ARCHiOx: research and development in imaging

A photo-essay by the Bodleian’s Senior Photographer and ARCHiOx Technical Lead for the Bodleian, John Barrett  

From plate to print: Left to right, albedo, normal map, depth map, shaded render, composite and original print. A copper plate portrait of antiquarian, Anthony Wood, recorded as never before, captured using the latest in three-dimensional recording technology. Rawl. Copperplates e. 65.

Producing objectively accurate images from the books and manuscripts in the Bodleian’s collections to enrich our growing digital archive is the primary focus of the Imaging Services department.   On occasion, requests from curators or clients may require our photographers to use specialist imaging techniques such as recording originals using ultra-violet light or infrared cameras.  However, for the most part the aim is not to reveal hidden details, but to produce faithful digital reproductions.

In contrast, the aim of a new research and development project now underway in the Bodleian’s  Imaging Studio is to record items from the collections in three dimensions, using entirely new technology, in the expectation that discoveries will be made through recording surface detail at extremely high resolution.

Almost invisible when photographed conventionally, the fine etching on the reverse of Rawl. Copperplates g. 21 is revealed. This composite digital image combines a shaded render of the surface of the plate, layered with an albedo (colour) image. The image depicts Invidia (Envy). No extant print made using this side of the plate has yet been identified. The etched lines are extremely shallow, measuring 0.029mm in depth. The plate measures a little over 10cm.

ARCHiOx –Analysis and Recording of Cultural Heritage in Oxford–is a collaborative project, bringing together the Bodleian Libraries and the Factum Foundation.  Based in Madrid, the Factum Foundation specialise in high-resolution 3D imaging and have worked in cultural heritage institutions throughout the world, producing exceptional, three-dimensional facsimiles of artworks and artefacts.

During this one-year project, experts from the Factum Foundation will provide equipment and training in the use of new technologies and assist in exploring ways in which the output from the project can surfaced in Digital Bodleian.  As the project progresses it is hoped that through the collaboration between technicians at the Bodleian and the Factum Foundation, solutions to improve and streamline the technology will be identified.

With generous funding support from the Helen Hamlyn Trust, the ARCHiOx project will continue until January 2023.  Thereafter the technology will remain at the Bodleian making it possible to provide high-resolution 3D capture as an ongoing service.

Unlike perhaps more widely-known 3D capture techniques such as photogrammetry, the two state-of-the-art machines used for ARCHiOx use different principles for recording volume and are specifically designed for the capture of low-relief surface texture.  This makes them well suited to the recording of the primarily flat, but texturally rich originals from the Bodleian’s collections.  This high-resolution, low-relief capture has been termed ‘2.5D’ rather than 3D.

The 2.5D data produced during the project will serve two purposes.  Shaded renders make it possible to view the surface texture of an original while removing their visible tone and colour.  This allows for academic research from originals that contain textural details which are difficult to see and cannot be adequately recorded using traditional photographic techniques.  Alternatively, the data may be used to produce 3D facsimiles from items within our collections, allowing the material nature of the original to be reproduced.

An example of a shaded render. Without the colour and tone of the original, the shaded visualisation shows only the surface texture of the original. A section of an 18th-century copper printing plate, Rawl. Copperplates e. 59, featuring Archbishop William Laud.

The Selene is an entirely new solution for capturing 2.5D data and is being used for the first time in the Bodleian.  Using computational methods to extract very detailed information about the surface of an object, the Selene records multiple 2D source images, each captured with meticulously positioned lighting.   The Selene was designed by Factum Foundation engineer, Jorge Cano and uses a principle called photometric stereo.  Captures generated with the Selene during the last two months have proved that the technology is capable of recording surface relief at an incredible 25 microns, or 0.025mm.  This is over three times the resolution of any technology previously used to capture cultural heritage material by the Factum Foundation.  

The Selene Photometric Scanner capturing one of the Lister copper printing plates in the Bodleian Library.

Taking two weeks to build and refine, the Selene was installed by designer Jorge Cano and engineer Matt Marshall in the Bodleian’s Imaging studio, in early February.  The Selene uses a high resolution camera and four custom flash units, which together can be moved horizontally over the surface of the original.  Multiple customised electronic modules synchronise the movement of the motorised guides with the triggering of each sequence of flashesThe Selene captures a series of image tiles at a resolution of 1040 pixels-per-inch.  The number of tiles, which is dependent on the size of the original can be programmed allowing for fast, automated capture.   

Man at a desk working on electronic components
Factum Foundation engineer and designer of the Selene, Jorge Cano, begins the assembly of the Selene Photometric Scanner in the Bodleian Imaging Studio.
Jorge Cano, testing and modifying the Selene Photometric Scanner, the only machine of its kind.

Unlike the laser recording system which has been used successfully for over a decade by the Factum Foundation, the Selene not only generates surface data, but can also capture colour.  This is hugely beneficial as not only does it make it unnecessary to capture the original twice but, due to being produced using the same source images, the shaded render showing surface texture and the colour image, known as the albedo, can be aligned perfectly to easily create a composite from the two.  We believe this composite image can be of great value to researchers, containing an exceptional level of detail and a real sense of the material nature of the original.   

A composite image, layering a shaded render of the texture with a shadowless colour image (albedo). This combination produces an image which shows every engraved line. (Lister Copperplates 858)

Created from multiple source images, each lit from different angles, the albedo is an exceptionally evenly illuminated and shadowless recording.  In some cases the albedo has a notable advantage over images produced using traditional lighting methods, which for 2D capture typically require just two primary light sources.  For originals with an uneven and highly reflective texture such as varnished paintings, creating an albedo may offer an effective solution for reducing unwanted highlights in reproductions. 

Factum Foundation engineer Matt Marshall installing custom flash units to the Selene.

Employing a very different principle to the Selene, the Lucida is a close-range, non-contact recording system that captures high-resolution surface texture data through the use of a laser and two tiny cameras.  This is a well-established solution for 2.5D capture, having been used by the Factum Foundation since 2011 during projects including the recording of the Tomb of Seti I, in Egypt.  The Lucida is capable of scanning taller originals, or those with greater vertical variation than the Selene and has been used extensively to produce data suitable for the manufacture of remarkably accurate 3D facsimiles.  Height data captured with the Lucida is incredibly accurate, though the resolution of the Lucida is significantly lower than the Selene in all three dimensions 

The Factum Foundation’s Lucida expert, Carlos Bayod Lucini (right), describes the technology behind the Lucida 3D Scanner to Bodley’s Librarian Richard Ovenden (left) and PhD researcher Chiara Betti. Photograph: Nick Cistone

The Lucida was installed at the Bodleian’s imaging studio by Factum Foundation expert Carlos Bayod Lucini. The data generated from the Lucida has been vital in two ways.  Comparing data between the two technologies has made it possible to determine an accurate elevation factor, allowing height measurements to be correctly estimated and recorded for depth maps produced with the Selene.  Through combining the two data sets by overlaying the high frequency information generated with the Selene, and the more reliably recorded gentle, but taller gradients measured with the Lucida, it has also allowed for the production an incredibly accurate depth map, using the combined strengths of the two recording systems.  This technically ambitious process is an important achievement in 2.5D capture and will make it possible to create 3D reproductions at higher resolution and with more accuracy than previously achieved by the Factum Foundation. 

