The Digital Artifact in Library Collections


John Unsworth

Task Force on the Artifact in Library Collections

Council on Library And Information Resources




Library Collections vs. Archives


“The functional chain of the different forms of linguistic representation is of great importance for those libraries and archives, whose duty it is to safeguard society's ability to recall its past. Whereas libraries are more concerned with keeping up knowledge and making it available, archives guarantee the availability of earlier experience. Both fields, however, employ the stabilisation and concrete form of the content of library and archive material in order to make it available.”  [Menne-Haritz, “the effect of digital representation” in “The Intrinsic Value of Archive and Library Material”]


The two key terms in this passage are “stabilisation and concrete form.”  For libraries, “concerned with keeping up knowledge and making it available,” stability and concrete form are important because they make long-term preservation and access economically feasible.  For archives—the institutions that “guarantee the availability of earlier experience” not only in the sense that libraries do, but also in the sense of establishing the chain of evidence—stability and concrete form are also important because they are absolute requirements for proving the authenticity and provenance of unique documents.  Of course, libraries also need to be able to assure the scholars who use their materials that those materials are what they purport to be, and that they can be used as evidence (albeit for scholarly arguments, rather than legal ones). 


Our concern, in this document, is principally with library collections rather than archives—but many of the strategic issues and decisions provoked by the presence of digital artifacts are common to both.  In fact, in dealing with the problem of digital artifacts, collections development personnel in libraries stand to benefit from considering one basic principle and one questionable opposition of long standing in the archival community.



Intrinsic vs. Fungible Value


The distinction between the evidence inherent in original forms and the information that can be abstracted from them—important to both libraries and archives, though perhaps in different ways—emerges from early preservation efforts:


“Among the many early archives and historical organizations that sought to preserve their materials by publishing and diffusing them, there developed a surprisingly modern distinction between the permanence of the archival documents themselves and the permanence of the information they contained.  Initially, historical collections were valued principally for their information, information that testified to the ‘pastness of the past’ and thereby certified ‘the reality of progress.’  Only later did repositories come to value their collections as things worthy in their own right and, later still, as sources for specialized study by professional scholars.” (O’Toole, 16-17)


“Intrinsic value” is the name now used by archivists for the value of “things worthy in their own right,” and it also names the principle used in deciding when historical materials must be retained in their original form and when they can be represented with copies.  The distinction is important in connection with digital artifacts in library collections not only because it would be relevant to deciding what can be represented by a digital surrogate rather than retained in its original form—or, less drastically, when a digital surrogate will suffice in place of access to an original still retained by the library—but also because it might help libraries to sort out what features of the born-digital artifact are unique to the original form of that artifact and what could be carried forward without loss into new incarnations.  Intrinsic value, then,


“…is the archival term that is applied to permanently valuable records that have qualities and characteristics that make the records in their original physical form the only archivally acceptable form for preservation.  Although all records in their original physical form have qualities and characteristics that would not be preserved in copies, records with intrinsic value have them to such a significant degree that the originals must be saved.”


The qualities and characteristics of records with intrinsic value are enumerated in this 1982 Staff Information Paper from the National Archives and Records Service as follows:


  1. Physical form that may be the subject for study if the records provide meaningful documentation or significant examples of the form….
  2. Aesthetic or artistic quality….
  3. Unique or curious physical features….
  4. Age that provides a quality of uniqueness….
  5. Value for use in exhibits….
  6. Questionable authenticity, date, author, or other characteristic that is significant and ascertainable by physical examination….
  7. General and substantial public interest because of direct association with famous or historically significant people, places, things, issues, or events….
  8. Significance as documentation of the establishment or continuing legal basis of an agency or institution….
  9. Significance as documentation of the formulation of policy at the highest executive levels when the policy has significance and broad effect throughout or beyond the agency or institution….

