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Fossils in Architecture

Categories: Articles

A coiled nautiloid fossil, approximately 480 million years old, in the floor of Gallery 1 of the West Building, National Gallery of Art. Photo by Judith Barr.

Christopher Barr is a lawyer who has lived in Washington, D.C. since 1979 and knows the city in an unusual way: through discovering public fossils in the city’s architecture. Though he majored in history in his undergrad, he took several geology courses that solidified a continued interest in paleontology. He now documents his findings on his blog fossils in the architecture of washington, d.c.: a guide to washington’s accidental museum of paleontology.

National Building Museum Online (NBM Online): First, for those who aren’t familiar with it, can you describe the Accidental Museum of Paleontology?

Christopher Barr (CB): It is a website that identifies and discusses fossils that can be seen in within elements of buildings and other structures in Washington, D.C. There are fifteen detailed discussions of buildings and fossil stones (and one “living fossil”), which identify the fossils, discuss what the animals were like when alive, and other details about the past environment and how the stones came to be in D.C. There are also some less detailed descriptions of another two dozen or so buildings around the city with visible fossils. Because the fossils span a vast range of geological time and because the remains of so many different ancient environments can be seen, the website presents the buildings as if they were exhibits in a vast, city-wide museum of life during the past half billion years.

Ammonite shell fossil, approximately 150-160 million years old, in a column flanking the entrance to the Reptile House, National Zoo. Photo by Judith Barr.

NBM Online: When and how did you realize that buildings in Washington, D.C. contain visible fossils within their structures?

CB: I have lived in D.C. since 1979, and I do a lot of walking around the city. In 2002, my law firm moved to a newly renovated downtown building that was suddenly full of visible fossils. I researched those fossils and about that same time began to notice other fossil-bearing stones in structures around town. I had been aware that there were fossils in some D.C. buildings from newspaper articles, but I started to actively look for them around town, and more deeply researched the references to them in newspapers and magazines.

NBM Online: What’s the most surprising thing you’ve encountered in your observations of the stone and other building materials of Washington’s architecture?

CB: I was surprised by how common and widespread the fossils are. When I first began to do the research, I thought that there might be six or seven good examples around town. Instead, I found far more fossil-bearing stones around the city. I even found a building downtown with fossil snail shells in the elevator walls! Also, because the fossils are not just the product of a single past style of architecture, more buildings with fossils are built up every year or two. The website now has more than three dozen examples in the “galleries” and “exhibits,” but I have found at least eight or nine more buildings to discuss since uploading the website, and I hope to expand the website to include them.

The spherical/oval shapes (fossils of algae) and the two tall snail shell fossils to the right of the ruler, are approximately 55 million years old and are in the walls of the former Latter Day Saints church at 16th and Columbia Road NW. Photo by Christopher Barr.

NBM Online: Why did you decide to create the website to document these fossils?

CB: After I looked into the massive display of fossil shells at Mitchell Park near Dupont Circle (one of my children’s favorite parks), I assumed that someone must surely have written up an account of them. But I could find no reference to those fossils, and, apart from a few scattered references in a U. S. Geological Survey pamphlet and in the writings of former local geologist James O’Connor, very little was published regarding the fossils visible elsewhere in the city. Also, the few references in print did not describe how to identify the fossils, what the ancient animals looked like when they were alive, or why they can be found now in the built environment. It seemed to me that someone should gather up the information and make it available to the public. I am not a geologist, but I studied geology in college and can read geological reference works and pose questions to geologists. Perhaps most importantly, I cover a lot of ground regularly walking around the city and its buildings. So, I decided to set up the website.

NBM Online: What’s the oldest fossil you’ve found? And the most recent?

CB: The oldest fossils discussed in detail on the website are the worm burrows in the National Museum of the American Indian and the fossils in the floor of the Arts and Industries Building, which are both roughly around 480 million years old. However, I am researching an earlier fossil, the skolithos trace fossils visible in a scattering of pavement stones in front of the Lincoln Memorial, which appear likely to be stones from the Cambrian period—older than 500 million years. The youngest fossils (so far) appear to be the algae and shell fossils in the former Latter Day Saints church by 16th St. and Columbia Rd. NW, which were deposited in the floor of a huge freshwater lake in Utah and vicinity approximately 55 million years ago, at the dawn of the “Age of Mammals.”

