§ 1 Digital Mappaemundi (DM) is a resource under development to generate open source tools for scholars to edit and annotate image data that are networked together, and for other users to search within this rich content. For the purposes of development, our data have been medieval mappaemundi ("maps of the world") and their geographical source texts. With funding from a 2009-2010 NEH Digital Startup in the Humanities grant, as well as a 2010 Scholarly Communications grant from the Andrew W. Mellon Foundation, the DM project team has finished the first stage of development, and worked through foundational issues of functionality, data management and interface. At the time of this publication DM has undergone significant evolution during its phase three beta development and is now a broadly applicable environment for the creation of annotation and linked data across a range of digital image/text collections. The use-case referred to "Digital Mappaemundi" in this essay is now the "Virtual Mappa Project" (VMP), and is in partnership with the British Library. For current functionality and features of the DM environment, as well as a list of medievalist projects using it, see http://ada.drew.edu/dmproject/.
Background and history
§ 2 In 2002, after finishing The Bayeux Tapestry Digital
Edition (BTDE), Martin Foys began to look for another project to continue
his work in applying digital technology to the study of early medieval artifacts. One
of the things that drew Foys to the Tapestry in the first place was its hybrid nature
of expression, and the way that its monumental materiality (over 230 feet long and
containing four simultaneous registers of graphic and textual information) resisted
traditional modes of printed scholarship (Foys 2007,
102-109). Medieval maps, particularly the Cotton Map, an Anglo-Saxon mappamundi from around the year
1000, became an ideal subject. Not art, not literature, not history, and from a
long-standing and biased view of modern cartographic scholarship, not even a very
good map, the Cotton Map had easily fallen in between disciplinary cracks. The
initial approach was a remediating and docucentric one: create an edition of a single
artifact in the same template as the BTDE, as a standalone edition
published in a physical and
closed format (CD-ROM) (Figure 1). Less than a decade later, the impulse to
create such a publication reads as quaint, if not antique.
§ 3 During this time, XML emerged as the dominant standard for data markup. Foys partnered with Asa Mittman and a group of student researchers to mark up in XML the Cotton Map and several source and analogue geographic texts, including the Latin and Old English versions of Orosius's description of the world from Adversus Paganos Historiarum Libri Septem ("Seven Books Against the Pagans"), the Bible (selected content specific to Cotton Map), the twelfth-century Expositio mappe mundi, St. Jerome's De situ et nominibus locorum hebraicorum liber (selected), Isidore of Seville's De natura rerum (selected), Pliny the Elder's Naturalis historia (selected) and Solinus's Collectanea rerum memorabilium (selected). This team used a modified version of the Electronic Production and Presentation Technology (EPPT) software that Kevin Kiernan and his team had developed to mark up transcriptions of manuscript folia (see Figure 2). In EPPT, the project was able to tag coordinate bounding boxes on an image of the Cotton Map in XML, and relate these coordinates not only to a textual transcription of the map's 147 Latin inscriptions, but also to specific moments in one or more of the source/analogue texts. In the midst of the process, it became clear that this kind of electronic editing could be used not in the service of one map, but rather to build a database network of medieval maps and texts that could be continuously expanded in the future by other users. Once other maps were edited, their coordinate-based XML tags could be used to cross-reference details within maps to their analogues on other maps, allowing for an innovative architecture and scale of comparative study. This realization served as the genesis of Digital Mappaemundi. In 2008, Foys moved to Drew University and Shannon Bradshaw, a computer scientist, joined the project as co-director, and work developing the data architecture and end-user interface began in earnest.
Background: Geospatial bias and the nature of maps
§ 4 In
Using Digital Primary Resources to Produce
Scholarship in Print, John Unsworth
new possibilities for print scholarship are presented by
born-digital information and the tools one uses with that information—to take just
one example, consider geographic information systems [...] that map all kinds of
social information onto geographic space. When people hear the DM project
is working on technologies and maps, there is often a frustrating, if understandable
response that assumes work with GIS (Geographical Information Systems) or maybe
Google Earth. Such assumptions often go hand in hand with a curious tendency towards
geo-rectification – that is, to take maps of the past world and align them to the
mensurable reality of today's world's physical topography. Over the past five years,
common approaches to historical geography and mapping have rapidly become synonymous
with modern, measured, plotted and/or georectified spaces. For example,
Mapping Medieval Townscapes: A Digital Atlas of the New Towns of
(Lilley et al. 2005) creates a
modern, accurate map on which medieval historical information and topography can be
plotted. As such, it subordinates all content to current notions of geospatial
representation and reality. Another common technological trope for the cartographic
past is to take an old map and fill it with new knowledge. In the Map of Early Modern London project
(Jenstad et al. 2010), for instance, students
and scholars have linked "encyclopedia-style articles, scholarly work, student work,
editions, and literary texts" to ‘hotspots’ on the 1578 Agas map of London. In this
case, the resulting, rich resource seems less focused on the map itself than it does
on gathering all kinds of information that can be added to it in digital form.
§ 5 This is in no way to discount the immense value, utility, and promise, of such resources as those described above. But they do unwittingly represent a tacit, largely unexamined assumption about what maps of the past are to us today and they explicitly measure the past views of the world against the present. The result is often a distortion of our critical understanding of them as we attempt to remake the older map into a repository for some other kind of information (Figure 3). What remains less fulfilled, technologically, is the excavation of the content already there on such maps. For digital projects focused on historical material to be fully realized, they must also grapple with material on its own terms, and acknowledge its particular concerns. Medieval maps are far more similar to literature or art in that they are representations that are not necessarily grounded in the specifics of our reality. They were not designed to correspond point for point with the globe—precision of distance and detail, a foundation of modern cartography, was irrelevant. Rather, medieval maps were aimed at helping their largely monastic audience understand their place in the world. As suggestive indices of the world, these documents work from a complex, referential network of texts and other maps, and digital tools need to be developed to study these networks. As J.B. Harley and David Woodward put it:
Cartographic history [has now become] the study of needs and wants rather than
of just the ability to make maps in the technical sense [...] it follows that the
capacity of cartography to influence actions or to mold mental worlds must depend
not only on the extent to which maps were actually seen but also on the way they,
or their messages, were understood. (508)
§ 7 All maps do not represent physical or culturally total
reality. Instead, maps are selective and highly inaccurate
representations of both explicit and tacit ideological ends (Wood and Krygier). With regards to the study of
medieval maps, it is time for the recognition of such differences to follow in
DM phase I development (2009-10)
§ 8 To realize a technological model for the genuine study of medieval maps, DM has proceeded on two fronts over its first two years of development: the generation of analyzable data from medieval maps and geographic texts, and the development of the architecture to make such generation and subsequent analysis possible. Using an early prototype of the DM annotation tool, the editing team under Foys annotated seven medieval maps and two geographic texts – the foundation for a small but representative sandbox of data.
§ 9 Maps:
- The Anglo-Saxon Cotton Map (British Library MS Cotton Tiberius B.V. f. 56v)
- A Higden Polychronicon Map (Corpus Christi College Cambridge [Parker Library], MS 21, f. 9r)
- The Thorney Map (Oxford- St. John’s College MS 17, f. 6r); the Sawley Map (Corpus Christi College Cambridge [Parker Library], MS 66, p.2)
- Matthew of Paris's Chronica Maiora Map of the Middle East (Corpus Christi College Cambridge [Parker Library], MS 26, f. 3v-4r)
- An unfinished late Anglo-Saxon mappamundi (Corpus Christi College Cambridge [Parker Library]; MS 265, p.210
- A mappamundi from Gunther Zainer’s 1472 printing of Isidore’s Etymologiae at section III ("De Asia") of Book XIV ("De Terra")
§ 10 Texts:
- Book One, Chapter Two of Orosius's Adversus Paganos Historiarum Libri Septem ("Seven Books Against the Pagans")
- Book One, Chapter One of the Old English Translation of Orosius's Adversus Paganos Historiarum Libri Septem ("Seven Books Against the Pagans")
§ 11 In addition, several other texts from the earlier EPPT phase (see section 2, above) await porting into the DM environment. All textual inscriptions and descriptions of locations on maps and in texts were recorded in XML (with coordinate locations for images and word placement for texts), along with accompanying descriptive data. These datasets, while relatively modest in size, provide excellent material through which to work out major issues of design and functionality. In addition, we now have robust data on which to build and through which to test our interface as the resource develops. The data may also serve as a framework model for subsequent users.
