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Scientific Examination of Art: Modern Techniques in Conservation and Analysis (2005)

Chapter: The State of the Field - Overview--John Winter

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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
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The State of the Field

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
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Overview

John Winter

Freer Gallery of Art and Arthur M. Sackler Gallery

Smithsonian Institution

Washington, D.C.


This paper introduced a colloquium whose theme was the study of works of art by scientific methods. To present a brief overview of a field where all kinds of works might be studied by any applicable kind of scientific technique is hardly a practical possibility. Rather, I would like to try to give a little more depth to all of this, in terms of both the history and the diversity to be found in studies of these types.

One basic problem lies in the conceptual magnitude and diversity of such a field. A “work of art” can mean a human artifact designated as such and made from an enormous variety of materials. Implicitly we are attempting to bring together objects made from rocks and minerals, metals of all kinds, ceramics, organic materials derived from plants and animals, or synthetically created—the list goes on. An artifact may be a complex, partially ordered system with components of diverse chemical nature, as is true of most paintings and many other things, or it may comprise only one type of component. The scale can vary from thumbnail size to that of architecture and monuments. Even the word “art” does not help much, since any familiarity with the field reveals people working with what is usually termed self-conscious art, with decorative art, or with functional objects regarded for the purpose as art. For the most part, scientists who choose to do this kind of research do not seem to trouble themselves overmuch with how artistic the art is. The field overlaps that of archaeological science, which studies archaeological, usually excavated artifacts, although much archaeological science is not concerned with artifacts at all. All these things might be examined using any method from any branch of science that holds the promise of yielding some kind of result. This colloquium will be covering large segments of this whole area,

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

though it would be optimistic to suppose that all possible types of work and kinds of artifacts could possibly be covered in two days.

PEOPLE

A word should be entered concerning the scientists who choose to do this kind of work and where they do it. The field can scarcely be said to be overpopulated by practitioners, at least in relation to its overall conceptual scale. Tennent (1997) saw the organizational structure as being in four parts: laboratories in museums, those university departments that take an interest, research institutes (often national research institutes) that have departments established for this purpose, and to a lesser extent the private sector. Many people in the field nowadays are professional research scientists fully committed to this branch of research in the same sense that other scientists will consider themselves fully committed to a particular branch of science. These tend to be found working in the research institutes and in departments of the larger museums, occasionally in universities. The majority of them are scientists who started out in some branch of the mainstream sciences, typically a branch of chemistry or physics or materials science, before moving into the present field. There are now a few, though only a few, who were able to do graduate studies in the field itself. A smaller group of research scientists have their primary interests elsewhere but also take part in cultural properties studies. They tend to be in academic institutions and may work on projects of interest for a short or extended period and then move out of the field again. Then there is a less easily defined group of scholars and professionals who are trained in fields other than the sciences but who perform and apply research to problems in their own field: art historians, conservators, and archaeologists may fall into this category.

Most major branches of physical science have much higher numbers of researchers than is the case with us, and modern science has as a consequence a considerable social structure, for want of a better term. Leading scientists form groups and schools of research that interact with one another, perhaps in collaboration, perhaps in competition. This can be on a relatively large scale and may sometimes last for extended periods. It includes direct, informal contact as well as more formalized kinds. In our field this intensity of interaction, which depends on a kind of critical mass of people, is much less. The number of practicing researchers is too small in relation to the number of kinds of things that they might be doing, that is the number and variety of research topics that exist. Since it is at least arguable that the immense success of the twentieth-century scientific endeavor in general was to some extent a result of such social structuring, problems are implied for our own comparatively diluted areas for which it might be difficult to find answers.

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

TECHNIQUES AND TERMINOLOGY

The scientific methods that we use deserve some comment, though it is difficult to generalize. They have usually been methods of study—of analysis, imaging, accelerated testing, and so forth—taken quite directly from other areas of science and technology. They tend, as a result, to have been optimized for work within some other field. With a few important exceptions, such as one or two dating methods, most techniques were not developed specifically within our own field. This state of affairs, of a conceptually large research field populated by relatively small numbers of researchers using techniques borrowed from elsewhere, led one colleague, Irwin Scollar, (actually with reference to archaeological science) to suggest that this was equivalent to conducting guerrilla warfare using captured weapons (Olin, 1982, p. 102).

