Things Fall Apart

Some things decay slowly, such as radioactive isotopes, while others are designed to be disposable, like a paper cup. We’re surrounded by constant change as we reclaim, reuse, and reimagine our material environment.

Microscopes have been used to examine artworks for over a century—but these tools have become more and more complex. This Transmission Electron Microscope (TEM), a Hitachi Perkin-Elmer Model HS-9, sends a beam of accelerated electrons through a specimen. Electromagnets aim the beam to interact with the electrons of the sample. Instruments like these improve our ability to identify even the most unusual materials.

Compound optical microscopes use a series of lenses to focus light on a sample, magnifying it to several hundred times its size. Early art conservators used these to help identify materials and assess any damage or loss over time.

In our gallery the painting is displayed on its back so that it won’t lose more of its fragile surface.

What did the bookworm say to the library? It's been nice gnawing you! Okay, there’s nothing funny about destructive insects.

Museums and libraries work hard to prevent pests. That’s one reason why there’s no food and drink allowed.

What we call “bookworms” can be one of many types of moths, beetles, or lice. They bore through leather and cloth bindings, or feed on the microscopic molds and fungi that grow inside damp books.

You can see a latticework of holes in this encyclopedia volume. In early modern China, some books were treated with arsenic to repel insects. Today, infested collections may be treated with fumigation, but many modern conservators prefer to treat books using extreme temperatures—like freezing—rather than chemicals.

From Bakelite to Tupperware, advertisements hailed the promises of plastics: lightweight, unbreakable, and affordable. But no material—even flexible, durable plastic—escapes decay. Plastics are the wonder material of the 20th century. But their rapid—and unpredictable—decay has left conservators searching for solutions.

One major roadblock to preserving plastics is first identifying them. This Plastic Test Sample is a perfect example. Its composition is unknown, because it was created in as a test by chemist Daniel W. Fox, inventor of LEXAN (a type of polycarbonate resin). So what is it made of? That’s for a spectrophotometer to know and you to find out.

Lexan is a resin thermoplastic developed by chemist Daniel Fox in 1953. It’s similar to Plexiglass in appearance yet durable enough to be used in bulletproof “glass.” Nalgene water bottles, iPod casings, and aerospace windows are all made from Lexan.

Some decay is irreversible. Some is inspirational. Artisans such as Louis Comfort Tiffany loved the unusual look of archaeological glass. Our Roman ball flask, dating to about 200 CE, shows off a multicolored, opalescent shine that took a millennium to achieve. It results from being buried in moist soil for centuries, as chemicals leached to the surface.

How can we tell when UV rays (like sunlight) have damaged a colorful work of art? Colorimetry is the scientific approach to describing, quantifying, and comparing color. It’s also important in making comparisons before and after conservation, and studying the effectiveness of UV-resistant coatings.

Though this Putnam Dyes Sign remains bright, time and rust have caught up to it. The history of dye-making is a long struggle to create colors that will resist the effects of light, especially the UV spectrum. UV rays break down the bonds in chromophores—the parts of a molecule that absorb light and produce color. The result is bleaching or fading.

This Bausch & Lomb colorimeter was based on an earlier design by Louis Jules Duboscq, a French instrument maker. To examine an object with a colorimeter, you’d first take a physical sample such as a chip of paint or a small piece of thread.

Contemporary conservation is a field where common-sense precautions meet high-tech analysis.

When the National Gallery in London began to clean paintings in 1846, people were shocked by the newly bright surfaces. Critics called the pictures “scraped raw.” But by the 1960s, conservation laboratories were being built at museums around the world, and today the science of conservation continues to evolve and adapt.

Unlike a protective patina, rust actively destroys. The iron oxides that form eventually flake away, leaving exposed metal and holes.

Many people who owned chemistry sets played with them in a basement or garage—damp places that can speed up the process of disintegration. High levels of sulfur dioxide, carbon dioxide, or salt can also cause metal to rust more quickly.

The pattern of surface decay can tell us how an object was used or stored. Take this brass mortar, which is speckled with green copper oxide—almost like a leopard’s spots—on the inside of the wide rim. The outside has stayed a shiny golden color. This unusual patterning might be a result of exposure to compounds mixed inside the mortar, leaving the outside untouched.

Decay shows us complex natural forces at work—from cracks caused by humidity, to color faded by UV light, to rust and stains, but repair and preservation teach us about the values and struggles of those who came before us. We hope you’ve enjoyed learning more about how and why “Things Fall Apart” and what we do to preserve them!