(“Intrinsic Value in Archival Material” 1)


The test of intrinsic value is that it can only be carried by the original document itself—even though, according to this statement of criteria, characteristics establishing a document’s intrinsic value may be either “physical or intellectual: that is, they may relate to the physical base of the record and the means by which information is recorded on it or they may relate to the information contained in the record.”  So, although “intrinsic value” may be determined by something external to “the physical base of the record,” it is clear that the opposite term for ‘intrinsic value’ is not, as one might think, ‘extrinsic value’ but rather ‘fungible value’—in other words, a value which can be represented by a substitute form, or a value which can be transmitted without loss across forms.   And finally, according to the same study, the judgment of this intrinsic value is, inevitably, a relative rather than an absolute evaluation:


“Records that possess any characteristic or quality of intrinsic value should be retained in their original form if possible.  The concept of intrinsic value, therefore, is not relative.  However, application of the concept of intrinsic value is relative; opinions concerning whether records have intrinsic value may vary from archivist to archivist and from one generation of archivists to another.  Professional archival judgment, therefore, must be exercised in all decisions concerning intrinsic value.”  (“Intrinsic Value in Archival Material” 2-3)


Almost by definition, of course, library collections do not consist of materials that have intrinsic value, in archival terms—the books, journals, and newspapers in the stacks and in circulation are not unique (many other libraries have copies of the same items), their physical form is not especially important (usually physical form is not even intact, as items are routinely rebound so they can stand up to heavy use), they are not so old as to be especially valuable, and so on.  But as Nicholson Baker’s recent diatribe (“Deadline”) on the de-accessioning of newspaper collections demonstrates, the question of whether intrinsic value inheres in such materials is open to debate, and therefore, the criteria listed above are relevant for at least two reasons.  First, as we begin to digitize library collections, we need to consider whether there are, in fact, important features or uses of those collections that are not fungible—otherwise we can never be sure when it will be acceptable to replace physical collections with digital surrogates, nor even what uses of the physical objects might be replaced by uses of a digital surrogate.  Second, even though libraries may not bear the burden of legal proof that archives do, it is still important to scholars to know the source, provenance, and authority of the evidence they find in libraries.  Moreover, as libraries begin to acquire artifacts that are originally digital, the criteria of intrinsic value will help us to understand where these artifacts need special authentication and documentation, where our technologies for producing, collecting, and transmitting them need further development—they might even help us to understand when the digital artifact is not simply a collection of bits, but also must include (and not merely emulate) original hardware and software (with all the practical difficulties and complex dependencies that such an object would entail).



Preservation vs. Access


The questionable distinction (and sometime opposition) between preservation and access may also be of some use in understanding how to deal with digital artifacts in library collections.  This opposition—based on the commonsensical observation that there is an inverse relationship between use and longevity—is an old one: 


“One historical society in Ohio in the 1840s announced its intention ‘to preserve the manuscripts of the present day to the remotest ages of posterity,’ adding almost theologically, ‘or at least . . . as near forever as the power and sagacity of man will effect.’  To accomplish this it proposed to store its manuscript and archival holding in ‘air-tight metallic cases, regularly numbered and indexed, so that it may be known what is contained in each case without opening it.’” (O’Toole, 15)


Even now, there are clear cases where cold storage (literal or figurative) is the best way to preserve an artifact with intrinsic value—photographic negatives, for example, or rare manuscripts.  In the case of born-digital artifacts, though, another interesting possibility or principle suggests itself, namely preservation through handling:


“[E]lectronic resources require funding, skill, and ongoing commitment. Those that are intended for permanent use, moreover, will almost certainly require repeated intervention to ensure that they remain viable as technologies evolve.” (Hazen)


Precisely because the technologies used to encode, display, and enact digital information are changing so rapidly, the digital artifact that goes untouched for ten or twenty years may well be unrecoverable—because its storage medium requires hardware that no longer exists, or the software used to create it can no longer be found, or the operating system under which that software ran is obsolete, and so on.  Even if none of those problems prevent access to the artifact, there is still the problem of the ephemerality of the artifact itself:  as O’Toole points out, “by almost any standard, virtually all of the newer means of recording information, though more flexible, are less permanent than older ones”  (25). 


