Cross-Campus Conservation Collaboration!

by Adrienne Gendron

Professional conservators generally specialize by material type. All the conservators at the Penn Museum specialize in objects, which includes a wide variety of materials from stone and ceramics to leather and wood. However, occasionally materials come across our desks that fall outside our areas of expertise. The Penn Museum recently acquired twelve Indian paintings on paper which need to be hinged so they can be safely handled by researchers. Because paper is a separate sub-specialty of conservation, we called on our friends at the Steven Miller Conservation Lab at the Penn Libraries’ Kislak Center for Special Collections, Rare Books and Manuscripts to help us with this task. This is not the first time we have taken advantage of our book and paper conservation colleagues right here on campus – follow this link to read about a recent treatment carried out in their labs on a parchment scroll.

In the case of the hinging project, our Penn Libraries conservation colleagues came to us – a couple weeks ago, Elizabeth McDermott, Tessa Gadomski, and Sarah Reidell visited our lab to provide a workshop on how to properly hinge paper objects for display.

Penn Museum conservators and interns listening to Liz and Tessa give instruction.

Hinging is a process in which small strips of paper are carefully adhered to the back of a work of art on paper in order to secure it within a window mat. It results in a strong and secure housing solution that ensures the safety of the object for storage and display.

One of the twelve works on paper that needs to be hinged (2017-22-13).

The most common and secure method of hinging is called a T hinge, which is composed of two strips of Japanese tissue paper. First, a strip of paper is carefully cut to size and a small amount of reversible adhesive is applied. Then, the strip is applied to the back of the top edge of the work and allowed to dry under weights.

The first strips in place along the top edge of a sample object.

Next, the work is flipped face-up and positioned on its backing mat. This is the trickiest part of the process, as the work must be perfectly positioned so that when the window mat is closed, it appears centered. Then, a second strip is adhered over the first strip and onto the backing board to secure the work in place.

The second strips applied over the first strips and onto the backing board, securing the work in place.

Because conservation is a small field, people often call on colleagues to for advice when it comes to different areas of expertise. We’re excited to apply our new skill to the twelve Indian paintings to ensure their long-term safety and preservation. Hinging can be a tricky business, but after our workshop we’re up for the challenge!

The first Indian work on paper we successfully hinged using techniques from the workshop (2017-22-20). When executed properly, hinges can allow a work to be flipped up so the back can be viewed.

Treatment of a parchment scroll from Ethiopia: an objects conservator changes dimensions

by Teresa Jimenez-Millas

During the past month I have had the great opportunity of working on a parchment treatment under the supervision of Sarah Reidell, the Margy E. Meyerson Head of Conservation, Tessa Gadomski, Conservation Librarian, and the rest of the fantastic team in the Steven Miller Conservation Lab at the Penn Libraries’ Kislak Center for Special Collections, Rare Books and Manuscripts.

The parchment is an Ethiopian prayer scroll (29-94-123) in our Museum’s collection that we are treating for the opening of the Africa Galleries this November 2019.

In The Walters Art Museum online catalogue, there are similar scrolls to this one. The Walters describes them as, “Ethiopian prayer scrolls were made to be the length of the person who commissioned them, thereby protecting the owner from head to toe.”

This scroll is made of three sections of parchment sewn together using parchment strips/thongs (0.5 cm) from the same kind of animal. Parchment is a sheet material that is made from the skin of domesticated animals such as calves, sheep, and goats, cleaned of their hair and flesh and then dried under tension on a frame. It is a mechanical process and the skin is not chemically tanned. Further analytical methods such as scanning electron microscopy (SEM) or Peptide Mass Fingerprinting (PMF) would give us more information as to the kind of protein and other features that would help us to identify the type of skin.

The first step on this new and exciting project was a close examination of the object under a stereo binocular microscopic (Leica IC80HD). In my examinations, I noticed some interesting features that I would not have been able to understand without Sarah’s expertise, and I’d like to share some of these cool details here.

At first glance, the third section of the scroll has a 9 cm stitched repair that one might think was made after the parchment was manufactured. But as I learned, the process of manufacturing parchment involves drying the material under tension, which leads to marked changes in fiber orientation, and inevitably involves some degree of breakage of certain fibers in the dermal network.

The stitched repair is circled in red

Observation under magnification with Microscope LEICA IC80D we can see that the sewing holes are very round but are not punched. The holes appear to have been pierced when the skin was wet, and the parchment dried around the stitching creating ridged folds that are now keeping the split closed.

The thread is still present in about 25% of the repair. The edges of the thread are not cut but are frayed. At some areas we can still see some remains of black ink that also indicate that the scribe probably wrote over the repair. All these observations indicate that this repair was made during the manufacturing process of the parchment, while still wet.

I will write more about the treatment of this object in a future post!