§ 12 During this phase, the programming team led by Bradshaw continued to developed early prototypes of editing and annotation resources. The earliest pre-alpha prototype was implemented in Adobe Flash and employed single coordinate-point visual tagging. Annotations were constrained to a custom set of XML descriptor tags and keywords (Figure 4). This phase I implementation of DM contained much of the basic functionality desired in such a resource (i.e. the ability to navigate and magnify an image of a map, tag and annotate specific areas, integrate annotations and include texts into a continuously extensible and searchable database, link directly from search results to precise locations on maps and text, and aid searches through incremental prompts). But a few months into development, the severe limitations of our approach became clear, in part due to the markedly variable and hybrid nature of the maps we were editing. While single-point coordinate editing worked well with limited graphical or textual detail on a map, it could not accommodate with necessary precision larger textual blocks that are found in documents like the Matthew of Paris map. Figure 5 shows a single-coordinate link from a search for a specific word in the Matthew of Paris map, which occurs within a much larger block of text. Short of creating a single-coordinate annotation for every single word in this target block (which would be cumbersome to both edit and view), editorial precision in this model was impossible. Additionally, mandating an exclusive one-to-one correspondence of target area to annotation denied the ability to link multiple moments of the map to the same annotation (without clunky redundancies in the data), or to precisely demark larger graphic or textual moments within the text. To paraphrase what one art historian said in response to an early presentation of DM: "That's great that you can tag that single-word inscription or a small iconic moment, but what if I wanted to annotate the whole oceanic circle that encompasses a map? How would I do that?"
§ 13 Our initial instinct to set fixed descriptive categories for
annotations (following the traditional logic of taxonomic structures for metadata)
was also problematic. At the beginning of our work, we approached annotation by
imagining discrete sets of tags that aimed to collectively cover all possible content
that medieval maps and related texts might contain (e.g. fields for inscription,
translation, keyword, figure, continent, quality categories [city, people, river,
mountain, etc.], and so forth), along with a search function that generated results
by polling one or more of these selected fields. Such a taxonomic approach is perhaps
most readily understood as analogous to the patterns of data annotation demanded by
such protocols as TEI, which imagines a prescriptive set of tag fields that can
comprehensively cover, in theory, any aspect of a text being marked up in XML. We
realized relatively early in development that there are considerable limitations to
such an approach, especially given the considerable variety of content found within
medieval maps. We also had no way to anticipate and then to accommodate the ways in
which future users might wish to annotate the materials we were editing, or how we
might keep our own prescriptive categories for annotation free from our own heuristic
bias. Such issues in annotation and editing led us to an acute
back-to-formula moment, and to a radical reworking of almost
every aspect of the resource to date, starting with a conceptual review of how
scholars do the work they do.
DM phase II development (2010-11): Scholarly primitives
§ 14 In re-designing a full-featured system to support scholarship on digital maps and manuscripts the DM-team first reconsidered the research practices of its user base. By this we mean the activities in which scholars engage when carrying a piece of work through from research question to publication. John Unsworth has identified a useful set of "scholarly primitives" that researchers commonly employ in their work: discovery, navigation, annotation, referencing, organizing, and comparison (Unsworth 2000). We have adapted these primitives as a basis for designing our new DM methods and tools, and as we engage with scholars about their research processes we have used this model to frame conversations about the full range of capabilities DM must embody. We address each primitive defined in this model below. Our intention is to provide a sense of the challenges inherent in each, rather than a comprehensive treatment. As such, this discussion reflects lessons learned to date and thoughts on future development for DM.