One of the consequences of the rather complex situation that I have just sketched is terminological: There is no general agreement on what to call this field of study, taken as a whole. There is not even total agreement on what general term to use for the objects of study. Since they may or may not be archaeological, may or may not be historical, and may or may not always be artistic (according to somebody’s definition), such phrases as “cultural heritage,” “cultural property,” and “cultural assets” have come into use but are clumsy when an extension of the terms into studies using scientific methods is required. For the field of study itself we have on the archaeological side, “archaeometry,” “archaeological science,” and “science in archaeology,” which have all been used, and sometimes criticized. These terms are not usually extended to research on works of artistic or historical importance unrelated to archaeology. Here “conservation science” has become prevalent, especially in the United States, though the work may or may not be related to efforts to conserve the objects concerned. “Technical studies of works of art” was in use in the 1930s but is seldom found now. “Technical art history” has appeared, and the parallel to archaeological science would appear to be “art historical science.” All these terms, however, seem to imply subsets of the field as a whole, which awaits its definitive title and therefore perhaps its precise definition.

HISTORY

It might help give some depth to the discussions to look briefly at the history of the field. Even an extended look would be partial, since to the best of my knowledge no definitive account is available: Much of the historical spadework remains to be done. We do know that scientific study of antiquities and works of art goes back to the late eighteenth century. Earle Caley (1951) located almost 100 publications dated before 1875 (of which the earliest was late eighteenth century) mostly concerned with archaeological materials, and especially with the analysis of metals. Through the nineteenth century, work on this kind of material was

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

sporadic and mostly conducted by a few individuals concerned with identifying and analyzing archaeological and similar material on the side in laboratories primarily devoted to other purposes. Thus were the origins of one kind of research that continues to the present day: the study of artifacts that we consider archaeological, whether or not systematically excavated. It is now regarded as one segment of archaeological science, the segment concerned with artifacts. Much of this research seems to be done in academic institutions. The driving force is largely archaeological, and although the objects concerned may also be classified as fine art, this is largely coincidental. There is typically freedom to take samples necessary for analysis, and conservation of the objects has not usually been an issue. We might regard this as the archaeological tributary of the research efforts that developed during the twentieth century.

The examination of paintings and sculpture appears to go back over a similar time period. Since this paper was delivered, Nadolny (2003) has published a historical study of early analytical work on paintings, which appears to date from ca 1780. We know of analyses of pigments in mural painting by Haslam in 1800 and Humphrey Davy in 1815 (Rees-Jones, 1990), and of work in Munich on easel paintings from 1825 (Miller, 1998). It can be regarded as forming another line of development leading to where we are now. Two of the better-known practitioners were A. H. Church in the late nineteenth century and A. P. Laurie in the earlier part of the twentieth century; both served as professors at the Royal Academy of Arts in London. Much of the motivation for this type of work seems to have been historical interest, with reference being made also to various historical texts. Both connoisseurship and a desire to encourage contemporary artists to use appropriate and durable materials may also have played a part. This kind of research seems mostly to have taken place in the larger museums and in research institutes set up to work with them, occasionally in academic departments. Here conservation of the object is much more of an issue; the taking of samples is more restricted, especially in recent times, and may be forbidden outright. Consequently noninvasive methods have become important.

Scientific research devoted to making conservation itself more rational and effective came along a little later than the preceding two tributaries of development, though it can also be traced back to the nineteenth century. The National Gallery in London commissioned reports on the condition of its paintings in the 1850s (Brommelle, 1956), and the British Museum consulted outside scientists on conservation problems well before setting up its own facilities (Watkins, 1997). In 1888 Friedrich Rathgen’s laboratory was set up in the Königlichen Museen in Berlin (Plenderleith, 1998). The years following the First World War saw the founding of conservation departments in a number of places: the British Museum and the National Gallery in London, Le Louvre in Paris, the Fogg Museum at Harvard University, among others. This kind of research has come to overlap extensively the research in the preceding category, the historical investigation of

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

the fine arts. It tends to be done in similar places and often by the same people, and similar restrictions on methods of investigating an object usually apply.

