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Imaging the Codex Xolotl and Mapa Quinatzin

Imaging the Codex Xolotl and Mapa Quinatzin at the Bibliothèque National de France, Paris, 14-15 June, 2016

Written by Jerome A. Offner, Ph.D, HMNS Associate Curator, Northern Mesoamerica

On June 14 and 15, Dr. Antonino Cosentino of Cultural Heritage Science Open Source and I were able to carry out technical photography of the Codex Xolotl and Mapa Quinatzin at the Bibliothèque Nationale de France, Paris (BnF).  Permissions, facilities and staff time were arranged by Laurent Héricher, Chef du service des manuscrits orientaux, Département des Manuscrits of the BnF.  This was no easy task and we express our appreciation for the extensive effort and work he put into these arrangements, particularly in the midst of a multiyear renovation of the site Richelieu, where the documents are kept. Loїc Vauzelle, a graduate student at the Sorbonne, travelled from central France at his own expense to assist, and John Hessler, the Kislak Curator of the Library of Congress also happened to be in Paris and provided expert aid and observations as the process went on.  In addition, Dr. Marisa Álvarez Icaza Longoria of UNAM, who was at the BnF traveling on a fellowship, contributed valuable ideas. She had just participated in the Oxford conference “Mesoamerican manuscripts: new scientific approaches and Interpretations,” held 31 May to 2 June, 2016 which included several talks on imaging indigenous Mesoamerican documents.

The project had been scheduled weeks in advance, but emerging problems nearly led to its cancellation.  The Seine was at or out of its banks in Paris as part of the worst flooding in decades.  The Louvre was moving some of its holdings out of danger.  Certain sites of the BnF were closed.  France was also hosting the 2016 UEFA European Football (Soccer) Championship and Air France pilots began a strike on the day before my flight from Houston to Paris.  Nevertheless, we were able to complete the project and Paris began to resemble its familiar beautiful self at just about that same time. 

Seine receding from flooding at Île de la Cité,  16 June, 2016

Seine receding from flooding at Île de la Cité, 16 June, 2016

Notre Dame, in evening light, June 16, 2016, as the skies began to clear

Notre Dame, in evening light, June 16, 2016, as the skies began to clear

At the BnF, site Richlieu, we were provided with a meeting room with two windows that we were able to cover with two layers of black plastic bags secured by green painter’s tape. For others who may be faced with a similar situation,  it is worth noting that not one but two layers of these already two sided bags were needed to block the summer light sufficiently. Also, the BnF was happy to see that the painter’s tape left no marks on their walls upon removal. The meeting room door turned out to be light proof around its edges and needed no special attention. The room had only a standard meeting table, the height of which unfortunately could not be adjusted. 

We were able to capture four types of technical images for these Aztec pictorial documents.  Antonino Cosentino used a modified full spectrum Nikon D800 digital camera, sensitive to the spectral range 360-1100 nm, along with different lighting sources and filters to obtain images that we can designate in this way:

VIS (visible)
IR (infrared)
UVF (ultraviolet fluorescence)
UVR (reflected ultraviolet)

Because of the table height, we had to shoot at an angle, but Antonino made the best of this by making the IR images do double duty also as RAK images. 

Preparing to acquire images from Codex Xolotl X.020

Preparing to acquire images from Codex Xolotl X.020

Dr. Cosentino focusing in on Codex Xolotl X.050 and X.060

Dr. Cosentino focusing in on Codex Xolotl X.050 and X.060

Technical photography documentation of the manuscripts.

What do these designations for types of photography mean, and how are the images described by them acquired?

VIS is used here for light in the visible spectrum, or the portion of the electromagnetic spectrum that is visible to the human eye. A typical human eye will respond to wavelengths from about 390 to 700 nm. In the procedure used for the documents, light, provided by fluorescent tubes, reflected off the surface of the document and passed through an X-Nite CC 1 filter which blocked infrared wavelengths before entering the lens and camera.  The filtered light was then captured by the 36 megapixel CMOS sensor in the Nikon camera. 

IR is the designation used here for infrared photography.  In this case, a Heliopan RG 1000 filter was placed over the camera lens to block visible light while allowing infrared radiation into the camera. (Remember here that infrared radiation has longer wavelengths than visible light, while ultraviolet radiation has shorter wavelengths).    As mentioned, these IR images also served as RAK images, meaning that the document pages were illuminated by an infrared source at an oblique angle.  Although the angle we used was only slight, the images captured provide a great deal of information on the surface topography and relief of document pages. 