§ 15 Scholars engage in a variety of discovery tasks for the purpose of finding material necessary to their research. The example that usually leaps to mind is a Google-like search of a manuscript repository. Another is paging through manuscripts in search of folios of interest. But discovery processes may also include those that are less obvious in this context, such as encountering a previously unknown resource at the suggestion of a colleague. In light of this, we have identified at least two system requirements. The first is that DM must enable scholars both to access and annotate images available on-line to them, and to individually import images into the DM resource, as needed. This requirement causes a cascade of additional requirements to manage access, storage, and sharing of images (and will be the focus of a subsequent phase of our work). The second requirement is that in cases where scholars are unable to acquire electronic access to a map or manuscript existing in a digital repository, they must be able to incorporate that item into their annotations and overall work product as it develops within DM. This requirement has implications for most of the other scholarly primitives in our model.
§ 16 More generally, DM must support "social discovery" in a variety of forms. For example, scholars may wish to receive alerts about annotations others may make within DM on certain items or subjects. Likewise, annotations and other forms of content should each have a public URI so that they may be easily emailed, tweeted, and otherwise distributed. This raises the issue of public, private, and limited group annotations. For DM (or any other annotation resource deploying any social discovery tools) to develop to its full potential such concerns must be addressed, and will be the subject of future development and funding.
§ 17 Navigation is related to discovery, but focused on the many ways in which scholars move between resources, their notes, annotations, and other information linked to a research project. In designing for navigation, the challenge is in taking full advantage of the hypermedia environment to provide valuable navigation tools, while not adding complexity that confuses users of the system. Our objective is to ensure that from the point of viewing any piece of information in DM, the system enables scholars to take the next logical step along their research path and that the means of taking this step is obvious and natural. For example, in the view for a specific annotation, a well-defined navigation system will enable scholars to easily view related annotations or other appropriate information. It would also enable scholars to transition to natural follow-up tasks such as editing the annotation being viewed, generating a comment on that annotation, or sharing the annotation with a colleague.
§ 18 Annotation activity is one facet of this model that has received a great deal of attention among information scientists. Ancient manuscripts and related materials embody a form of information that is complex and varied in form. Furthermore, a given manuscript may be used in a wide variety of research projects. As a consequence, the DM annotation functionality must be flexible, enabling scholars to adapt it in ways we may not have envisioned (cf. the discussion on open taxonomies in section 4, above). As illustrated in detail in section 6, below, the current implementation of DM provides scholars with the ability to identify regions-of-interest by drawing points, segmented lines, and shapes (i.e. polygons) as overlays on images. In addition, scholars may write descriptive text and associate it with any number of images, regions-of-interest, other descriptive texts, or any other piece of information DM maintains. With further development, scholars will be able group such markers together in one or more layers in a manner much like lecturers once overlaid one overhead transparency on top of another. Our design principle here is to provide a handful of basic building blocks that scholars can assemble to suit their needs.
§ 19 Referencing in scholarly processes manifests itself in a variety of ways. The most common is in citing the publications of others in our own books and articles, and, increasingly, in on-line documents. As scholarship performed entirely in digital environments becomes more common, a number of other forms of reference will become important, such as citations to DM-like annotations within a book, article, or lecture. Other new forms of reference include the text of one annotation referencing annotations created by another scholar. Still further afield, one might use a video or imported image as a means of annotating (describing) a portion of a manuscript. Referencing is perhaps the least well understood primitive in our model because so many of the possible forms of reference we envision are not yet possible in a sustainable way. However, work in initiatives such as the Open Annotation Collaboration (OAC) is already beginning to consider the demands of referencing across a variety of media platforms, including image, sound and video. As DM develops, it will be well positioned to align itself within the new standards of referencing which emerge.
§ 20 Organizing is the task of applying a useful structure to the
materials of a particular project. Typically, scholars will use a number of
methods for organizing their research involving collections of notes, stacks of
papers, and other materials sorted into folders or in a filing cabinet. Designers
of information systems commonly remediate this arrangement, providing hierarchical
folders as means of enabling users to organize their documents. One of the
principal challenges in supporting the organizing primitive lies in enabling
scholars to structure their materials in an intuitive way, but one which also
exploits the advantages that a computer can provide over a physical filing
cabinet. In other words, users understand the filing cabinet metaphor immediately,
but remediating the filing cabinet as the only means of organizing resources
unnecessarily constrains the user. For example, even the most organized of
scholars will on occasion forget in which folder they placed a resource. For
others this is a problem faced daily. Furthermore, it is likely that some
resources, annotations, notes, etc., will be of use in many projects as scholars
follow a larger thread of inquiry. With a folder system, it is awkward to organize
materials to simultaneously be
part of multiple projects.