Factum Foundation technician Celeste Anstruther modifies and tests the Lucida 3D Scanner

A selection of 18thcentury copper printing plates are amongst the first of the Bodleian’s originals to be captured with the Selene and Lucida.  Primarily from the Rawlinson collection, the plates include portraits of antiquarian Anthony Wood and 17th century Archbishop William Laud, as well as scenes, architecture and antiquities.  Plates from the Lister and Gough collections, the latter featuring portraits made from drawings attributed to William Blake, have also been recorded for the project.  Perfect for 2.5D capture using photometric stereo technology, copper printing plates have relatively flat surfaces and very shallow, highly detailed engraved lines The notable plates chosen for capture were selected by Co-ordinator of the Centre for the Study of the Book, Dr Alexandra Franklin and Chiara Betti, a PhD student at the University of London specialising in the research of the Bodleian copper plate collections on a Collaborative Doctoral Partnership, with advice from researchers who have worked on the Bodleian’s rare collections of copper plates and the associated publications.   As well as recording each plate’s text and illustrations, it is hoped that images produced during the project will reveal evidence of corrections, alterations, and degradation through use. 

A portrait of Edward III, from Gough Copperplates d. 107. The design is identified as the work of William Blake. These derivatives were processed using source images captured with the Selene. Left to right, shaded render, composite and albedo.

Notoriously difficult to capture using traditional photographic techniques, copper printing plates provide a number of challenges for the photographer hoping to record their surface.  There is little consistency in the material nature of the copper plates in our collections.  While some plates have been cleaned and are highly reflective with little change to their original colour and lustre, others, still bearing corrosion on their surfaces, reflect back virtually nothing and when reproduced, images may lack tonal variation and detail.

When photographing flat metal objects, the risk of capturing the reflections of the photographic equipment and the necessity to position the primary light source extremely close to the lens typically mean that a case-by-case approach is required.  This is a very different methodology when compared to the recording of paper and parchment originals, where a consistent workflow and continuous measurement is essential.

Using the Selene as an alternative to traditional photography has proven extremely successful, allowing us to record at a level of detail never previously achieved, and without having to navigate the complications previously associated with capturing metallic originals.

A tile image from Rawl. Copperplates e. 104. This composite was made by overlaying a shaded render and one of the colour, source images. The detailed engraving and colour would be extremely challenging, or perhaps impossible to reproduce using traditional photographic techniques.

Though capture of the source images using the Selene Photometric Scanner is relatively fast, currently the workflow required for processing the images is slow and reasonably complicated.  A number of software applications are required to generate the final derivative images, and one of the goals for ARCHiOx is to develop a more streamlined process.

Producing a normal map is the initial step in the process of creating useful derivatives such as shaded renders.  Normal maps are commonly used in CGI and computer game design.  Though the normal map is a 2D image, 3D information can be derived from the normal map because instead of simply recording a colour, each pixel represents a direction relative to the recorded surface of an original.   An entirely flat surface positioned parallel to the camera would be recorded on the normal map as a line, perpendicular to the original.  As the angle of the surface of the original changes, so too do the angles of the recorded lines, known as normal vectors.  Recording these normal vectors pixel-by-pixel makes it possible to map the surface of the original.  The direction of the normal vectors are defined by each pixel’s red, green and blue content.  Given that a copper printing plate is almost flat, the normal map represents the surface with an almost uniform purple colour.

A normal map produced with the images captured using the Selene. The starting point for producing useful derivatives, such as shaded renders.

Using the normal vectors from the normal map, a depth map can be generated.  This two-dimensional greyscale image uses tonal range to store elevation values.  It is processed at 16bits which allows for far more increments between tones to be recorded than in a standard 8bit imageThrough applying a Gaussian blur to the depth map, a derivative which records the gentle gradients over a wider area of an original can also be made.  In the workflow which has been established for the project, it is from the depth map that shaded renders can be created, using mapping software.   

Normal map to depth map integration. The angles of the normal vectors transform the flat profile of the normal map into a three dimensional surface. Diagram: Jorge Cano

In ordinary use, a geographic information system, or GIS application, can be used to create topographic maps and 3D visualisations of landscapes using aerial imagery.  By greatly increasing the scale factor, the same software can be used to map the tiny variations captured with the Selene and Lucida. The light direction and intensity can be configured, processing the depth map in to a highly detailed shaded view of the surface of the original. This shaded render can then be exported as a 2D image.

Though shaded renders provide an exceptional visualisation of the texture of an original, allowing researchers to virtually relight shaded renders for themselves is extremely useful as changes in the direction and height of the light can reveal details which may be hidden when recorded in a single shaded image.   In the case of the copper plates, engraved lines will either appear darker or lighter depending on the direction and height of the light.  As well as developing viewers capable of displaying and merging image layers produced during the project, Richard Allen, Andy Irving and Tim Dungate from the Bodleian Digital Library Systems and Services hope to develop tools that will permit this virtual relighting from the derivatives created from the 2.5D recording systems.

Virtually relit. Four snapshots of a real-time application written in Java. Using a normal map file as the source, it is possible for researchers to define the position of a virtual light source by simply moving the mouse pointer over the image. A section of Rawl. Copperplates e. 104.

One of the most important elements in developing the Selene is to establish an accurate elevation scale factor.  Height measurements are estimated when recording an original using the photometric stereo principle, and an elevation scale factor must first be assigned to the resultant depth map in order for accurate measurements to be made from it.  Comparing data from the Selene against data generated with a high-accuracy measuring device like the Lucida, or from an optical profilometer, has been essential in determining the correct scale factor. 

John Barrett (left) and Jorge Cano analyse a depth map using mapping software at the Factum Arte workshop, Madrid. The depth of a single engraved line can be determined by generating a cross section and measuring the vertical difference between peak and trough. Assigning an accurate elevation scale factor is essential prior to this analysis. Photograph: Matt Marshall

In order to reveal details from originals with extremely shallow relief, it has been useful to increase the scale factor and in doing so, exaggerate differences in relative height.  For instance, it has only been possible to produce usable shaded renders from many of the mezzotint printing plates captured for the project by increasing the scale factor.   

An extremely difficult test for 2.5D capture. A small section of a beautiful mezzotint copper plate, Rawl. Copperplates c. 41. The Selene manages to record the incredibly fine surface texture, but the detail in the shaded render can only be discerned by exaggerating the elevation scale factor. Left to right, shaded render, albedo and composite.

Creating and sharing an archive of detailed shaded renders will no doubt be extremely useful for researchers, but given that the data recorded for ARCHiOx is truly three-dimensional, the exciting possibility of creating accurate 3D facsimiles from items within our collections is entirely feasible.

For over twenty years, the Bodleian have archived hundreds-of-thousands of digital images, captured from our collections.  Through the use of technologies like the Selene and Lucida, we now have the capability of reproducing items more accurately than ever, not just as a two-dimensional representations, but as tangible 3D recreations.