Worm burrow (the large, necklace-like structure) approximately 350 million years old, on the Indiana limestone of the retaining wall for the Frances Perkins Building (Department of Labor) on the east side of 3rd St. NW. Photo by Judith Barr.

NBM Online: focuses on the buildings of Washington, D.C. Is Washington unique in this regard—as a city does its architecture contain more visible fossils than other cities?

CB: Washington is not unique, and many other cities have fossil displays. Many, many cities and towns across the U.S. have buildings with Indiana Limestone, which is a fossil-bearing stone discussed in detail on the website. Close to home, there is a geological guide to Baltimore that describes some fossil-bearing stones in its downtown. I have seen fossils in other cities, for example on a trip to Orange County, California, I found many large fossils in the walls of the John Wayne Airport. Once you know what to look for, fossils can be found in numerous places. But Washington does seem to have an unusually large and varied collection.

NBM Online: Are you aware of efforts to document the fossils in any other places?

CB: There are a number of “geological walking tours” available online and in print for other cities and locales, although few focus exclusively on fossils and signs of ancient life. The website provides an illustrative list in its “About” section. There is also an interesting book, Stories in Stone: Travels Through Urban Geology by David B. Williams, which does not primarily address fossils, but does explore the background of building stones in American cities.

NBM Online: Are the fossils that one finds in Washington buildings intentional or accidental? Meaning, are the architects and builders working on buildings aware that the stone they’re using contains fossils?

CB: Architects are aware that the building stones have fossils, and one of the most common types of natural stones used in construction is limestone, which architects know are generally formed of biological remains (even if you often cannot see distinct fossils in a given type of limestone with the unaided eye). I am sure that there are exceptions, but architects do not usually seem to be focused on the age or identity of the fossils or the environment in which they were deposited, they are usually more concerned about other characteristics of the stone. The geological origins of the stone and the nature of the fossils do not seem to play a role in the selection of the stones, as a general matter. However, there may be some exceptions. The entrance to the Reptile House at the National Zoo is framed with a stone from Spain that is Jurassic in age and displays the shells of squid-like animals, ammonites and belemnites, directly under a mosaic of a Jurassic-era dinosaur (Stegosaurus). It was designed by the noted artist Charles Knight, who worked on the Reptile House shortly after studying in Spain. Is that likely to be a coincidence? Also, the use of “Champlain Black” stone, with its large, visible snail fossils in the floor of the Arts and Industries Building, which was the Smithsonian’s first museum of, among other things, natural history, may not have been accidental. Generally, though, it seems that architects choose the stones for their visual impact, texture, and other factors, but not very often because of the particular fossils.

NBM Online: Have you heard from any architects or builders who have seen their buildings documented on your site? If so, how have they reacted to learning about the fossils that you identified? Any surprising reactions?

CB: I have not received much feedback from architects. Some have found the website or its concepts interesting, but I am not certain that many architects are familiar with it. I always look forward to architect perspectives.

NBM Online: What do you think people can learn from a close look at the fossils on architecture?

CB: First, I think that it is worth learning that with a little background, anyone can identify visible reminders of life hundreds of millions of years old throughout the city—that windows on ancient life are accessible to anyone, not just in museums or classrooms, but throughout the fabric of the city. Second, I think it is fascinating to learn that the fossils can tell an observer much about the environment in which the ancient animals lived. For example, the tiny, broken fragments of shells that generally constitute the Indiana limestone do not seem as impressive as some of the large intact fossils. However, they illustrate what the environment was like in Indiana, 350 million years ago, when it was a shallow, warm sea, with a sand-like floor made up of countless fragments of shells and other remains, moved by currents and waves. You can still see signs of waves and the actions of currents in the walls of the city. That is why I think of the various displays as not just being a list of building stones with fossils, but as exhibits in a city-wide museum of paleontology, the study of life in the distant past.

NBM Online: Have you found any fossils on the National Building Museum itself? Or maybe nearby?

CB: The National Building Museum is a wonderful structure, but I have not seen any visible fossils there—at least not yet! Across F Street from the Museum, though, there are many fossils in the National Law Enforcement Officers Memorial. The low curving walls that hold the memorial names of fallen officers are built with a Canadian stone that contains fossils approximately 430 million years old, from a part of southern Ontario when it was a shallow, warm sea with reef communities. I am still researching it, but I look forward to publishing a detailed account on the website. Not too far away, in the walls of 600 Pennsylvania Avenue NW, on 6th Street, there are some very nice brachiopod shell molds, too.