Therefore, questions such as the following arise. Is a formal organizing system
necessary? Would scholars be adequately served by tools that, at the point of
need, simply allowed them to filter their annotations, notes, etc., in various
ways (e.g. by keyword)? Would Web 2.0 tags be sufficient for organizing? How about
simple bookmarking or
liking resources and annotations of
others? Do we need all of the above plus hierarchical folders? Understanding how
best to support this primitive will, perhaps more than any other, require
extensive exploration of use cases and usability testing.
§ 21 Comparison is fundamental to many forms of research involving
medieval manuscripts. Examples abound in projects tracing many kinds of
relationships between texts. As with annotation, there are a wide variety of uses
for comparison. Therefore, it is probably best once again to employ a
building-block approach that will allow scholars to configure as needed the ways
in which they would like to view multiple images simultaneously for purposes of
comparison. As they work within a resource such as DM, scholars need
to be able to easily manage the
real estate of their work
area, as they arrange images and texts on screen. But much of the challenge in
supporting comparison also touches on other primitives such as annotation. For
example, in what ways do scholars need to be able to define relationships between
images? The comparison primitive also has implications for the primitives of
navigation and organization, because it is only possible to compare a small number
of images at once. Scholars must be enabled to organize materials they are
interested in comparing and navigate between them in a manner that is natural for
the study in which they are engaged.
§ 22 Each of the primitives we have summarized identifies a type of task scholars perform while engaged in research. In addition to the challenges inherent in supporting each task, we must also enable scholars to seamlessly switch from one task to another. When working with physical materials, scholars have the ability to lay them out on a desk. It is trivial to arrange resources and engage in comparison, annotation, and note-taking almost simultaneously. Likewise, locating other resources elsewhere on one's desk (navigation) and incorporating them into the comparison task requires little thought as to the mechanics of doing so. In general, when working with physical materials, scholars blend together most of these primitives, switching between tasks with little need to think about the transitions. Since the resources for a particular project are likely to be found in multiple repositories, providing a similarly frictionless workflow in a digital environment is a challenge that can only be fully met through cooperative technology (i.e. standards) developed through collaboration among repositories and tools developers. Some such projects are underway (Project Bamboo, DMSTech, and OAC).
DM phase II development (2010-11): Interoperability and breakaway tools
§ 23 With these primitives in mind, we have begun to explore how the tools being developed within DM might be applied to help break open the largely siloed nature of on-line repositories of digitized manuscripts. With funding from the Andrew W. Mellon Foundation, we worked with Stanford University's project team for the Parker Library on the Web project (PW) to study ways in which annotations manuscript images stored in PW could be created using DM tools, and then accessed and indicated in the PW interface through an interoperating protocol (Figures 6-7). The resulting successful test, where we were able to open up a Parker manuscript folio from PW inside DM, annotate it, and then have PW dynamically create an active link for those annotations on its resource display for that page, was an exciting proof of concept, pointing the way forward for how archival resources and scholarly tools in the digital realm can be designed to interoperate.
§ 24 In a move away from coordinate-only editing (see section 12, above), we developed a new architecture for
visual tagging, based on a tripartite approach of
(D-LISH). D-LISH was designed to provide maximum flexibility with regards to
annotators' graphic desires, providing them with the ability to more generally
indicate annotated areas on a map through single coordinate points, joining points of
significance lineally (either through traditional lines of text, or by connecting
horizontally disparate points [i.e. by
crooked lines]), or by
demarcating areas of annotation within user-generated polygonal spaces (Figures 8-9). Further, a single annotation could then
be grouped with any combination of multiple dots, lines and/or shapes. The result was
an image-selection tool that allowed for considerably greater choice in determining
what, exactly, was to be selected and annotated on an image than in pre-existing
tools for digital scholarship.
