The types of papers range widely because artists use tracing paper, mechanical paper, crepe paper, and electrical paper, in addition to fine art papers. Someone like Rauschenberg is going to use what he's going to use. Sample books are full of printed details—such as the paper names, dimensions, and weights—and are readily available. It's hard to get your hands on full sheets of paper, although they tell a whole different story. Typically, deckles are trimmed off in a sample book, but in a full sheet, whether handmade or mould-made on a cylinder machine, you can see full deckles and watermarks. hp: What are some of the ways the paper sample collection is useful? mpd: Well, to begin with, sample books were kept closed and the individual sheets usually stored in the dark. When we're lucky, they're in good condition, so they may, for example, show the color of a cream paper pretty much as it was when it was made, as opposed to what it would look like if—as so often happens—it had been put on a wall and left there for a long time. Vastly different. Similarly, early colored papers—such as the Fabriano Ingres papers used by Picasso in his 1913 collage The Cup of Coffee—often were not lightfast. The paper used for the guitar face was originally pinky-mauve. The color has since faded to gray, except in the lower right corner which was hidden under the coffee cup. We look at the gray guitar at the center of Picasso's collage and think: "Boy is that boring." Well it wasn't boring when it was new. Using an unfaded piece of the same paper from a 1905 Fabriano sample book as a reference—verified by its matching watermark—we can digitally reconstruct the true color for an art historian and say: "This is what it really looked like." hp: The recent closing of New York Central Art Supply and its renowned paper section was a grave blow to many artists and paper lovers. That business and its principals have long been generous to the NGA paper collection. Can you share with us your recent interactions with them? mpd: Over the past several years, we have attempted to purchase full sheets of most of the Western papers in the New York Central catalogue, as well as many Asian papers. After the announcement that the store would close, Michael Skalka \[who heads the related Artists' Materials Collection at the National Gallery of Art\] and I visited New York Central in August 2016. From the fourth-floor attic, we collected: retired papers; several generations of labeled counter books; vertical display panels; and older 3 x 5-inch rectangles of paper that had been used to make up swatch books, labeled by maker, size, weight, and color. The company donated the bulk of their enormous 6 x 8-foot swatch collection of contemporary papers to the three conservation graduate schools (the Art Conservation Department at SUNY Buffalo State, the Winterthur/University of Delaware Program in Art Conservation, and the Conservation Center of the Institute of Fine Arts at New York University) for research. hp: What is the chronological scope of the PSC and what does it reveal about the quality of artists' papers during this period? mpd: The PSC ranges from late nineteenth- and early-twentiethcentury papers up to the present. Unfortunately, clearly identified and dated papers don't exist much until the mid-nineteenth century. Richard Herring's A Practical Guide to the Varieties and Relative Values of Paper, published in London in 1860, is our first dated paper sample book. Overall during this period, I can see a decline, a growing drought in the finest artist papers. Traditional hand papermaking was traumatized in the late nineteenth century after the arrival of the papermaking machine \[first patented in 1799\]. Book printers and even artists preferred cheaper, smooth, machine-made wove paper to the artisanal product, and the number of hand paper mills declined. Then, around the turn of the twentieth century, the hand-crafted book revival in England and the United States helped to increase demand for traditional handmade paper. Fine and decorative papers for luxury printing began to be imported into the United States after 1901 by the Japan Paper Company. Fine imported artist papers also appeared in the catalogs of artists' materials supply companies like Weber in Philadelphia. Throughout the 1920s all kinds of paper could be obtained in America, but by the 1930s, nobody had any money and the sale of fine papers tapered off. World War II came and paper production was diverted to wartime needs. Then in the early 1950s, many remaining great hand mills in England collapsed. Paper flooded into the US as the old stocks of these mills were sold off. Amazingly, some of these stocks remained available all the way into the 1990s in New York. So artists there were able to find wonderful old papers for a long time. But, Fourdrinier-machine-made paper and cylinder-mouldmade paper really dominated the fine art market after World War II. Variety was limited in the 1950s. In the 1960s, however, artists and printmakers began to demand a greater selection of paper. Andrews/ Nelson/Whitehead (A/N/W, successor to the Japan Paper Company) strove to import better papers. New York Central Art Supply worked hard to stock more and better papers. hp: Yes, there's a reference in Judith Walsh's 2001 article \[Summer 2001, Volume 16, Number 1\] about Vera Freeman of A/N/W making a concerted effort, at June Wayne's request, to import better papers. mpd: In fact, paper technology was still not as good as it could have been. Cotton emerged as the major