images and calligraphy, usually inset into highly decorative and pigmented borders. They were probably originally housed in bound albums, however, when sold at auction, they were often detached from their original bindings and sold as individual items.

in11a-69

Seed pearls and (perhaps precious) stones adhered to In 11A.69, Women on a Rock Slide, c.1760.

Following a request for access to a number of folios from this collection from a reader, I carried out an initial condition assessment. The decision was taken to conserve the entire collection, most of which had not yet been treated. Approximately half of the folios in the collection were adhered to acidic mounts with a full hinge along the left-hand edge, whilst others were mounted between glass plates, and a number were found loose without any form of mount.

The folios were carefully removed from their unsuitable historic mounts and examined visually. The sheer quality of the pigments is one of the first observations I made when examining these paintings. This has led me to become interested in the chemical make-up of pigments, which I will further study at the Montefiascone Summer School later this month. Examination of the folios was carried out using an Inspex High Definition digital microscope from Ash Technologies Limited. This microscope provides magnification of the object directly onto a large screen for detailed image analysis. This allowed me to determine which conservation treatments were needed.

slide21

Consolidating In 11A.67, A Dejected Mistress, 1755-1760, with localised brush application of Bermocoll.

The first step in conserving these paintings was the consolidaton of flaking pigments, which prevents further losses of the pigment layer. This is carried out using Bermocoll, which is a cellulose-based adhesive. A 1% solution was applied using a brush and a 0.5% solution was used in the nebuliser, which disperses the consolidant as a fine mist. Other additional, but infrequent treatments on these folios have included infilling areas of loss, and tape and/or adhesive removal.

In 11A.73_microscope_3

Pink pigment loss revealing under-drawing in In 11A.73, Ganesa and his Vehicle, 1800-1810.

Tears and other areas of damage have been repaired where necessary using a dry concentration of wheat starch paste and Japanese paper. The preservation of the In 11A folios is still underway, and the folios are currently in the process of being hinged into their new conservation standard mounts. This project is generously being supported by the Library’s members.

In_11A

Delamination of the paper support from In 11A.73, before, during, and after treatment.

During Heritage Week in August 2015, I will give a talk about this project. I will present a number of case studies and give more detail about the specific conservation challenges of these beautiful objects.

Puneeta Sharma, Heritage Council Intern in Paper Conservation

Puneeta’s presentation will take place in the Lecture Room at the Chester Beatty Library, at 1.10pm on Thursday 27th August.

Our internship programme is celebrating its 10th Anniversary!

The Library’s conservation internship programme started in 2005 and is generously funded by the Library’s Contributing Members and the Heritage Council. The programme has proved to be invaluable for both the Library and participating interns as Jessica Baldwin, Head of Collections and Conservation told us:

‘For the students it has offered a unique opportunity to develop practical skills while continuing their technical training as time is provided to explore new ideas and research. For recent graduates it also provides first-hand experience of working within a busy museum environment, which is essential to their career development.

Conversely working with the interns has also provided a great opportunity for the Library’s conservators to continue their professional development. The supervision and training of recent graduates has offered the impetus for extensive discussion on treatment approaches; this has resulted in the development or refinement of conservation practices within the Library. From a practical point of view the interns have had a very significant impact on not only the individual objects that they treat, but also the Collections as a whole, through their involvement in every aspect of work carried out in the busy Conservation Department.

On a personal level it has been an absolute pleasure to meet and work with so many talented, bright conservators and to be able to follow their careers as they go from strength to strength – not to mention making so many wonderful friends.’

Conservation Team CBL 2012 resize

The Library is delighted to be able to celebrate the tenth anniversary by inviting intern applications for 2015. If you are interested in joining the CBL conservation team then further information and details on how to apply are available to download here.

To mark the occasion, we have also invited our previous interns to introduce themselves and give an update on what they’ve been up to since leaving the Chester Beatty. Click here to read more.