Boston College is a liberal arts university. Each undergraduate student is required to take classes in history, science, mathematics, foreign language, theology, social science, philosophy, English and cultural diversity, unless he or she was lucky enough to “AP out” with credits from those long-ago high school days. Though BC’s core has good intentions, students often see the core as something to “get through” and often connections between classes are severely lacking. I am not sure what connections you could make between Molecules and Cells and Europe and the Modern World I, other than perhaps the stretched connection that the people involved in history are, in fact, made up of cells. Personally, I’ve always admired the spirit of the core and what it aims to achieve. Yet I had never felt a total integration of disciplines until I carried a miniscule sample taken from a sacristy crucifix to a lab on the first floor of Higgins. This crucifix, now held in the University Archives, is from the Immaculate Conception Church, the Jesuit church which was part of our original campus in Boston’s South End.
As a conservation assistant at the Burns Library, I assist Barbara Adams Hebard with preservation of old books and other materials, including religious artifacts like this crucifix. She needed to re-attach Jesus’s leg, and I must say; the one-legged crucifix was quite a gruesome sight. Wanting her repair to stick—literally—she needed to know the exact composition of the piece in order to use the correct adhesive. She concluded that a structure from the 19th century would most likely consist of lime or gypsum. I received the honor of taking a small sample of Jesus’s leg (mere particles of dust) to Dr. McMahon, BC’s multi-beam SEM/FIB research specialist, to have it analyzed under the electron microscope in order to determine just which compound made up the crucifix. Ushered into a small room packed with machines, I was shown to a chair beside a monstrously humongous device and a monstrously old computer. I observed as Dr. McMahon placed a small particle of dust from Jesus’s leg on a platform, inserted it into the machine, and waited for the vacuum to accommodate. Then he moved the sample into the body of the machine. At first, he had to make quite a few adjustments on the machine, twirling knobs this way and that, but eventually a usable spectrum was obtained. It contained sulfur as well as carbon. McMahon decided to run a few more samples to clarify. The next one contained tons of carbon and no sulfur. I was beginning to grow confused. How would we know which adhesive to use when such a specific machine was giving conflicting results?
Mainly C would mean lime but any S would mean gypsum. Now, of course, a crucifix this old may well have been previously repaired, which could lead to contamination of the fixture. We concluded that the samples containing mostly carbon and calcium were pieces of the old lime glue used in previous repairs. The actual structure was made of sulfur, oxygen and calcium. Having two years of college chemistry under my belt, I looked at one of the clearest spectrums, and using the relative areas under each peak, figured out that the crucifix consisted of 1 S: 1 Ca: 4 O’s. I asked Dr. McMahon if the compound was CaSO4 which he confirmed, politely pretending to be impressed by my basic chemistry skills. Though Dr. McMahon could have easily done this spectroscopy in his sleep, I was extremely excited by what this scientific technology could do and how it integrated seamlessly into my work at the Burns’ conservation lab.
Adams Hebard enlisted Michaela Neiro, Objects Conservator at Historic New England, with whom she had served as a Board Member of the New England Conservation Association, to advise her on the selection of an adhesive. Neiro recommended Acryloid B-72 (ethyl methacrylate copolymer) in acetone. Having taken organic chemistry, I even know what a copolymer is! While working as a book conservator at the Boston Athenaeum, Adams Hebard had taken a week-long workshop entitled “Chemistry for Conservators” at Johns Hopkins University, which was taught by British conservator David Dorning. This workshop was designed to help conservators deal with challenges such as these. However, she probably never thought she’d collaborate with a scientist equipped with an electron microscope for her conservation work – just as Dr. McMahon probably never dreamed he’d analyze a piece of Jesus’s leg from a crucifix when he specialized in microscopy. This is a clear collision of disciplines, and one close to my heart, being a premedical student who works in a library conservation lab. Boston College’s core curriculum may need some reworking, but I have hope that this process can be successful. BC has resources available in virtually every discipline. As students, all we need is to be alerted to these cross-disciplinary opportunities in order to take full advantage of them.
- Anna Whitham, Conservation Assistant, John J. Burns Library.