This next-level development in preservation is not only important for the conservation of the original. Faithfully reproduced, three-dimensional reproductions will allow students to have a less restrictive, more hands-on experience of some of the more delicate and difficult to access items in our collections.  3D facsimiles may also be used as a substitute for originals while temporarily unavailable due to being exhibited or undergoing conservation treatment.

Two renderings of the surface of the same copper plate in close-up, showing the engraved lines
Truly three-dimensional. Two 3D views of the recorded surface of Rawl. Copperplates e.65, generated using mapping software. The second example shows a layered view, using the albedo and a shaded render. The depth of each engraved line, measured at around 60 microns, can clearly be seen.

Recreating an accurate and functional printing plate using data captured with the new photometric system is a demanding test for the Selene, but even more so for the elevated printing technology used to create the 3D facsimile.  While the Selene is able to record over 1000 pixels for every linear inch of original, Factum Arte’s state-of-the-art large-format 3D printer is limited to around half of this resolution.  Though this resolution has proved to be entirely adequate for the elevated printing of reproductions of artworks, the incredibly fine and often geometrically complex engraved details of copper plates are much harder to reproduce.

Commissioned by antiquarian Richard Rawlinson, Rawl. Copperplates e.65 is a copy of an earlier printing plate and features a wonderful portrait of local Oxford antiquarian Anthony Wood, whose manuscript and book collections are held at the Bodleian.  A print from the new plate, engraved in 1709 by Michael Burghers, appears in Rawlinson’s own copy of his work, ‘The Life of Mr. Anthony a Wood’.

So, not for the first time, though perhaps for the first time in 313 years, a new copy of the Anthony Wood plate would be remade, inked and pulled through a printing press.   This time however, the copy would be made using the very latest digital technology, in Factum Arte’s print room in Madrid.

A facsimile plate being 3D printed in the Factum Arte workshop, Madrid.

In order for the facsimile to be durable enough to be pulled through the printing press, it was initially necessary for the plate to be backed to a copper sheet.  Having prepared and inserted a base, the 3D files were then uploaded to the elevated printer.  The recently installed custom Canon Arizona printer deposits multiple layers of resin as the print head repeatedly travels over the base.  These incredibly fine layers, measuring between just 2 and 4μm are hardened using ultra-violet light.  Not only can the printer create texture, it can also reproduce the original’s colour.  The process is time consuming, taking several minutes to build even the shallow relief of the printing plate. 

The facsimile plate is made using an elevated printing process. Layers of resin are hardened using ultra-violet light.

With the elevated printing complete, the final challenge would be to print from the facsimile in order that comparisons could be made to the original prints from the Bodleians collectionsEager to produce the first prints, founder of the Factum Foundation, Adam Lowe used both a modern press and a replica Goya press to produce a preliminary batch of 2022 editions.  The prints are impressive, reproducing the incredibly fine cross hatching surrounding the central portrait.  This is an impressive achievement given that it is the first time that a printing plate has been produced using the new photometric stereo recording system.  It is likely that differences between the quality of the original prints and the reproductions can mostly be attributed to the limitations of the 3D printing technology rather than the 3D data generated by the Selene, but future developments in both technologies will no doubt lead to increased accuracy.

Founder of the Factum Foundation, Adam Lowe, prepares the facsimile plate for printing.
The inked facsimile.
Man operating a star-wheel rolling press to print an engraving.
The print is pulled through a replica Goya press.

Having now captured dozens of the Bodleian’s 18th-century copper printing plates for the ARCHiOx project, it has been a pleasure to show visitors to the Bodleian’s Imaging studio both the originals and the newly recorded digital renditions. The results from the Selene have generated a great deal of excitement from curators, conservators and researchers.  Coming at the same time as the doctoral research of Chiara Betti, and following publications by Anna Marie Roos, Jeremy Coote, and Mark Crosby, this project extends the library’s efforts to make these previously neglected relics of printing and book history accessible to researchers.

This technology has enormous potential for the capture of cultural heritage material and has greatly exceeded the expectations of all involved in the project.  But equal to the enthusiasm for the new technology and its output, visitors have universally expressed a greater appreciation of the skill and dedication of the engravers who made and printed from the original copper plates.  These items deserve to be recorded as perfectly as technology will allow.  In doing so these wonderful objects can be shared digitally for the research and enjoyment of everyone.

A composite of a Rembrandt portrait captured with the Selene for Agnews Gallery, London.

But recording a selection of the Bodleian’s copper printing plates is only the initial focus of ARCHiOx.    Now that the technology has been proven and refined, other collections which will benefit from 2.5D capture can be recorded.  From a Rembrandt portrait to a volume of Japanese Ukiyoe prints, and a mysterious collection of incised palm-leaf manuscripts, the Selene and Lucida will be used to reveal further exciting discoveries and record originals as never before.

Developments and output from the project will be recorded in a future post.

A Ukiyoe woodblock print from Nipponica 373. Albedo and shaded render.

Text and images (unless otherwise credited) by John Barrett, April 2022

With thanks for their assistance in writing this article:

Jorge Cano, designer and engineer for Factum Arte and the Factum Foundation.   Jorge is the designer of the Selene, has established the photometric stereo workflow used for ARCHiOx and has been responsible for my training with this exciting new technology.

Chiara Betti, researcher of the Rawlinson copper plate collection.  The working title of Chiara’s thesis is ‘The Rawlinson copper plates at the Bodleian Libraries’.  Readers with an interest in Chiara’s research are encouraged to contact her at chiara.betti@postgrad.sas.ac.uk. The research is funded by the AHRC through the Collaborative Doctoral Partnership. See: https://www.glam.ox.ac.uk/early-modern-copper-plates-bodleian-libraries

The incredible work of the Factum Foundation is documented on their website www.factumfoundation.org

This exciting project has been made possible through the generous funding support of the Helen Hamlyn Trust.

Textiles in Libraries: Context and Conservation

A binding with a gold and blue textile cover is displayed in an open purple box. There is damage to the covering of the spine which reveals the sewing supports underneath. The title of the project 'Textiles in Libraries: Context and Conservation' is overlaid.
Textiles in Libraries: Context and Conservation

The Bodleian’s Conservation and Collection Care team, in collaboration with the Centre for the Study of the Book, is embarking on a year of discovery in the field of Textiles in Libraries. The scope of this project is wide, from embroidered bindings to endbands, including textiles found between the pages, covering or wrapped around the binding, as well as the more unexpected places they can be found in library collections from tapestries to t-shirts.

As part of this project, the Library will be hosting a series of free online talks running from November 2021 to February 2022, bringing together conservators, curators and book artists to explore this topic further. Our speakers will highlight the many ways textiles are found in books and library collections, share case studies of collaborative conservation projects, examine what textile bindings can tell us about historic craft practices, and share examples of textiles used in contemporary book arts.

These talks will coincide with an exhibition held in Blackwell Hall of the Weston Library from November 2021, ‘The Needles Art’, which will show-case a selection of embroidered bindings from the Bodleian’s collections.

View the full programme and book tickets to the live talks here.

All talks will be recorded and publicly available to watch after the event.

The long influence of William Morris and the Kelmscott Press

Bodleian MS. Laud Lat. 102, a ninth-century manuscript rebound at the Bodleian LibraryBodleian MS. Laud Lat. 102, a ninth-century manuscript rebound at the Bodleian Library

Marking International Kelmscott Press Day on Saturday 26 June 2021, Bodleian Special Collections are counting some of the ways that William Morris’s knowledge and love of the book arts has contributed to library collections and expertise, up to the present day. (For more on this topic, join a lecture by Laura Cleaver, co-hosted online by the William Morris Society UK and the Institute of English Studies, University of London, ‘Medieval Manuscripts and Private Presses: William Morris and his Followers as Collectors and Creators of Books c. 1891-1914.’)

Bodleian Libraries Kelmscott Press d.6, The history of Reynard the Foxe
Bodleian Libraries Kelmscott Press d.6, The history of Reynard the Foxe

Morris’s devotion to book design was a deciding factor in the establishment of the Kelmscott Press, and this History of Reynard the Foxe (1892), reprinted from William Caxton, is one of the editions inspiring the forthcoming exhibition, ‘North Sea Crossings’, which will open at the Weston Library in November. But the influence of Morris is present in less visible ways, too.

Saddle stitching linking the cover to the text-block
Bodleian MS. Laud Lat. 102, Saddle stitching linking the cover to the text-block

Morris’s interest in the crafts of book making also included bookbinding and his work with T.J. Cobden-Sanderson (1840-1922) and the Doves Bindery, and his designs for the de-luxe binding of the Kelmscott Chaucer (1896) are well known. Much less well known is the profound influence that his choice of materials would have on future developments in book conservation and the rebinding of medieval parchment manuscripts. Described by Sydney Cockerell (1867-1962) in June 1896 as “a specially-designed binding which has been executed in white pigskin […] inside the skin are oak boards”, the choice of medieval bookbinding materials for the Kelmscott Chaucer was not obvious or entirely approved of by Cobden-Sanderson. Although Morris designed the binding in consultation with Cobden-Sanderson, the work was carried out by Douglas Cockerell (1870-1945) who in turn became the most important binder of his generation. His later conservation and rebinding of the Codex Siniaticus for the British Museum Library in 1935, with oak boards and alum-tawed goatskin, drew upon lessons learnt from the Kelmscott Chaucer and would set the standard for manuscript rebinding and be copied by others for many years. Assisting Cockerell with Codex Siniaticus was Roger Powell (1896-1990), another towering figure in the development of book conservation who would further refine the techniques for rebinding parchment manuscripts with his pioneering work on the Book of Kells for Trinity College, Dublin in 1953 – again bound with oak boards and alum-tawed skins. Powell in turn greatly influenced Chris Clarkson (1938-2017) who worked with him in the late 1960s. Clarkson would later become instrumental in the establishment of the Bodleian’s Conservation Section in the late 1970s and would further refine the techniques of rebinding manuscripts through close observation and appreciation of the structural qualities of surviving medieval bindings. Clarkson trained, encouraged and influenced many book conservators (and many at Bodley) and his approaches continue to be used and developed at the Bodleian today. MS. Laud Lat. 102, a ninth-century manuscript from Fulda, was recently expertly conserved and rebound in oak boards covered with alum-tawed calfskin by Sabina Pugh – the latest in the line reaching back to Morris.

Morris took an active role in the craft of book making. One statement of this commitment was given in the lecture, ‘On the woodcuts of Gothic books,’ available to read online from the William Morris Online Archive,

I cannot help feeling that it would be a good thing for artists who consider designing part of their province (I admit there are very few such artists) to learn the art of wood-engraving, which, up to a certain point, is a far from difficult art; at any rate for those who have the kind of eyes suitable for the work. I do not mean that they should necessarily always cut their own designs, but that they should be able to cut them. They would thus learn what the real capacities of the art are…

Matchbox art by Peter Lawrence, Engraver's Gallery
Peter Lawrence, Engraver’s Gallery (2015)

Peter Lawrence‘s ‘Engraver’s Gallery’ (2015), featured in a 3D rendition in the digital repository Cabinet, is a recent acquisition to the Rare Books collection which featured in a 2019 display ‘Thinking Inside the Box’. This tiny matchbox work repays close inspection. The cover features Morris in the act of wood-engraving (after the drawing by Edward Burne-Jones), shavings scattering around him, as we imagine, in an homage from one wood-engraver to another.

An engaged interest in the craft of making books as a way to appreciate them better, and to learn about the arts of earlier book designers, is the guiding principle of the Bodleian’s Bibliographical Press, where students, schools, and the public can undertake their own experiments to learn ‘the real capacities’ of the arts of printing.

– Andrew Honey and Alex Franklin

A rare books internship at the Bodleian Libraries contributing to the Provenance Digital Archive

from Victoria Higgins, Rare Books Summer Intern

Bodleian Libraries Lawn f.567, armorial binding stamp
Bodleian Libraries Lawn f.567, armorial binding stamp

When I was offered an internship in the Rare Books department of the Bodleian Library, I imagined my working days would not look entirely different to those of my English postgraduate degree – calling up material to the reading rooms of the Weston Library and searching through the pages of early printed books. Once lockdown was announced, I was grateful to learn that the internship would go ahead, except now later in the year, and entirely through remote working. Of everything shaken up by the crisis, my internship was probably low on the list of injuries. Nevertheless, I was uncertain about how I would proceed without access to the material. Thanks to my supervisor, however, I have never been at a loss for things to do. More than anything I think this time spent working for the Bodleian Library from home has made me consider afresh the value of “digital humanities” projects, and what is bound up in collections beyond the physical objects.

One of the main projects I have been working on is uploading to the CERL Provenance Digital Archive. CERL, or The Consortium of European Research Libraries, exists to “share resources and expertise between research libraries with a view to improving access to, as well as exploitation and preservation of, the European printed heritage.” The provenance project I was working on contributes to this mission, as individuals are able to upload to its visual database with ease. The effect when you enter the website is a jigsaw of carefully photographed bookplates, inscriptions, and bindings. Some are tagged with names and institutions, while many bear the elusive “Unidentified Owner”. Some are beautiful, such as an art deco style ex-libris belonging to “M.S.K.”, but many are visually unremarkable, plain ownership inscriptions and minor manuscript annotations. I was uploading marks of provenance found in the Mortara collection, bought by the Bodleian from Alessandro de Mortara in 1852. It dates from the 16th-19th centuries, and is particularly rich in 16th century Italian authors. What stood out to me working on this project was the number of hands these books passed through before they reached Mortara, and ultimately the Bodleian.

CERL prescribes a very particular process; upload one entry per mark of provenance. In practice this meant often uploading multiple entries from the same book, which had been marked by more than one individual. The idea is that a person would be able to search the archive for a particular mark – say a bookplate – and find images which match the one found in their book. In this way, the aspiration of the digital archive is to allow researchers to reassemble scattered libraries, as owners’ books were sold, auctioned and gifted to libraries and individuals across Europe. The project is still in its early stages and will be the sum of its parts, reliant on individuals choosing to take the time to upload their discoveries to the database. Nevertheless, working through these images from home I felt this was a digital space where near instant connection and collaboration was possible. It was exciting to think someone might recognise my unidentified armorial stamp or hastily scribbled name on a title-page.

http://arkyves.org/r/view/cerlpda_8ea9c/him_CERLPDA

Another project involved going behind the collections themselves to consider the personalities which formed them, as I was tasked with writing Wikipedia articles for some of the Bodleian’s named donors. It was fascinating to learn about the personal histories which drove these remarkable collections. An example is Brian Lawn (1905-2001), who was professionally a physician, educated at Sidney Sussex College, Cambridge. His profession seems to have driven his collecting, which is rich in medieval and early modern medicine.

Having purchased his first antiquarian book as a medical student, Cornelius Agrippa’s Vanity of Sciences (1684), Lawn’s lifelong collecting was motivated by an academic interest in the history of medicine. Perhaps against our presumptions about collectors, Lawn stated that his “books were bought for use and not for artistic or aesthetic reasons, many of them are what the booksellers used to call “working copies”.” He published two monographs on medieval problem literature, as well as an edition of the Salernitan Questions, considering their use in the history of teaching medicine and natural philosophy. What struck me is that there are similar stories of collections developing out of personal or professional interests for most of the donors’ biographies I explored. While I have often used rare books for my own research, I have rarely stopped to consider the individuals named on the shelfmarks. Spending time working remotely for the Bodleian has allowed me to think about the biographical histories which shaped the library as we encounter it today.

While it is a shame that I have not been able to go into the Bodleian Library and look at its materials in person, I have greatly enjoyed my internship. Working on rare books away from the objects themselves has made me think about collections in new ways, both in line with and separate from my academic interests as a student. It is safe to say that resources like the CERL Provenance Digital Archive are becoming more relevant than ever, and perhaps the time librarians will have spent on such projects during this time will help make their collections accessible to readers in new ways.

 

Victoria Higgins

Rare Books Summer Intern

Editors learn about paper, quills, and ink for closer reading

Traherne paper folding_1_blog

Members of the editorial board of the Oxford edition of Thomas Traherne’s (c. 1637-1674) works took part in a one-day workshop at the Weston Library, studying the ink and handwriting in manuscripts associated with Traherne’s works, including handwritten corrections in printed editions. They were guided by Jana Dambrogio, Thomas F. Peterson (1957) Conservator at the MIT Libraries, and a Sassoon Visiting Fellow at the Bodleian this month.

The first part of the workshop, hosted at the Bodleian Conservation studios by Andrew Honey, involved making iron gall ink (which has a dramatic colour change) and copper gall inks.

Participants had a chance to write with goose quills and steel nib pens on handmade paper, using chancery paper from the University of Iowa Center for the Book , with the help of papermaker Timothy Barrett.

Traherne quills_blogpost

Andrew and Jana talked about the western hand paper making process, ink making, quill shaping, and showed examples of other writing tools and materials (handmade sealing wax, stamps, paper making mould, pounce pots, etc.)

Participants all received a locked letter and later, in a seminar session, looked at three examples of folding techniques used by Thomas’s brother Philip Traherne (1635-1686), in letters preserved in Bodleian collections. Examination of major Traherne items from the collections, and additional material kindly lent by college libraries of Balliol, Brasenose, and Queen’s Colleges, formed the second part of the day. Balliol and Brasenose college library staff participated in the day with the Traherne editors.

The Oxford Bibliographical Society provided the funding for this workshop for the Oxford Traherne team.
The Oxford Traherne edition website: http://oxfordtraherne.org

The delights of flower painting: making colours that survive the centuries

From Richard Mulholland

With the Chelsea flower show in full swing, it’s a good time to return to the subject of the great 18th century botanical painter, Ferdinand Bauer, his paintings for one of the most splendid illustrated Floras ever produced, and the mysterious colour code he used to produce his paintings. Bauer, along with his equally talented brother Franz, is considered to be amongst the greatest botanical painters, and his work for the Flora Graeca (published 1806-1840)  amongst the most impressive achievements in natural history painting.

IMAGE 1

 

Bauer, as we discovered in the last post , was John Sibthorp’s chosen travelling artist on his expedition to Greece and the Levant in 1786. Sibthorp’s desire was to document the flora of the Eastern Mediterranean, following in the footsteps of Joseph Pitton de Tournefort, and updating Dioscorides’ De Materia Medica, the 1st century medical treatise that had been a standard text on the subject for over 1600 years.

When he came to Oxford in 1787, Bauer spent six years painting almost 1500 life-size watercolour paintings of plants and animals with astonishing colour accuracy – over 960 of these for the Flora Graeca. He did not paint in colour in the field, and reproduced his sketches in colour in his studio in Oxford using for reference only his memory, the dried specimens he and Sibthorp had collected, and a series of brief pencil sketches annotated with numerical colour codes that may have referred to a painted colour chart.

The Sherardian Library of Plant Taxonomy at the Bodleian has all of Bauer’s original watercolour paintings, most of his field sketches and most of the original herbaria specimens from the expedition. However, although there is evidence of a very early colour chart that may have been used by Bauer, if a colour chart ever existed for the Sibthorp paintings, it has been lost. The Bodleian’s Heritage Science department are working on a significant research project, funded by the Leverhulme Trust that aims to unravel Bauer’s code by looking closely at the materials and methods he used and try to understand how he was able to achieve such veracity of colour in his work.

Painting in watercolour in the 18th century was not as it is today. Although by the 1780s, a painter might purchase boxes of ready-made watercolour cakes (George Reeves introduced portable ‘moist’ watercolour cakes in 1766 that were a vast improvement on ‘dry’ cakes used previously), most painters still bought dry colour pigments in powder form from artists’ colourmen, druggists and apothecary shops, grinding them with plant gums and water to create their paints. The end product was usually dried and stored in mussel or oyster shells,  and could be reactivated with water as needed over the following few days.

“Reeves watercolour box c. 1772 taken on The Resolution by Isaac Smith” Museum of London 74.343/50. © Museum of London
Reeves watercolour box c. 1772 taken on The Resolution by Isaac Smith. Museum of London 74.343/50. © Museum of London

The Museum of London has a Reeves watercolour box that was in the possession of British naval officer Isaac Smith, who accompanied Captain Cook on both of his expeditions. Although the box was not taken on Cook’s first voyage on The Endeavour, Smith appears to have used  it on board The Resolution during the second voyage (1772-75), where the creation of surveys and maps were amongst his duties. There little evidence that professional travelling artists in the 18th century used commercial ready-made moist watercolours on their voyages, although they were popular amongst amateurs and professionals alike in the nineteenth century. The likely explanation may be that artists working in the 1770s and 80s would have learnt the art of preparing their own colours during a traditional apprenticeship and preferred to maintain their own quality control. However, the colours in this early box by Reeves are useful, as they are clearly labelled and therefore give us an insight into the watercolour pigments that were popular at the end of the 18th century, and a clue toward what we might expect Bauer to have used in his work.

The late eighteenth century also brought increased status to watercolour painting. Previously water based paints were generally used for either ‘washing’ (the hand colouring of prints and maps) or ‘limning’(the painting of portrait miniatures) or to ‘stain’ drawings. At the Royal Academy for example, watercolour was not considered in the same category as painting, watercolourists were regarded as ‘draughtsmen’, could only show their work in the lower ‘drawings’ chambers and were ineligible for full membership. In fact the Royal Academy did not admit watercolour painters as full exhibiting members until 1810.

Watercolour painting, as we think of it today however, had already emerged as a medium in its own right by the 1760s, and its status as an art form was cemented by the formation of the Society of Painters in Watercolour (now the Royal Watercolour Society) in 1804. With its newfound popularity, (especially amongst amateur painters from the nobility) from the mid-eighteenth century, numerous instructional manuals on watercolour painting were published, often concentrating on landscapes and flowers, and often containing lists of pigments recommended by the author for specific tasks.

‘The Delights of Flower Painting’ by John June, published in 1756 for example, contains a list of pigments, and instructions on how they should be prepared and used for painting flowers. With a few exceptions, most of these pigments are also contained in Isaac Smith’s watercolour box.

John June (1756) ‘The delights of flower-painting. In which is laid down the fundamental principles of that delightful art…’ D. Voisin, London. © British Library.
John June (1756) ‘The delights of flower-painting. In which is laid down the fundamental principles of that delightful art…’ D. Voisin, London. © British Library.

Such a selection of pigments would have been very familiar to Bauer, painting thirty years later, as there were few new pigments introduced to artists between the 1750s and the beginning of the 19th century. Using a number of analytical techniques, we are able to positively identify many pigments that Bauer used in his Flora Graeca paintings, and match them with his colour codes in order to ascertain whether certain numbers referred to specific pigments. The results show that Bauer’s code is certainly systematic, but also that he used a fairly traditional palette, considerably more like that of a 17th century miniaturist painter perhaps than a late 18th century watercolourist. Perhaps more surprisingly, he appears to have represented the myriad of colour seen across the Levant using only a small number of pigments in his palette.

We can pinpoint pigments by using very sensitive techniques such as Raman spectroscopy and XRF (X-ray Fluorescence spectroscopy), but using another technique – hyperspectral imaging – we are also able to ‘map’ Bauer’s pigments across an entire painting. The following example is from Bauer’s little-known Fauna Graeca paintings, equally impressive as his paintings of flowers. The false colour hyperspectral image composite highlights certain areas of the painting where he has used blue pigments. In this case, the areas that show as red indicate areas where indigo was used and areas that show as purple indicate those where a copper-based blue such as azurite was used..

Original image (below), and Hyperspectral false colour composite image (above) of Naucratus Ductor (MS. Sherard 239: Pisces, F43) showing areas of indigo (red) and copper blue (purple)” © Bodleian Libraries.
Original image (below), and Hyperspectral false colour composite image (above) of Naucratus Ductor (MS. Sherard 239: Pisces, F43) showing areas of indigo (red) and copper blue (purple)” © Bodleian Libraries.

Identifying the ‘what’ of course is very useful, but it doesn’t tell us everything about how Bauer worked, and in particular why he chose to use certain pigments and not others. One way to address this question is through historical reproduction – the recreation of facsimile paintings using materials and methods close to those Bauer would have used. Although Bauer is unlikely to have made his own pigments, the dry pigments we can purchase today are ground and prepared using modern techniques and are often prepared differently from those that were available in the 18th century.

Grinding vermillion pigment with a glass muller
Grinding vermillion pigment with a glass muller

We can get around this in many cases by manufacturing our own pigments using 18th century recipes. We know through our analysis that Bauer made extensive use of a copper-based green in his paintings of plants. In the case below, we created a batch of the copper green pigment Verdigris by exposing copper sheeting to wine vinegar over a period of time. The acetic acid in the vinegar reacts with the copper and forms an encrustation of green on the surface. This is scraped off regularly and then carefully ground into paint using a glass muller.

 

Making Verdigris pigment at the Bodleian
Making Verdigris pigment at the Bodleian

We know almost nothing about Ferdinand Bauer. There is no known portrait of him, very few letters, and almost no descriptions relating to his working procedures. However, this approach to art historical research provides an opportunity to gain an insight into his working life and perhaps a glimpse of his particular genius in creating these astonishing works of art.

 

Further information:

 

The Bodleian’s Head of Heritage Science David Howell will be speaking at a one-day conference on multispectral and hyperspectral imaging on 30 June. For more information and registration, visit: https://blogs.bodleian.ox.ac.uk/digital/2016/05/05/seaha-special-seminar-in-multispectral-and-hyperspectral-imaging/

 

On Saturday 25 June, members of the public can learn more about hyperspectral imaging by visiting the Bodleian’s Weston Library, where there will be demonstrations of this technique and Raman spectroscopy in Blackwell Hall. For more information, visit: http://www.bodleian.ox.ac.uk/whats-on/upcoming-events/2016/jun/scientific-research

 

And so to Bod… Antiquarian Booksellers visit the Bodleian’s Weston Library

Guest post from Laurence Worms of Ash Rare Books, who visited with a group from the Antiquarian Booksellers Association (ABA)

