William Howard Taft’s family has strong historical connections to both the city of Cincinnati, and the University. Taft served Cincinnati both as a federal circuit judge and as Dean of the Cincinnati College (the forerunner of The University of Cincinnati). In honor of Taft’s contributions merging the UC law department with Cincinnati College in 1896, a statue was erected in front of the Law building in 1992.
And now, for Halloween, William has made it across campus to the Preservation Lab. And this surprise has taken a gruesome turn. A maquette of Will’s head from the Archives and Rare Books Library collection is aging poorly and in need of treatment and preservation storage. In preparation for bronze casting, Will’s head was sculpted by an artist out of a moldable putty and mounted to a metal rod. It is where the two materials meet that the preservation horrors arise!
A reddish-orange, oily slime is oozing from the interior of the putty down to where the rod stand is secured into a wooden base.
Preliminary research indicates the head is sculpted from a material commonly referred to as plastiline, Apoxie or Milliput. Recipes of putties such as these are vast, but generally contain a filler, a wax, and an oily component such as castor oil or petroleum jelly. Fillers might include clay, starch, talcum or even sulfur depending on the proprietary or homemade concoction. By the 1990’s the negative effects of using sulfur would have been known, so it’s possible that the putty is sulfur-free; however, the possibility should not be discounted. According to plastiline research by Gerhard Eggert, located on the Museum of Fine Arts CAMEO website, putties containing sulfur were preferred by artists for their superior sculpting properties. Another likely alternative is that the putty is suffering from its own inherent vice. In other words, the weeping could be due to the putty’s unstable chemical composition that is leading to its own demise… not to mention off-gassing that might be corroding the metal below!
While the specific type of metal that the head is mounted on is currently a mystery, we do know it is ferrous. Using a magnet, I discovered the metal rod contains a magnetic pull, indicating it is at least partially comprised of iron.
Despite this research, there is one pressing questions left to answer:
Is the weeping due to an inherent vice of the putty alone… or is oozing liquid created by a unique chemical reaction resulting from contact between the putty and the metal rod?
The answer to this question will help us to determine whether a barrier between the two materials might help prevent weeping in the future.
In order create a more informed treatment proposal, more research and analytical testing will need to be conducted in order to better understand what is leading to this mysterious preservation horror. Since this project ranges out of scope for the Preservation Lab, the expertise of an Objects Conservator will be sought!
Ashleigh Schieszer (PLCH) – Book & Paper Conservator
Resources and Further Research: