Conservation treatments progress slowly because there is a lot of research involved, and the Bacchus Conservation Project is no exception. We want to know things about the sculpture that will not only inform the conservation treatment but also tell us more about how the statue was put together and if (and when) it was subsequently repaired. After the 3-D structured light scan in January, Bacchus was due for a full scientific checkup.
With the 3-D digital images of Bacchus in hand, we talked to structural engineers Chuck Lysaght and Andrew Terrell at Lysaght & Associates to find out more about the structural integrity of the statue. It’s a bit unusual for engineers to work on a project like this, but they were excited to meet a new challenge! Bacchus seems stable, but we want to investigate the breaks in the right leg and find out what would happen when weight is removed from or added to the sculpture. The preliminary study determined that the engineers would be able to answer our questions, so the actual study is now under way.
An important phase of the project is sampling, which is done to help answer two major research questions. Sampling is a destructive process, but it was the only way to get certain information we need to understand the sculpture. So, we had to scrape, drill, swab, or chip tiny pieces of Bacchus to send for testing. (Scary!) Marble sampling had been done in the ’80s, but we could not find all the sampling locations. This is problematic because Bacchus is made from various fragments, and we need to know exactly where the samples were taken in order to interpret the data correctly. So, we took new samples for stable isotope analysis, which is rather unnerving because NCMA Objects Conservator Corey Riley had to drill holes into Bacchus! (Yes, with a drill!) The goal of isotopic analysis is to find out from which quarries the marble most likely originated. Little vials of white marble powder were sent to Scott Pike at Willamette University for analysis.
Riley also prepped Bacchus for another sampling session, this time of the materials used to join the various fragments or repair subsequent breaks, as well as of surface patinas and grime. Patches and plugs were removed to reveal some of the metal rods inside the statue. Jennifer Mass and Adam Finnefrock of Scientific Analysis of Fine Art, LLC “operated” on Bacchus for a day and a half to take various types of samples. The analysis of these samples will help us put together the history of the sculpture, from its creation using fragments until now. Oddly enough, this information can also help the engineers with the structural analysis.
And now we await the results.