I went into this final unit of class with equal doses of excitement and trepidation. Excitement over learning this new aspect of manuscript study alongside my students; trepidation over not knowing how best to help them prepare. Some of my assignment scaffolding decisions turned out to be spot on, and my students kindly helped me think through ways to improve other assignments for future classes.
So in this pedagogy post, I’ll walk you through the unit: what I did when, and what I could have done (and will do next time). If you’re reading this blog for its “pretty manuscripts and cool science” posts, you may want to give this one a pass. But if you’re a fellow professor whose thinking about integrating a unit on how pigments were sourced, made, and even analyzed today, you may find my experience (and my students’ suggestions) enlightening.
The unit began with us returning to the basics of manuscript study: how a manuscript was made, with emphasis on the ruling, writing, and decoration. We spent most of our time on inks and pigments; in retrospect, I realize we should have recapped the process of making parchment as well, because those preparation methods leave elemental residues on the parchment. As I’ve blogged about before, each student was assigned a color and produced a detailed, exhaustive report on the different ways that color might be produced in the later Middle Ages. Those reports were then shared with the class as a way of croudsourcing foundational information for the rest of the unit. As an assignment, it worked excellently (and led some students to write fascinating blog posts on pinks, browns, more browns, and verdigris). The students were well prepared to think about the different ways that colors were made, and each student then became an expert on blues, or reds, or white for the group. This division of labor could work in our course because we had a limited enrollment; with a larger class, students could be assigned different organic and inorganic pigments (instead of colors).
I’d like to expand one side assignment that came out of these color reports: the sourcing and mapping of pigments. In their color reports, the students noted where the raw materials for their pigments came from, so we spent one class day discussing the manufacture and trading of pigments. I gave them a Google Map and asked them to pin the location(s) where their pigments’ raw materials might have come from, with fifteenth-century Paris as our center of manuscript production. I did verdigris as a sample. Verdigris is made by suspending copper over an acid (like vinegar or wine), then scraping off the green patina that forms. I therefore put pins in places near Paris where these raw materials were produced; I also pinned Montpellier as a major verdigris producer. From that (admittedly impressionistic) model, the students pinned similarly rough information for their different pigments. The end result was this Google Map (built on a map originally constructed, I believe, by Alan Farber of the University of Oneonta). It’s a loosey-goosey picture of where pigments came from, and I won’t vouch for the accuracy of all its pins. Nevertheless, it’s a start at visualizing the international trade and regional mining/manufacturing that lay behind these colors.
This assignment wants to become more robust (maybe even turned into a GIS mapping DH project by someone else!) to visualize more accurately the movements of rare and mundane materials. Through primary and secondary source research, students should be able to identify locations where pigments were manufactured, the ports through which they were imported, their wholesale and retail prices, and more. Such a map — or maps, if the trade information could be refined by decade – could insightfully plot the changes in trade, price, and pigment use over time. When vermillion came to be manufactured, did imports of cinnebar dry up? Did London limners import their verdigris from the Montpellier manufacturers, or did they produce it locally? How did the rise of the Ottoman empire affect the trade of lapis lazuli (and other commodities) from the Middle East? My students found questions like these intriguing, because they reintroduce the human element into the production of manuscripts: the scribes whose efforts we see and the pigment makers (sometimes women!) necessary for the illuminators.
Amidst this section of the unit fell our “playing with pigments” day, run by my two Honors students who experimented with medieval-ish ways of making paint and then showed us how it was done. It was especially helpful to see the different shades of green that verdigris could produce, or the way that different binders produced slightly different opacities of paint. And everyone can use a break from the usual classroom routine!
My students had a solid grounding in the way medieval paints were made, I believe, and that preparation served them well throughout the chemical analysis part of the unit. I additionally had them write fragment hypotheses: each pair developed research questions about their fragments’ colors and hypothesized which pigments, and therefore which elements, might be present in their fragments. When it came time to test those hypotheses with the pXRF device and Dr. Alice Hunt’s assistance, however, we discovered the gaps in my course planning.
In particular, the students needed more help grappling with the unit’s hard science. We needed a “Periodic Table 101” day so the students could better understand why we might see some elements (like zinc) but not others (like gallium). We needed more aids for understanding the way the pXRF device works. The reading Dr. Hunt provided was not geared for humanities majors, and while her lecture clearly explained the device’s functionality, we needed that kind of “translated” information to help students make it through the pXRF documentation. Fortunately, we now have a great student blog post that starts that translation process, and next time I will also devise a reading guide for the pXRF manual.
During (and after) the sampling process, I discovered more blind spots in our prep. When choosing our sampling spots, we needed to ensure there was nothing on the backside of the parchment that would mask our results, since the x-rays penetrate the whole parchment. During the sampling, we also needed to record the pXRF’s settings, so we could include that data in our final reports. Finally, in addition to sampling the pigments, we needed to take “control” samples of plain parchment and unadorned ink. The process of preparing the parchment (soaking the animal skins in lime, scraping the parchment with metal tools, ruling the parchment with plummet) left elemental residues that the pXRF could identify – which is cool to find, but those readings would then need to be subtracted from the pigment readings. Sometimes those background levels of elements were not intrusive in interpreting the spectra, but they could be. Knowing the background levels of calcium in the parchment, for instance, proved to be necessary in helping this pair of students identify a calcium-based white as part of their pink pigment.
Finally, the students wanted an introduction to reading scientific publications. Although the print and digital resources the librarians curated were sufficient for understanding how pigments were typically produced, the students needed to delve into the scientific literature to try to solve our atypical puzzles. For instance, what does chemical analysis reveals about trace elements in iron gall inks? What gold alloys were common, and in what ratios? Some of our outstanding questions are answerable, and the students tried gamely to navigate the literature to find answers. Still, they needed more practice with this form of scholarship to be able to cull useful answers from the literature – and that need is reflected in the sometimes-scattershot use of resources in their blog post bibliographies.
Despite the ways in which I hadn’t prepared them sufficiently, my students made amazing discoveries about their fragments and pigments. Their curiosity, dedication, and in (a few cases) sheer cussedness were motivating. This project pushed all of them to try out new investigative and analytic methods, and I think they all found in themselves an interest in some aspect of this science stuff that they hadn’t anticipated. Certainly I’m incredibly proud of their efforts, their willingness to work with me and Dr. Hunt, and their ambition throughout the course.
ps I’m always happy to share specific prompts/assignments with interested instructors. Contact info available on the About page!