There’s a good deal of literature on the need to refresh and migrate digital information in order to keep it available for use (see in particular “Preserving Digital Information: Report of the Task Force on Archiving of Digital Information”).  Migration—the process of moving digital information out of old formats and into new ones—raises all the core issues of intrinsic value, and there have been some interesting responses to that problem (e.g., Clifford Lynch’s “Canonicalization: A Fundamental Tool to Facilitate Preservation and Management of Digital Information”).


But whether or not we believe that digital artifacts have intrinsic value, and whether or not we believe—if they do—that this value can be retained as we migrate them across generations of carrier media and data formats, it is still clear that, where the value in digital artifacts is fungible, frequent handling may be the best assurance that this value will survive. 



Two Kinds of Digital Artifacts


In library collections, one finds two kinds of digital artifacts: originals and surrogates.


Digital originals are less common, and the term itself is more problematic, for although “original” implies uniqueness, digital information is, by its nature, perfectly replicable.  Nevertheless, it is clear that library collections now contain materials that come into being in digital form and are not surrogates for physical objects.  This category of materials would include things like the Inter-university Consortium for Political and Social Research (ICPSR) data sets (which collectively comprise the world's largest archive of computerized social science data), or the Environmental Systems Research Institute (ESRI) data and maps (a detailed set of data for the US and the world, including census boundaries and major transportation features), or—increasingly—thematic research collections (e.g., Ed Ayers’ Valley of the Shadow civil war site or Columbia International Affairs Online) created by scholars and/or publishers. 


Digital surrogates stand for original artifacts of some kind—usually, at this point, artifacts that concurrently exist, or previously existed, in another form (typically, but not necessarily, physical), either as part of the library’s collection or as part of some other collection.  Digital page images are a very common example of digital surrogates: audio and video digitized from analog sources would be other examples.  But we can also already point to digital surrogates for digital originals—for example, when texts marked up in the Text Encoding Initiative (TEI) Document Type Definition (DTD) are transformed into, and delivered in, the HTML (HyperText Markup Language) DTD, or when GIS (Geographic Information Systems) data are delivered as JPEG (Joint Photographic Experts Group) images. 



Digital Originals


When considering artifacts that are originally digital, the first and possibly the most difficult question is, “what is the artifact?”  What information or value inheres in the carrier medium?  Is the equipment originally used for display part of the digital artifact? Does the software that presents and actualizes the data qualify as a constituent element of the artifact as well?  Thinking again of the criteria for determining intrinsic value in an artifact—as a way of understanding what the features of an artifact might be—we can see a number of very practical ways in which these vexed questions might surface:


Physical form that may be the subject for study if the records provide meaningful documentation or significant examples of the form:  For example, the layout of a form used for collecting data on the Web (software) might have a good deal to tell us about otherwise inexplicable aberrations, omissions, or misconstructions in the data collected. 


Aesthetic or artistic quality:  A member of this task force writes: “I may wish to read or use information in a form that recreates the context in which it was originally created or used.  This will mean running a program on originally specified system hardware and software.  Members of the committee are welcome to visit my office and play a really awful all-ASCII version of PacMan on my 1984 Kaypro II:  the experience cannot be replicated otherwise” (Jim O’Donnell).  This is asserted in spite of the existence (at of software emulation (in Java) that allows one to run Kaypro (Z-80/CPM-based) software on contemporary (Intel/Windows-based) systems.  Presumably, the physical attributes of the Kaypro’s Keytronic keyboard, its 9-inch, 80-character by 24-line green phosphor display screen, its clunking 5.25” 191K disk drives, etc., are part of a genuine aesthetic experience.   In fact, this same example—the complex artifact that is the Kaypro II plus its operating system and applications software—could probably also serve to illustrate the criteria of unique or curious physical features  (this 26-pound computer was an early (1983) example of the “portable” computer, designed originally for field use by engineers, with no sound or graphics capability—hence the curiosity of an ASCII PacMan) as well as age that provides a quality of uniqueness and value for use in exhibits (given the rapidity with which “generations” of computer technology pass, and the average user’s tendency to discard outmoded equipment).


