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.
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.
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…
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 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.
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.
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.
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.
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..
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.
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.
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.
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.
Conservation of the “Book of the Constellations of the Fixed Stars” by ‘Abd al-Rahmān al-Sūfī
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.
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.
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.
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.
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.
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.
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 Red Book of Hergest, held in the Bodleian Library on deposit from Jesus College, was recently installed in the exhibition 4 Llyfr/4 Books : Welsh Icons United at the National Library of Wales.
Photos of the installation can be seen on the NLW’s facebook page.
In these pictures, we can see that during the exhibition installation some of the conservators were wearing gloves, and others not. Cotton or latex gloves are useful for those installing exhibitions, to prevent fingerprints on acrylic book cradles and glass display cases. But they are not always required for the handling of rare materials themselves. The Bodleian Library prefers that staff and readers have clean, dry hands – not gloves – when handling any rare books and manuscripts. The reasons are outlined in these posts from the University of Reading Special Collections and from the National Archives.
From 24-28 June, the Bodleian Libraries, in collaboration with the Oxford Colleges Conservation Consortium, hosted a workshop taught by Jiří Vnouček, of the Royal Library in Copenhagen. He led a team of conservators through the physical process of converting animal skins into parchment. At a lecture to a larger group of students, academics and library staff, Dr Vnouček related the appearance of parchment in medieval manuscripts to the process of production, drawing lessons for the technical examination and identification of parchment. The workshop, which is running for the first time in the UK, is generously sponsored by the Wellcome Trust, AMARC, Conservation by Design and the Leathersellers‘ Foundation.