There is much complexity in the ways that these historical streams have flowed down to contribute to the present state of affairs. There is overlap of major categories, both conceptually and in the sense that the same people may conduct kinds of research that might be looked upon as logically different. Different classes of cultural property also impose their own characteristics on any studies that are conducted on them. Research on large-scale entities (for example, buildings, monuments, and sites) is probably driven very largely by conservation needs, including protection and restoration, but its practitioners might see little in common with the conservation of museum objects.

AESTHETIC CONSIDERATIONS

Given this complexity in the study of anything held to be of cultural significance, using many techniques from the sciences, with a number of reasons and motivations driving us, what are the common threads? What kind of conceptual framework is it possible to discern in all this? Before making any attempt to answer we must refer to yet another aspect of the situation. When we say we want to study works of art using the methods of science, we imply that these works have significance quite outside any scientific considerations, and that this significance is the reason for finding them important enough to study. This aspect cannot be ignored. Obviously the practicing conservator can never ignore it, but I suggest that the scientist doing research on works of art cannot ignore it either, even when the research appears to consist entirely of, say, solving problems of analysis and to be quite matter of fact in nature. The distinction to be seen here has been drawn before, perhaps many times.

Anything that we call a work of art is being seen by definition from at least two points of view. One point of view sees it as a physical object, the other looks at whatever properties the object has that lead us to say that it is a work of art, and to attach value to it on this basis. Joseph Margolis (1980) defined a work of art as a token embodied in a physical object. Referring to a work as an image conveys much the same idea. When we speak of such aspects of the work as expressiveness, style, symbolism, the meaning of the whole work or parts of it, any emotional feelings (positive or negative) that may be aroused, we are adopting the token or image point of view. Seeing the work as a physical object is, I believe, self-evident in meaning, and doing so is not confined to the research scientist or conservator; however, to study a work of art using scientific methods means scrutinizing it as a physical object to a greater depth and from more points of view than would be done with any other approach. The specification of what should be studied springs from other parts of human culture.

Traditional art history adopts the token or image point of view largely, though

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

not entirely. Around the late nineteenth to early twentieth century we see examples of art historians, such as Konrad Fiedler, who saw the final form and the style of a work as the product of the interaction of artists with their materials, and Gottfried Semper, who appeared to see art as the byproduct of handicraft (Hauser, 1985). Although this kind of thing does not represent very much that has endured in art historical concepts, the physical object that embodies the art as a token has meant something in traditional art history. For example, art historians have from time to time taken an interest in workshop organization and procedures in the production of paintings (e.g., Phillips, 2000; Shimizu, 1981). For all this, the conceptual framework of art history has been established very largely in aesthetics and similar considerations. It is reasonable to ask how far this can affect our own interest in the same objects of study and how far there can be intersections in the frames of reference.

ART AND TIME

Apart from the fact that we study works of art rather intensively as physical objects, what other commonality can be discerned to make us think that the scientific study of this huge mass of disparate cultural assets can form a coherent subject? One way of looking at it is to say that we study those products of humankind, defined as cultural assets—or art—along each object’s time axis. Such a concept can be divided into three phases. At one end of the time axis we look at the materials the creator (or creators) of an artifact used and how they used them. Then we can consider what changes have occurred in the product. Finally we assess what is the situation for the artifact in question now and how we can predict and influence its life into the future.