An exhaustive set of examples is not necessary here—these few suffice to show that the relevant features of a digital artifact could include more than the fungible information contained in an electronic file.  Arguably, though, the Kaypro II belongs in an archive, not a library, for precisely the reasons just given.  For the library, it might be enough to have a photorealistic 3D virtual representation of the Kaypro, and perhaps an emulation package that allows a researcher to run the original CPM code on current hardware.  And though the Kaypro example may seem facetious, these are in fact be the sort of questions that library collections development staff will be asking themselves, as they grapple with the problem of collecting born-digital information. 


In many cases, the answer for libraries will be that they are, in fact, primarily concerned with collecting, preserving, and providing access to the fungible informational content of digital objects.  In that case, the “preservation through handling” scheme is a likely winner: digital information that is frequently used by library patrons undoubtedly stands a better chance of being migrated and refreshed, and therefore is more likely to continue to be available in future generations, compared with little-used digital information.  Indeed, migration may turn out to be a much more frequently recurring problem than refreshing, because “today’s optical media most likely will far outlast the capability of systems to retrieve and interpret the data stored on them”  (Conway in Handbook for Digital Projects).  That’s bad news for libraries, since it is easier and cheaper to refresh than to migrate.  If libraries have reason to be hopeful, in this regard, it lies in open, non-proprietary, standards such as JPEG for images, MPEG for video, and SGML, XML, and XSL for textual data.  There are still important data types for which no such standards exist (GIS data, for example), but the trend over the last twenty years—accelerated significantly in the last decade by the advent of the World-Wide Web—has been in the direction of support for non-proprietary standards, even in proprietary software.  The furthest extreme of standards-based optimism, in this regard, is represented by a recent contribution to D-Lib Magazine by a group of supercomputing scientists (Reagan Moore et al.), who believe that we can devise “an approach for maintaining digital data for hundreds of years through development of an environment that supports migration of collections onto new software systems.” (“Collection-Based Persistent Digital Archives - Part 1”). 


Even those not willing to go quite so far in predicting success might look seriously at another promising strategy, called LOCKSS (Lots of Copies Keep Stuff Safe).  The basic principle of LOCKSS is preservation through proliferation.  LOCKSS is


“a network of PCs based at libraries around the world and designed to preserve access to scientific journals that are published on the web. The computers organise polls among themselves to find out whether files on their hard disks have been corrupted or altered, and replace them with intact copies if necessary” (“Here, There and Everywhere,” The Economist, June 24th, 2000). 


This is actually an old idea, one that goes back to the 18th century:


“I learn with great satisfaction that you are about committing to the press the valuable historical and State papers you have been so long collecting. Time and accident are committing daily havoc on the originals deposited in our public offices. The late war has done the work of centuries in this business. The last cannot be recovered, but let us save what remains; not by vaults and locks which fence them from the public eye and use in consigning them to the waste of time, but by such a multiplication of copies, as shall place them beyond the reach of accident.”  (Thomas Jefferson To Ebenezer Hazard, Philadelphia, February 18, 1791, in Jefferson’s Letters).


And though, with manuscript originals, the “preservation through proliferation” strategy assumes that a surrogate is adequate (that the value of the artifact is fungible, and that it is the information, and not the artifact itself, that one wants to preserve), with digital originals, one might well use the same strategy to preserve digital artifacts in their original form (while recognizing that a million perfect copies will still stand mute if we no longer understand how to read them). 


Digital Surrogates


The most common digital kind of digital artifact in library collections today is the digital surrogate for a physical artifact.   For that reason, the most important questions about digital artifacts, at the moment, are questions having to do with this kind of digital artifact.  Chief among those questions are:


·        When can a digital surrogate stand in for its source? 


·        When can a digital surrogate replace its source?


·        When might a digital surrogate be superior to its source?


·        What is the cost of producing and maintaining digital surrogates?


·        What risks do digital surrogates pose?


