ISAS Researchers Study Perishable Materials
Mary Simon (ISAS senior archaeobotanist), Mary King (ISAS assistant archaeobotanist), and Carol Richards (ISU graduate student) participated in a 4-day fabric analysis training workshop at the R. L. Andrews Center for Perishables Analysis at Mercyhurst College in Erie, Pennsylvania. Their goal was to better understand and interpret fiber perishable remains recovered from archaeological sites in Illinois. These include both pieces of carbonized fabrics or cordage as well as the impressions of cords or fabrics on pottery sherds.
Between October 30–November 4, Simon, King, and Richards met with workshop leader and fiber perishable expert, Jeff Illingworth. Mercyhurst’s Dr. James Adovasio, who is a nationally recognized leading expert in the field, and Dr. Edward Jolie, who recently completed a detailed study of fiber perishables from the Chaco Canyon area, also participated in the workshop.
Recent, and very rare, finds of carbonized matting, cordage, and fabric from ISAS excavations in and around East St Louis, Illinois provided the impetus for the workshop. These unusual items represent only a tiny portion of perishable culture, most of which is lost to the archaeological record. In fact, notes Illingworth, 85 percent or more of all prehistoric cultural items were constructed of perishable materials. For the most part, these items leave little to no trace in the archaeological record.
The researchers spent the bulk of the workshop with Illingworth learning the basics of cordage and fabric production using plant fibers. Because fabric production is an additive process, each step—from selecting and collecting raw plant materials through product completion and disposal when use life is complete—is represented in the piece. Understanding the technological processes of production and describing them using the correct terminology, is the first step in the analytical process. Such analysis can inform on questions such as raw material selection, processing, spinning technology, construction form and perhaps function, and even secondary use-life. Some of the questions Simon, King, and Richards consider include: What happens to the product after use life? How were people making fabrics? How do these steps differ as the object’s required output differs? “At the most basic level, these analyses help us to get at technological questions of production,” says Simon.
Researchers also spent time with Drs. Adovasio and Jolie, as well as Illingworth, discussing the implications of this research. Because they are a direct reflection of people’s decisions, changes in any step of the processes can reflect not only differences in desired outputs but also other aspects of cultural change. For example, differences through time may involve contact with new groups, whether through actual population movement or idea exchange; changing technological needs or innovations in technology; or even changes in ritual or belief as reflected in fabric construction. Further, because fabric construction is cultural, differences in contemporary collections may in be indicative of ethnic boundaries.
Though actual materials are rare, indirect evidence of perishable fabrics or cordage is common on pottery from Illinois. Simon, King, Richards, and Illingworth made clay impressions of cord and fabric marked pottery from a recently excavated archaeological site in southwestern Illinois dating to between about A.D. 800 and 1,000. These positive casts can be interpreted in the same manner as the original textiles. Although sherd surfaces were superficially similar, the impressions showed that at least four different types of textiles and modes of application were used for decorating. These studies speak to the richness of the material culture not otherwise evident.
Ceramic impressions of perishable materials are an important area of study for understanding prehistoric culture in Illinois. However, training is necessary. “This workshop will help us better understand and study these remains,” says Simon. One question of immediate interest is the shift from using cordage spun in one direction to cordage spun in the opposite direction, a phenomenon that has been widely recorded for late first millennium A.D. sites in western Illinois. Richards is addressing this in her forthcoming Master’s thesis.
During the workshop, Simon, King, and Richards studied Mercyhurst prehistoric fabric collections and discussed ways to conserve and curate the delicate materials. This information will be used to enable ISAS staff to maintain the integrity of fragile, carbonized fiber perishables for future research.
The collaboration between Mercyhurst and ISAS began several years ago when ISAS excavated a plaited fabric piece at the East St. Louis site [link]. Upon the recommendation of Dr. Penelope Drooker, Simon contacted Illingworth at Mercyhurst for assistance with the fabric analysis. Illingworth visited the Paleoethnobotanical Laboratory in Champaign, preformed descriptive analysis, and prepared a short report. “This workshop was an outgrowth of those efforts, but was a long time coming. Mercyhurst is one of the few places in the US with specialists in this area,” says Simon.
“It was a very informative course, and we'll be digesting the information for some time to come,” says King of her experience.
[posted November 15, 2011]