UVF imaging picks up visible light emission excited by a UV source (UV-LED) that is used to illuminate the document.  As the surface is illuminated, certain materials fluoresce—that is, the material absorbs some of the UV radiation that falls on it and emits visible light.  The photons which are then emitted from the document have longer wavelengths that fall into the normal visible light spectrum.  Not all materials fluoresce so this method can be a valuable tool for distinguishing materials, and for seeing certain materials more clearly, such as European iron-gall ink glosses (see below). For UVF, two filters are placed in front of the camera—the X-Nite CC 1 filter mentioned above, and a Baader UV/IR filter.  These filters work together to create a spectrum window that allows just the visible wavelengths produced by the UV-induced fluorescence into the camera, while blocking wavelengths of light outside the visible spectrum.

UVR (reflected UV) imaging is simpler.  The document is illuminated with UV light and the camera records the reflected light through another spectrum window created by the X-Nite CC 1 filter and a B+W 403 filter which allows UV waves into the camera. UVR photography is also another helpful tool for assessing surface topography and roughness. 

The images are taken sequentially without moving the document and can therefore be assembled into spectral cubes in Photoshop through the use of layers.  Using features of this program, and harnessing the human eye’s exquisite sensitivity to detecting change, the various layers can be compared using a method not unlike the blink comparator that was used by Clyde Tombaugh to discover the dwarf planet Pluto in 1930. 

The filter set used for the examination of the manuscripts.

The filter set used for the examination of the manuscripts.

Understanding how the images are acquired helps us understand what we are seeing but also helps us develop methods to uncover or clarify details in these nearly five hundred year old manuscripts. Examining the surface of the images is also not unlike examining the images sent back by NASA planetary probes.  Below, the ice rafts on Jupiter’s moon Europa are seen side by side with rafts of “plaster” (gypsum, chalk, we still need to characterize this material) from the surface of the Mapa Quinatzin.  Many, but not all, Aztec manuscripts were painted after a layer of “plaster” had been applied on top of indigenous amatl (amate) paper.

The filter set used for the examination of the manuscripts. spacecraft on February 20, 1997, from a distance of 5,340 kilometers. Image Credit: NASA/JPL/ASU

The filter set used for the examination of the manuscripts. spacecraft on February 20, 1997, from a distance of 5,340 kilometers. Image Credit: NASA/JPL/ASU

 

Mapa Quinatzin, leaf 2, upper margin

Mapa Quinatzin, leaf 2, upper margin

We need to examine our images as carefully as NASA, JPL, and ASU examine their images, bearing in mind that it is considerably easier to acquire new images of the Mapa Quinatzin than of Europa. 

In our case, let’s compare the VIS image with the IR, UVF and UVR images.

four-squares

In this example, the damaged plaster fragments are seen well in VIS and UVR, while the IR image more accurately depicts the folding and flexing of the supporting indigenous amatl paper, and the UVR images shows mostly disturbance in the underlying amatl paper. 

Every landscape we encounter in the two documents that we imaged has the potential to teach us something new. For example, a detail from Mapa Quinatzin, leaf 3 helps us read the alphabetic gloss in European ink better than it has been read for centuries. Indigenous ink, composed of carbon black, is far more durable and less damaging to indigenous documents.  The often corrosive European iron-gall ink happens to absorb UV radiation and so UVF can be a useful tool for reading alphabetic glosses on these documents because of the contrast with the support (amatl paper) that is generally brighter (because it fluoresces).  This section of the manuscript (below) was unfortunately trimmed during its long history and the meaning of this particular scene, showing a man conversing with someone in a building, along with a man punished by strangling, has remained obscure. 

Mapa Quinatzin leaf 3 records a few Aztec legal rules along with cases of judicial corruption and their punishment. It is not just a list of rules but instead a fragmentary statement of precontact Aztec Texcocan jurisprudential thought, most likely presented, in this case, for European inspection.  Such jurisprudential thought continued well after contact, and involved such issues as how Aztec legal process should be conducted and how certain cases with certain details should be decided and punished.  Aztec jurisprudence was the product of sophisticated schools of thought over many years.   

four-squares-2

In this set of images of a small part of Mapa Quinatzin, leaf 3, the UVF image is improved and rendered legible by the fluorescing of the support (the amatl paper) in contrast to the dark European iron-gall ink in the gloss.  The Nahuatl text in alphabetic form that is revealed, of course, explains only a tiny portion of the meaning of the images: the indigenous Nahuatl graphic communication system was capable of communicating far more than mere alphabetic text could in a given amount of space.  Nevertheless, what little the alphabetic gloss says helps us correlate the image with other lengthier dependent alphabetic texts, especially those of the expert early ethnographer and historian Ixtlilxochitl (1975), and yields enough information to change our understanding of the structuring of the indigenous content of Mapa Quinatzin leaf 3 and of Aztec jurisprudence as a whole.