Many of these questions are treated in some detail in Paul Conway’s contribution to a recent publication of the Northeast Document Conservation Center, the Handbook for Digital Projects: A Management Tool for Preservation and Access:


“The Preservation Purposes of the Digital Product [include efforts to] …. Protect Originals …. Represent Originals …. [and] Transcend Originals…. In a very small but increasing number of applications, digital imaging holds the promise of generating a product that can be used for purposes that are impossible to achieve with the original sources.  This category includes imaging that uses special lighting to draw out details obscured by age, use, and environmental damage; imaging that makes use of specialized photographic intermediates; or imaging of such high resolution that the study of artifactual characteristics is possible.”  (“Overview: Rationale for Digitization and Preservation”)


Conway makes clear the promise of the digital surrogate.  The risk posed by these surrogates is presented in Menne-Haritz et al., “The Intrinsic Value of Archive and Library Material”:


“the loss of testimony is endangered, not only through . . . physical degeneration . . . but also through the unconscious destruction of evidence as to the context and circumstances of their origin, which can occur during their conversion and must therefore be prevented by a previous analysis of . . . intrinsic value.” 


The problem to which Menne-Haritz adverts is not unique to digital surrogates, by any means: bad editions in printed form pose the same threat, and indeed the early history of printing is, in part, a history of the loss or destruction of manuscript materials “replaced” by printed versions—the sources for which are now both undocumented and unrecoverable.  In any case, this German archivist presents the most reductive view of the value of digital surrogates, saying


“The loss of evidential value and permanent accessibility inherent in digital forms and textual conversion [by OCR] exclude them as a preservation medium.  They can only be employed in addition to preservation on film in order to increase the ease of use,”  (“The necessity of criteria for conversion procedures” in “The Intrinsic Value of Archive and Library Material”)


and, at another point, flatly stating that:


“digital imaging is not suitable for permanent storage.”  (“Imaging” in “The Intrinsic Value of Archive and Library Material.”)


A preservation program based entirely on film, with digital surrogates used only for distribution of photographic images, may not be practical in all cases, though—and it is at this point that we must confront the differing missions of libraries and archives.  Archives may well decide that issues of evidential value rule out “digital forms and textual conversion,” whereas libraries might reasonably feel, in certain cases, that their mission of preserving and providing access to (fungible) information is adequately served by providing digital surrogates. 


In fact, it is probably impossible to give a single answer to the question “What is the utility of a digital surrogate?” since the answer depends, to a large extent, on the nature of the original and the conditions of its use. Therefore, as a means of determining the value and appropriate use of digital surrogates for library holdings, it may be useful to divide the original materials into those that are rare and those that are not, and to divide them further into those that are frequently used and those that are infrequently used.  There would be, then, four possible cases:


1. Materials that are not rare and that are frequently used:


In this case, we can assume that preservation of the original is not a particularly high priority (since the original is not rare); nevertheless, digital surrogates for such an object might be worth producing and providing, for several reasons:


·        To reduce the cost associated with reshelving the object

·        To make the object simultaneously available to multiple users (for example, through an electronic reserve desk)

·        To replace the object, thereby doing away with the cost of housing it.


The first two are obvious and uncontroversial benefits.  The third is potentially problematic, even if the object in question is not rare, because it is not obvious that digital surrogates provide all the functionality, all the information, or all the aesthetic value of originals.  Therefore, while it may be sensible to recommend that digital surrogates be used to reduce the cost and increase the availability of library holdings that circulate frequently, the decision to deaccession a physical object in library collections and replace it with a digital surrogate should be based on a careful assessment of the way in which the original object (or objects of its kind) are used by library patrons.  It is not necessary that the digital surrogate possess all the qualities and perform all the functions of the (not rare) original, but it is necessary that the digital surrogate answer to the identifiable needs and expectations of those who frequently used the original.


2. Materials that are not rare and that are infrequently used:


Many libraries now store infrequently used books (and other materials) in long-term storage facilities.  Those materials are retrievable and available to library patrons, but only after a wait of two or three days.  With such materials, digital surrogates might:


·        help users to determine whether recalling an object from long-term storage was worth the wait—and worth the library’s effort

·        increase frequency of  use (by providing searchable metadata, for example)

·        reduce costs by replacing the object with a digital surrogate.