We start with the production of the work of art. Art historians talk about the inspiration of the artist, that artist’s vision, the influence of other artists or schools, and so on that results in the creation of the particular thing that we now admire and discuss. The fact remains that no painting or sculpture or anything else springs from somebody’s mind in the fashion of a “thinks” bubble in a cartoon strip. It has to be fashioned from whatever materials were available, using whatever techniques were in use, and these aspects are among the things we are trying to discover about that object. The identity of the artist may or may not be known, and commonly more than one person was involved. We could look on this as investigating the ethnology of the creation of a surviving work. We take account of the historical context and the cultural context in which this process occurred, both of which inevitably had their influences on what was created, which raw materials were used, and on how it all happened. We have a link with human beings who lived in the past—perhaps the recent past, perhaps a more remote past—not just in the sense of the aesthetic concepts or visions they possessed (important as these were) but also in the sense of how they got their hands dirty to make something; ultimately we are investigating not just interesting assemblies of

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

pigments, binders, stone, ceramic, wood, or whatever it may be but the real people who created things.

On to the second phase: What has happened to our cultural asset since it was made. Any artifact, whether artistic or not, starts to change from that moment. The kinetics of such changes vary rather a lot, but on some time scale changes are happening. We call these deterioration mechanisms, and to me as a chemist they are both extremely interesting and quite difficult to study. An understanding of deterioration mechanisms is important from at least two opposite-facing points of view. If we are concerned with the production of an artifact by bygone persons, we are presumably concerned with what they actually produced, which will have changed to a greater or lesser extent in the meantime. There are some areas where such changes are small enough to be ignored but a great many more where they are not. To project our understanding back to the start of the object’s time axis, we need to talk about what has happened to it. This is true even though many artists may have known well that their creations would change over time and they may have been perfectly content with that. The second reason for understanding deterioration mechanisms is conservation, which one may think of as facing forward rather than backward. Conservators are given the responsibility for stabilizing, treating, and perhaps restoring something that has survived in better or worse condition, and trying to ensure its continued survival into the future. To deal with this rationally they need to know what has been happening chemically and physically to the assembly of materials constituting each object.

This links directly to the third phase of our time axis: how to extend it forward as far as possible. The conservator needs to know not only what is there in a material sense but also what is likely to happen with it chemically and physically, possibly after some treatment has been applied. Knowledge of such processes is also needed for any present-day materials that may be used for treatment in the context of the ways in which they are used. Investigations of these complex issues in conservation have become of primary interest in recent years.

IMPLICATIONS FOR THE SCIENTIST

To the researcher in this field who was brought up, as many of us were, in some branch of the mainstream sciences, the demands can be challenging. Typically, work to obtain a scientific research degree, possibly followed by a year or two of postdoctoral research, will lead to proficiency in some branch of science taught in universities, probably a subdiscipline of chemistry or physics. The science thus mastered may be applied to situations arising possibly over many types of works of art and cultural heritage generally. Committed professionals in our field may soon find themselves with some research specialty defined in terms of the works of art themselves; my own, for example, happens to be East Asian paintings. The professional researcher then finds that studying the works of art as physical objects within his chosen area, whether limited or broad, requires the application of

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

scientific knowledge and understanding from a number of scientific disciplines, which may be removed from his original area of proficiency. There has been a kind of orthogonal transposition of concepts; rather than specializing in a single scientific discipline in depth, the researcher needs to take a range of basic disciplines and apply them to a class of objects that will themselves be studied in depth. No doubt this happens in other fields of research too, and it is certainly intellectually stimulating. It can also be alarming. Most scientists, I think, are sensitive to the implications of specialization, to the probability of wandering into error when they venture into branches of science other than their own. The physicist John Ziman published a book (1987) some years ago dealing with questions of mobility and career change in the sciences, including the reasons why most scientists tend to be reluctant to change areas of research in which they work. The problem of how to apply selected, specialized areas of science to a further understanding of things that ultimately have to be understood on their own terms is also an intellectual challenge of the field.