As part of our ongoing series of exchange visits between booksellers and rare book librarians (our friends and colleagues in the Rare Books and Special Collections Group of the Chartered Institute of Library and Information Professionals), a party of ABA members assembled in Oxford in mid November. Old haunts for me – parts of downtown Oxford almost unrecognisable after all these years, but beyond the city centre, up towards St Giles, things virtually unchanged in almost half a century. Far more young women students nowadays and far more bicycles (nothing less cool than a cyclist back in the ’sixties), but still recognisable Oxford types on every corner.
There were a dozen of us: ABA President Michael ‘Oscar’ Graves-Johnston; Brian Lake and Carol Murphy from Jarndyce; honorary member David Chambers; Sam Jonkers from Henley; Anke Timmerman and Mark James from Quaritch; Richard Wells from Teignmouth; Ann Gate (Waterfield’s); Tom and Sue Biro (Collectable Books), and myself. Slight chaos and confusion as we assembled in the Blackwell Hall at the Weston Library – two disparate tours scheduled to start at the same time. We were the quiet and well-behaved ones – no, really, we were – we couldn’t be much else in a hall named in honour of that great bookselling family, whose splendid shop still stands next door. Benjamin Henry Blackwell was ABA President in 1912, his son Sir Basil Blackwell in 1926.
The Weston Library is the new name of the New Bodleian Library on Broad Street, after its recent major makeover, rebuilding and refurbishment – renamed in honour of a £25 million donation given by the Garfield Weston Foundation toward its transformation (the Blackwell family chipped in £5 million too). The original 1930s book-stack has been moved down to the lowest basement level. The central stack has been rebuilt along with the installation of three floors of secure storage below ground level. The stone façade has been cleaned. New internal spaces have been created. There are now extra reading rooms and a fine public entrance hall. Above all, the Library is now equipped to store material in conditions laid down by the National Archives’ Standard for Record Repositories. This is critical in allowing the Library to continue to hold major archival collections accepted in lieu of tax and to receive vital funding.
Formally opened earlier in the year, we were to be given a guided tour behind the scenes. Rare Books Assistant Curator Lucy Evans led us first up to the Conservation and Collection Care Department . We were about to be impressed. At the first work-station, Sabina Pugh, the Senior Book Conservator, was working on a mediaeval manuscript of biblical exegesis rebound for Henry VIII – a manuscript presumably acquired and bound for the King at the time of the Dissolution of the Monasteries (1536-1541). Rebound in a regal mustard-coloured velvet, but now in need of work to allow safe handling and study. “I like to think Henry once handled and studied this book himself”, says Sabina.
Elsewhere, someone was working on an original Shelley notebook – and not just any notebook, but the one with the original draft of that ode which starts “O Wild West Wind, thou breath of Autumn’s being”. In another corner, work was being carried out on an extravagantly and exquisitely decorated Koran now starting to disintegrate – the vibrant and enticing green of the verdigris pigment the culprit, as so often. Lots of experimentation going on here with relatively new, virtually weightless and virtually transparent-in-use backing papers, and various types of adhesive. A mountain of thought before the intricate and time-consuming work can actually commence.
Fascinating for us booksellers and the source of some animated conversation later in the day. The whole thrust of library conservation is now towards as little intervention as possible – to render the material safe in handling but no more. No thought of restoration, refurbishment or replication of original glory – the Henrician binding to remain lacking some of its velvet, to remain lacking its original metal bosses – the repairs all visible and reversible. It’s a line of thought easy to understand: none of us would wish to intervene too far or to get things wrong. We have all seen disastrous examples of ill-conceived work – on the one hand, the clunky and charmless utilitarian rebinding which makes it fairly sure the book will not fall apart again, but leaves it almost impossible to open and deprives us of all sense of what it originally was, or, at the other extreme, the ruthless shearing off of catchwords and marginalia to present the book in the most finished and fashionable binding of the moment. Booksellers are often in a quandary here. We want to do the right thing, but we also want (and need) to sell the book. Our customers have their own expectations. We don’t exclude restoration or purely cosmetic repair. We don’t – at least most of us – exclude a complete rebinding in ‘period’ style or in a fine binding worthy of the text. Commercial binders can be exceedingly good at this – and there is, I believe, a duty on us all to ensure that the traditional skills of the bookbinder are kept alive. Perhaps time for a conference for all parties to exchange ideas and to attempt to achieve some kind of consensus about best (or at least allowable) practice?
Our tour continued with a special display of ‘treasures’ – chosen by the curators on hand to talk to us about them – some of their personal favourites, some prize recent acquisitions, etc. I was soon lost in contemplation of a wonderful recent bequest to the Bodleian – the exquisite ‘travelling library’ given to the young Prince Charles, later to become Charles I, in the early seventeenth-century. Sixty or so pocket books, worthy titles, the best of learning suitable for a prince’s education, uniformly bound and evidently intended to be a portable companion. So many questions unanswered: is the set complete, who assembled it and when, who bound the books – are these English bindings? French? – and, not least, where have the books been for most of the last four centuries, until they were put into their present red leather cases, made in the 1970s by Sangorski & Sutcliffe? What a research project in prospect.Dragging myself away from these adorable little books, I was soon equally lost in wonderment at the Bodleian copy of Shackleton’s extraordinary “Aurora Australis”, famous as the first book printed in the Antarctic, designed as a project to while away the long polar winter – but also, what I had never realised – a superb piece of printing in its own right.
Our afternoon ended with a complete tour of the building – up on the roof to catch the dreaming spires in an unexpected burst of late afternoon sunshine, a glimpse into the reading rooms and study areas, some encounters with the restored glories of the original 1930s fittings, furniture and ceilings designed by Sir Giles Gilbert Scott (he of the Telephone Box and Battersea Power Station). A pleasant end to a very pleasant afternoon – thank you so much to Lucy Evans and her colleagues for organising things and taking so much effort to entertain us. Our turn next.

Star maps restored: conserving al-Sufi’s text

Conservation of the “Book of the Constellations of the Fixed Stars” by ‘Abd al-Rahmān al-Sūfī

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from Robert Minte, Bodleian Libraries Conservation & Collection Care

A project to conserve and digitise a 6th-Century AH/12th-Century CE Arabic manuscript is nearing completion, enabled by a generous grant from The National Manuscripts Conservation Trust and private donations.

The manuscript, believed to be the fourth oldest extant copy of this important and popular astronomical treatise, is particularly significant to scholars as not many examples of book art survive from the period, and it contains unique illustrations of Bedouin constellations superimposed over Ptolemaic ones.

The manuscript’s fragile condition had necessitated restricted access for study and display, the priority for conservation being the stabilisation of its fragile paint layers and repair of the paper support corroded by green copper-based pigment used to illuminate chapter headings.

After detailed examination and assessment of the manuscript’s condition, the delicate and time-consuming task of repair was carried out with careful consideration of appropriate materials to be used in its treatment. A number of materials for consolidation of powdery paint layers were investigated, bearing in mind the need to minimise any introduction of moisture, which acts as a catalyst to copper-green degradation. This also informed the choice of a suitable adhesive for the repair of the fragile, copper-corroded areas and infilling of losses, using Japanese papers dyed to match the tone of the original paper: a very light-weight tissue to repair and support fragile areas, and a heavier paper to infill areas of loss.

The conservation and digitisation of this highly important manuscript will once again enable it to be safely studied and displayed.

Colouring by numbers: botanical art techniques investigated

From Richard Mulholland

[Author Richard Mulholland will give a lecture on Ferdinand Bauer and his colour code at the Weston Library on 3 June at 1 pm]

With the end of the annual RHS Chelsea Flower show on Saturday, and the masses returning to their own English gardens inspired, it’s worth looking back to the 18th century, to the golden age of botanical exploration and to an artist who was arguably the finest botanical painter in history, Ferdinand Bauer. Now the Bodleian’s Conservation Research department are helping to unravel his meticulous and unusual painting technique.

Ferdinand Bauer, Iris Germanicus, watercolour on paper
Ferdinand Bauer, Iris Germanicus, watercolour on paper (MS. Sherard 245/70) © Bodleian Library, University of Oxford 2015

Outside of the natural sciences, Bauer (1760-1826), is little known. However, along with his equally talented brother Franz, he is certainly known to botanists. He has been called ‘the Leonardo of botanical illustration’, and is known in particular for the beauty and accuracy of his illustrations of flowers. Nowhere is this seen more clearly than in the paintings he made for the exquisite Flora Graeca, one of the most rare and expensive publications of the 18th century, and certainly one of the greatest botanical works ever produced.

Unprecedented in the quality of its illustrations, its printing and its attention to naturalistic detail, the Flora Graeca described the flowers of Greece and the Levant, and was published in ten lavishly-printed volumes between 1806 and 1840, purchased by an elite list of only 25 subscribers. It was the legacy of the third Professor of Botany at Oxford University, John Sibthorp (1758-1796) who funded much of the endeavour out of his own funds. Sibthorp met Bauer in Vienna in 1786, and immediately engaged him to join his expedition to collect and record specimens, and ultimately to paint the almost 1500 watercolours of plants and animals he sketched on his return to Oxford in 1787.