Again, the first two are obvious and uncontroversial benefits, and the third comes with the caveat, as in 1., that the digital surrogate should answer to the identifiable needs and expectations of those who (in)frequently used the original.  At some point, of course, especially with infrequently used materials that are not rare, libraries might reasonably be expected to evolve a calculus that balances functionality with actual use, in order to help decide when digital surrogates that provide most of the functionality of originals are acceptable.


There is one other point that needs to be raised, especially here, where we are discussing the component of library collections that has the least “market value.”  Libraries, as an institutional and cultural community, need to consider whether these infrequently used and commonly held materials are, in fact, being preserved in a concerted and deliberate way in their original form by any one (or more than one) library.  If they are not, the sources for digital surrogates that are common today could easily become rare, or non-existent, tomorrow.  This is the substance of Nicholson Baker’s objection to libraries discarding their newspaper holdings.  If there are fifty libraries that hold the same issues of the same newspapers in original form, at great expense and with limited use, then it is difficult to make the case that all of them should pay to house, shelve, reshelve, and preserve the originals, but if forty-nine of those libraries, over time, have replaced their physical holdings with digital surrogates, one certainly hopes that the fiftieth library would be aware that its physical holdings were now rare, and therefore subject to considerations outlined in cases 3 and 4, below. 


3. Materials that are rare and are frequently used:


In this case, the principal (and very obvious) benefits of digital surrogates are:


·        Preservation:  by standing in for some uses, the digital surrogate reduces wear and tear on the original object.

·        Access: by providing access that doesn’t impose wear and tear on the original, the digital surrogate makes rare objects more accessible.


Few would argue that truly rare materials should be replaced by digital surrogates: digital technology, and techniques of digitization, are so new, and are still developing so rapidly, that we can’t have any confidence we’ve devised the best method for extracting and digitally representing information from any analog source (whether it is a printed page, an audio tape, or a film strip).  Nonetheless, digital surrogates could, in many cases, stand in for rare and frequently used materials, and could thereby aid in the preservation of originals. 


4. Materials that are rare and are infrequently used:


On the face of it, these materials seem the least likely to be represented with digital surrogates, if only because digitizing is expensive.  On the other hand, if the cost of housing a rare but infrequently used object rises high enough, then digitizing and deaccessioning that object may become an attractive possibility.  Here again, as in 2, above, one hopes that libraries, as a community, are aware of the lastness, the actual or potential rarity, of even those materials used infrequently today.  Tomorrow, those may very well be the most valuable of artifacts, perhaps for users, or uses, that one could not predict today.


Having considered this quaternion of conditions, let us revisit the questions with which we opened this discussion of digital surrogates, and try now to provide some answers to those questions:


·        When can a digital surrogate stand in for its source? 


When it answers to the needs of users.


·        When can a digital surrogate replace its source?


If the source is not rare.


·        When might a digital surrogate be superior to its source?


In cases where remote or simultaneous access to the object is required, or when software provides tools that allow something more or different than physical examination.  When the record of the digital surrogate finds its way into indexes and search engines that would never find the physical original.


·        What is the cost of producing and maintaining digital surrogates?


The cost of producing digital surrogates probably depends on the uniformity, disposability, and legibility of the original.  The cost of maintenance depends on frequency of use and the idiosyncracy of format, but beyond that it depends on technological, social, and institutional factors that are difficult or impossible to predict—which is an important reason for being cautious when one chooses to replace a physical object (the maintenance costs for which are known) with a digital surrogate (the maintenance costs for which are, to some extent, unknown). 


·        What risks do digital surrogates pose?


The principal risk posed by digital surrogates is the risk of disposing of an imperfectly represented original because one believes the digital surrogate to be a perfect substitute for it.  Digital surrogates also pose the risk of providing a partial view (of an object) that seems to be complete, and the risk of decontextualization—the possibility that the digital surrogate will become detached from some context that is important to understanding what it is, and will be received and understood in the absence of that context. 




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Baker, Nicholson. “Deadline: A desperate plea to stop the trashing of America's historic newspapers.”  The New Yorker, July 24, 2000, 42-61.


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Jefferson, Thomas.  Letters, ed. Merrill D. Peterson, Literary Classics of the United States, Library of America Series, New York, 1984.


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