fiber and linen became rare. Rives de Lin remained a linen paper, but fewer mills could handle linen. And sizing was in the acidic range. The machines were running with starch or maybe alum sizing; they were not alkaline. You can see it in the sample books of the 1960s from the major European mills. The papers don't age very well. They don't fox, necessarily, but they yellow and just look dingy—even papers that have never seen the light of day. Around the 1970s, the paper permanence movement emerged. The desire for longer-lasting papers came from artists, from conservators and museums, and especially from the library community. The major US standard, Permanence of Paper for Printed Library Materials, ANSI Z39.48, appeared in 1984. The permanence transformation appeared in Europe right at the end of the 1970s, when the French paper conglomerate Arjomari transferred production of Rives fine art papers to its sister mill, Arches. The papers were reformulated to use neutral sizing and calcium carbonate for longer life. Arches changed the watermarks and incorporated an infinity symbol and a little date code. This all happened in the period from 1979 to 1982. hp: To what extent does the NGA collection represent handmade papers made over the past forty years, roughly the period of resurgent interest in the field? mpd: I pay attention to a few hand papermaking concerns, like Twinrocker and Cave Paper, but I think our collecting is a little more historical now. Twinrocker's still going although the Clarks have retired; Saint-Armand in Canada has a hand operation and we pay attention to that. I haven't followed Tim Barrett at the University of Iowa as much, because I think of his group as focusing more on research than on significant paper production. Perhaps I'm wrong. Recently the conservators at the Library of Congress gave me a list of hand paper mills that they're buying from. So, I will take a look. Papermakers always need to figure out who they can sell to. My perception is that the letterpress market has picked up. It's a market that can be tapped. The digital market has become enormous, so we started collecting papers used for digital printmaking. Originally, digital ink was not stable on some papers. So the papermaking industry, including all of the big companies, like Canson, Arches, and Hahnemuhle, established relationships with external coating companies to develop coatings for their papers. Even Hiromi Paper, Inc. is selling Japanese papers enhanced for digital printmaking because there's such a huge market. hp: The NGA paper collection is associated with the museum's Conservation Department. What are some ways in which the department's staff has used the collection in its work and in support of art historians at the NGA? mpd: Amy Hughes used the PSC to identify the decorative paper used in a Max Weber woodcut that needed treatment. Discolored adhesive on the back had stained through to the front of the paper. She found the same type of Japanese paper, known as momigami, in the sample collection and by testing a small area determined how best to treat the print. \[See following article by Amy Hughes for more on Weber woodcut.—Ed.\] hp: Has the PSC ever been used in a legal case to prove or disprove a point of fact? mpd: It was involved indirectly. The PSC was formed by Judith Walsh in the early 1990s. Judith researched the papers used by Georgia O'Keeffe for the Georgia O'Keeffe Catalogue Raisonne by Barbara Buhler Lynes. The volumes included Judy's characterizations of the artist's drawing papers. Knowledge of the types of paper O'Keeffe liked to use, the kinds of paper she never used, and those she could never have used (because they weren't available) became important during a dispute over the authenticity of the Canyon Suite watercolors at the Kemper Museum. hp: To what extent do independent researchers have access to the NGA's paper collection? mpd: Individual researchers have full guided access to the actual materials through the Paper Conservation Department. The records are stored in the Gallery Archives. The collection has a web presence on the National Gallery website under Conservation/Resources/Paper Sample Collection. \[www.nga.gov/content/ngaweb/conservation/paper-sample.html\] hp: What kinds of work are you doing now to expand the PSC? mpd: My colleagues and I regularly visit mills and acquire sample books. We also take photographs and videos of the mills. And we're doing interviews with people who work in papermaking, which we're depositing in the Gallery Archives. We plan to do that soon for the Saint-Armand Paper Mill. We recently interviewed the directors of Legion Paper Corporation. And we want to send someone out to Los Angeles to interview Hiromi Katayama. hp: How about Japanese Paper Place in Toronto? mpd: Yes, I've talked to Nancy Jacobi about this. She would make a great interviewee. Let me stress that we collect paper, but we also try to collect histories, photographs, and supporting documentation— such as price lists and advertising—all of which are incredibly important. hp: What do you see as the future of the NGA's paper collection? mpd: We would like to put the database and transmitted light photographs of the watermarks online. The amount of information actually printed in the sample books can be extensive, so we would like to scan pages that list whether the paper is handmade or cylindermould- made, the fibers and sizing used, information about the watermarks, deckles, colors, dimensions, and prices. This material would be invaluable for researchers.