 

James Sowerby (after Ferdinand Bauer), Frontispiece [Mons Parnassus] for The Flora Graeca, 1806-40, hand coloured engraving (MS. Sherard 761).
James Sowerby (after Ferdinand Bauer), Frontispiece [Mons Parnassus] for The Flora Graeca, 1806-40, hand coloured engraving (MS. Sherard 761). © Bodleian Library, University of Oxford, 2015
 What is of interest to us however is that Bauer used a particularly unusual technique to record his specimens in the field.

Bauer is exceptional among travelling botanical artists for the unusual techniques he employed for recording colour. He certainly observed and sketched live specimens, but he did not annotate these sketches with colour in the field as other artists did. Rather, subject to the limitations of working in the field – moving from place to place quickly in often difficult territory, and unable to carry large amounts of painting materials with him, he made only very basic outline sketches in pencil on thin paper.

He recorded the vital colour information, lost almost immediately after a specimen had been picked by annotating these with a series of numerical colour codes which likely referred directly to a painted colour chart, now lost. That Bauer’s paintings were created using only this colour reference system during his 6 years in Oxford, painting them sometimes up to five years after seeing the original plants, and that they are highly regarded even today for their botanical accuracy, speaks to his expertise as an artist and his astonishing memory for colour.

Page from sketchbook for Iris Germanicus showing numerical colour codes, graphite pencil on paper, 1786-7 (MS. Sherard 247/107). © Bodleian Library, University of Oxford, 2015
Page from sketchbook for Iris Germanicus showing numerical colour codes, graphite pencil on paper, 1786-7 (MS. Sherard 247/107). © Bodleian Library, University of Oxford, 2015

More pertinently, Ferdinand Bauer (and to a lesser extent his brother Franz) appear to be the only significant natural history artists to have used this kind of colour code in a practical way. Numerical codes of up to 140 different colour tones are found on early drawings by both Bauers from the 1770s. However, where Ferdinand seems to have continued to develop this initial system of some 140 colours into one of at least 273 colours for the Flora Graeca (and from then into a considerably more complex system of 1000 colours for a later expedition to Australia in 1801-5 – though how he could have used this practically is anybody’s guess), Franz Bauer, who was by then official botanical painter to Joseph Banks at the Botanical gardens at Kew, did not did not appear to use the system after he came to London in the late 1780s. Ferdinand of course, spent a significant amount of his time working in the field, and therefore much more in need of a system of shorthand than his brother. However, it’s interesting to note that no other travelling botanical artist used such a system to the extent that Bauer did.

An early colour chart (below) that appears likely to have been used by the brothers was found in 1999 at the Madrid Botanical Gardens, but Ferdinand Bauer’s 273 colour chart from the Sibthorp expedition and the 999 colour chart he may have used for the Matthew Flinders expedition to Australia, if they ever existed, have never been discovered.

Colour chart (c.1770s) discovered in the Archives of the Botanical Gardens in Madrid in 1999, and likely to have been used by the Bauer brothers © Archivo del Real Jardín Botánico, CSIC, Madrid.
Colour chart (c.1770s) discovered in the Archives of the Botanical Gardens in Madrid in 1999, and likely to have been used by the Bauer brothers © Archivo del Real Jardín Botánico, CSIC, Madrid.

This fact, however, presents a unique opportunity for us to carry out technical research into Bauer’s materials. The Conservation Research department at the Bodleian Libraries together with the Plant Sciences Department at the University are working on a three year Research project on Bauer’s techniques, funded by a Leverhulme Trust Research Project Grant. Collaborating with the V&A, Durham University and the University of Northumbria the project aims to understand what the Flora Graeca colour chart may have looked like, and how Bauer might have used it. A large part of the project involves identifying the pigments used by Bauer in his magnificent Flora Graeca watercolours, cross reference these results with the numerical codes in his field sketches, and ultimately create a historically-accurate reconstruction of the lost colour chart.

Professor Andy Beeby from Durham University setting up a portable Raman spectrometer to analyse red pigments used on one of Bauer’s paintings © Bodleian Library, University of Oxford
Professor Andy Beeby from Durham University setting up a portable Raman spectrometer to analyse red pigments used on one of Bauer’s paintings © Bodleian Library, University of Oxford

How will we do this? Often it is permitted to remove a minute sample of paint from a work of art in order to identify the material components. However this is rarely possible with works of art on paper, and is most certainly not possible for one of the treasures of the Bodleian’s collection! The work therefore is carried out in situ, bringing portable instruments to the object itself, rather than the other way around. For this we currently use three analytical techniques at Oxford: Raman spectroscopy, X-ray Fluoresce spectroscopy (XRF) and Hyperspectral imaging (Imaging spectroscopy).

Durham and Northumbria Universities have particular expertise in Raman Spectroscopy of cultural heritage objects, and Durham has built a portable instrument that is capable of positively identifying many of the pigments that Bauer used. The V&A Conservation Science section has a long history of collaborating with universities on technical research, and also has a great deal of expertise in Raman spectroscopy and its use in identifying pigments on artists’ watercolours.

In addition to the excitement of recreating Bauer’s lost colour chart, the project showcases the value of technical art history, a relatively new field that encompasses both scientific analysis and historical research into the materials and methods of the artist. It will go some way toward an understanding of Bauer’s extraordinary feel for colour and pigment, how he utilised his colour code, and ultimately how he was able to achieve such an impressive degree of colour fidelity in his work.

As we progress with the project, and as we learn more about Bauer’s materials and techniques, I’ll post again with more results. But should you find yourself in Oxford before September, a copy of both the Flora Graeca, and Bauer’s original illustrations for it are on display in the Marks of Genius exhibition at Bodleian’s Weston Library.

The first printing revolution re-examined: Oxford Bibliographical Society

12 May 2014: The Oxford Bibliographical Society hosted Cristina Dondi speaking about ‘the first printing revolution’ and our understanding of the transformation of the economics of communications.
Citing the many copies of 15thc-century books with former owners’ inscriptions or just localisable and datable decoration, and binding style or manuscript annotations, Cristina Dondi explained the possibilities of using books themselves as evidence for the impact of printing in transmitting texts and images.
The aim of the ERC-funded project headed by Dr Dondi, beginning this year, “The 15th-century Book Trade: An Evidence-based Assessment and Visualization of the Distribution, Sale, and Reception of Books in the Renaissance“, is to gather evidence from early printed books, to analyse and categorize the marks of ownership, by geographical area, period, or person (gender, status, and profession). This is the approach established by Dr Dondi in the database, Material Evidence in Incunabula. The current project will seek also to more closely analyze the textual contents of editions (not just the main text and author, but all dedications, prologues, etc.) This approach extends the practices of Bod-Inc, the catalogue of 15th-century books in the Bodleian, and promises to expand our knowledge of the transmission of texts in the early period of print.
A further exciting development will be image matching analysis of illustrations in Venetian incunables, using the image matching software developed by the University of Oxford Department of Engineering for the Broadside Ballads Online database hosted by the Bodleian Digital Library.

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