§ 25 At the same time that D-LISH was being developed, we radically shifted the direction of development with respect to models of annotation and search. Searches not only returned textual links, but visual correlatives and suggestions as well (Figure 9). We then focused on creating a completely open mode of annotation, where users simply enter annotations as untagged text, with the option to designate individual terms as prioritized keywords, through the use of a hash (#) tag. Such annotation cannot really be considered purely folksonomic, though it does retain the capacity for such tagging if desired by the user. In response to such a simpler, open-form annotation model, the development of our search algorithm has become substantially more complicated, as the work of parsing annotated material will have to be handled by the search, not the annotation function. In the end, however, this model will result in a substantially more agile and dynamic response for end users wishing to search a growing set of both materials and annotation.
§ 26 To support this new functionality and future interoperability, the backend database was redesigned and rebuilt with a more general data model. This model enables us to easily accommodate data in the Open Annotation Collaboration (OAC) protocol, which is emerging as an interoperability standard among large repository and tools initiatives underway at Stanford University, Johns Hopkins University, the University of Toronto, and the University of Maryland, among others. As a second step toward a broadly usable resource, we have exposed DM's annotation repository through a web services framework. The web service enables client systems (including our own) to search our annotation repository using an expressive query language and sophisticated search metrics. The search system is based on Solr from Apache's Lucene project. Clients may search the repository using raw search terms, faceted search by user-defined field, or more complex techniques such as more-like-this queries. Client systems may also mine or store annotation data by pulling or pushing XML feeds of layered annotations for any map in our dataset. Clients may also constrain annotation data feeds by proximity to a location on an image, by annotating user, by timestamp, and a variety of other metrics. Additionally, external URI links to specific coordinates and annotations may be generated.
§ 27 In rebuilding the front end, we moved from a Flash-based
interface, we were careful to develop toward an open-source library that enables
widespread adoption. At the end of Phase 2 development, DM had an alpha version of a
set of tools that enabled scholars to mark regions-of-interest within images and
associate textual annotations with those regions. Scholars may mark images with
individual points, segmented lines, or custom polygonal shapes. Significantly, a
scholar may identify any number of markers on any number of images as the targets for
textual annotation. Additionally, a given marker may serve as the target for any
number of textual annotations. Finally, scholars may organize their annotations into
layers so that different research questions
involving a single image may be addressed separately through annotation. Scholars may
choose to view a single layer of annotation or view multiple layers of annotation
overlaid on one another.
§ 28 In 2012, the DM environment is in beta development, and working with a series of projects covering a wide range of digitized medieval materials. The Dictionary of Old English (DOE) project, for example, is using DM to annotate and link examples of Old English words from on-line manuscript collections to individual DOE entries. The Parker’s Scribes project at the University of Toronto and Oxford University annotating examples of sixteenth-century marginal notations from the Parker on the Web digital repository of medieval manuscripts and creating precisely linked data to be rolled out as an on-line resource. Individual scholars are also using DM: Lisa Fagin Davis is digitally annotating all of the content on a Chronique anonyme universelle -- a 50-foot-long historical and genealogical scroll with over 1,500 individual figures and events depicted for creation of an electronic edition to accompany a forthcoming academic publication for Brepols. And in his Insular and Anglo-Saxon Illuminated Manuscripts: An Iconographic Database project, Asa Mittman and his team is using DM to take Thomas Ohlgren's 1986 print "database" of 229 codices accounting for nearly all visual iconography in Anglo-Saxon manuscripts and turn it in to a linked, digital environment that will dynamically import images from on-line digital manuscript repositories. Finally, the original medieval maps project has grown to an institutional partnership, and become the Virtual Mappa Project (VMP), by which British Library and Foys will use DM to design and publish an on-line collection of historic maps that multiple groups may use to create linked environments of annotations for individual, collaborative, and instructional purposes. Once VMP is implemented, the British Library will then be able to partner with other institutions to augment this resource, fashioning a virtual collection that allows for true repository interoperability and the potential for deep public, educational and scholarly interaction. For a full overview of current DM functionality, as well as of projects using DM, please see http://ada.drew.edu/dmproject/
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