CONCLUSION

I conclude with a few words about the colloquium that followed. For reasons that I mentioned earlier, describing all aspects—or all important aspects—of the scientific examination of art is impractical. We hope to have organized a fair sampling of what the field is about, in all its variety and complexity. This first day was intended to give fairly broad reviews of progress in at least some of the major areas of work. The second day saw accounts of significant progress in more specific topics. This was intended to give us some realistic perspectives on what has been achieved and what has not been achieved in research, particularly that of the past few years. I think that most of the presentations will fit on the time axis of an object that I suggested as describing the kinds of work done. Some may look at questions of the materials and methods used by the creators of artifacts that we choose to call “art,” some at research on deterioration mechanisms, and others at questions of an object’s present status and the prognostications we may have for its future.

In this introductory paper, rather than discussing modern techniques or recent progress, which others will discuss later, I have tried to give some suggestion of depth, even (in a sketchy kind of way) historical depth to the subject. I would like to be able to give it some coherence, but I fear that would be claiming altogether too much. Do we really have just one field here, or several smaller fields that happen to overlap here and there? What are the connections between scientific studies and considerations of aesthetics, the original intent behind creating something, and the connections to questions of intended use? This colloquium was never intended to cast light on problems of this nature, but if we have a serious intellectual discipline underpinning what we do, the more fundamental questions implied by its pursuit should at least be recognized to exist.

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×

REFERENCES

Brommelle, N. 1956. Studies in Conservation 2:176-187.


Caley, E. R. 1951. Journal of Chemical Education 28:64-66.


Hauser, A. 1985. The Philosophy of Art History. Evanston, Ill.: Northwestern University Press. English version of Philosophie der Kunstgeschichte, Oscar Beck, Munich, 1958, pp. 216, 232-234.


Margolis, J. 1980. Art and Philosophy: Conceptual Issues in Aesthetics. Brighton, Sussex: Harvester Press.

Miller, B. F. 1998. In Painting Techniques. History, Materials and Studio Practice. Contributions to the Dublin Congress 7-11 September 1998, eds. A. Roy and P. Smith, pp. 246-248. London: International Institute for Conservation of Historic and Artistic Works.


Nadolny, J. 2003. Reviews in Conservation 4:39-51.


Olin, J. S., ed. 1982. Future Directions in Archaeometry. A Round Table. Washington, D.C.: Smithsonian Institution.


Phillips, Q. E. 2000. The Practices of Painting in Japan, 1475-1500. Stanford, Calif.: Stanford University Press.

Plenderleith, H. J. 1998. Studies in Conservation 43:129-143.


Rees-Jones, S. 1990. Studies in Conservation 35:93-101.


Shimizu, Y. 1981. Archives of Asian Art 34:20-47.


Tennent, N. 1997. In British Museum Occasional Papers, 116: The Interface between Science and Conservation, ed. S. Bradley, pp. 15-23. London: The British Museum.


Watkins, S. C. 1997. In British Museum Occasional Papers, 116: The Interface between Science and Conservation, ed. S. Bradley, pp. 221-226. London: The British Museum.


Ziman, J. 1987. Knowing Everything about Nothing. Specialization and Change in Scientific Careers. Cambridge: Cambridge University Press.

Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
Page 7
Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
Page 9
Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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Suggested Citation:"The State of the Field - Overview--John Winter." National Academy of Sciences. 2005. Scientific Examination of Art: Modern Techniques in Conservation and Analysis. Washington, DC: The National Academies Press. doi: 10.17226/11413.
×
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In March 2003, the National Academy of Sciences Arthur M. Sackler Colloquia presented the Scientific Examination of Art: Modern Techniques in Conservation and Analysis at the National Academy of Sciences Building in Washington, DC. Featuring senior investigators of specific methods and materials, the papers in this book examine the application of scientific methods to the study and conservation of art and cultural properties.

The Arthur M. Sackler Colloquia of the National Academy of Sciences address scientific topics of broad and current interest, cutting across the boundaries of traditional disciplines and attracting up to 250 leading researchers in the field. These colloquia are made possible by a generous gift from Mrs. Jill Sackler, in memory of her husband, Arthur M. Sackler.

For more information about the Sackler Colloquia, visit www.nasonline.org/sackler

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