The landscape provided by the new images is not as large as Jupiter’s moon Europa, but it is a significant undiscovered country that will provide many more surprises as it is examined.  What was unknown proves again to be only temporarily hidden, and more things that remain unknown will hopefully be revealed through these images or through carefully designed new images and imaging techniques. 

 


More about Jerome A. Offner, Ph.D, Associate Curator, Northern Mesoamerica

Jerome A. (Jerry) Offner began working as a volunteer with the museum in 1984 and curated two exhibits on aspects of the Americas in the 1980s. Jerry is an expert on the Aztecs of Mexico, their history, culture and overall graphic communication system, including their writing system.

In 1983, Jerry “wrote the book” on the Aztec legal system and has continued to conduct research and publish articles through the present day on topics including religion, economics and history. He specializes in the beautiful and colorful “codices” or native pictorial documents from before and after the Conquest in 1519 AD. Currently, he is assembling a team in Europe to investigate the greatest of the Aztec pictorial histories—the Codex Xolotl from the city of Texcoco, which reports on many events of the remarkable life of Nezahualcoyotl who ruled that city 1431-1472 AD. This history, kept in the Bibliothèque Nationale de France in Paris, illustrates in considerable detail more than 260 years of history before 1431 AD on eleven pages and three fragments made of native paper. It records the migrations, invasions, wars, marriages, births, and lives in the histories of the many different peoples who came to be known as the Aztecs in what is now the central part of Mexico.

Jerry is also an expert in contemporary masks and textiles of Mexico, with additional interests in Africa and the ancient Mediterranean. He read, writes or speaks English, Spanish, French, Latin, ancient Greek, and classical Nahuatl, the language of the Nahua (Aztecs) of Mexico.

“Museums are for the adults in children and the children in adults,” says Jerry. “Most of us remember our first visit to a museum and how the entire day seemed to go by in a flash. We also remember our children’s first visits to museums. Museums are essential in providing hands on experience and interaction with actual objects in our increasingly virtual, digital world.

They anchor us to what is real and at the same time provide inspiration for childhood intellectual development as well as lifelong learning.”

Jerry received his B.A. in 1972 from the University of Chicago and his MPhil and PhD from Yale University in 1975 and 1979. He was been awarded grants by the National Science Foundation, the Doherty Foundation, as well as the Fulbright program. His book was awarded the Howard F. Cline Prize in 1985.

He is active in presenting papers at professional meetings, both in English and Spanish  Modern Texcocans remain fiercely and justifiably proud of their long history.  On September 2, 2016, he will give the “conferencia magistral” within the at the Tercer Coloquio de Historia Regional de Texcoco, in the modern city of Texcoco 2016, within a few hundred meters of the sites of some of the events depicted in the manuscripts included in the blog post.  He will be presenting important new findings based on the images newly acquired in Paris.

Happy National S’mores day!

Happy National S’mores day! Do you love s’mores but don’t have a campfire to make one? Try these great ideas from Café Natalie, one of our exclusive Museum caterers.

Did you know these delicious treats are named literally for “some more”?

smores 1

Campfire Cones

1 Cup Mini Marshmallows
1 Cup Chocolate Chips

  • Mix marshmallows and chocolate chips and fill cones
  • Wrap cones in foil packet and place on the top shelf of grill away from heat and cook for 3-5 minutes

smores 2

S’mores Crepes

1 Cup Flour
2 Eggs
1/2 Cup Milk
1/2 Cup Water
1/4 tsp Salt
2 tbsp melted butter
1 cup marshmallow creme
1/2 cup chocolate chips

  • In a large bowl, combine flour and eggs while slowly adding in milk & water
  • Add butter and whisk until smooth
  • Head a lightly oiled small pan or griddle over medium high heat
  • Ladle batter into pan and spread batter into thin layer
  • Cook for about 2 minutes on each side
  • Allow crepes to cool before spreading a thin layer of marshmallow creme and adding chocolate chips
  • Broil for 1-2 minutes and fold before serving 

Our exclusive full-service caterers are trained in the policies and procedures of the Museum – making your event-planning process effortless. Each caterer is full-service and can customize your event to meet your specific needs. Learn more…

National Watermelon Day

Written by A Fare Extraordinaire, one of our Museum’s exclusive caterers.

Watermelon Tomato Feta Salad

Happy National Watermelon Day! A Fare Extraordinaire is excited to celebrate this amazing fruit (and vegetable) with you. In honor of this day and the last month of summer, we would love to share some facts, tips and tricks to this refreshing treat.

Watermelon Refresher

TOP 10 WATERMELON FACTS

  1. The first ever recorded watermelon was found 5,000 years ago in Egypt.
  2. There are over 300 varieties of watermelon in the US and up to 1,200 varieties world-wide.
  3. The watermelon is the most consumed melon type in the United States.
  4. The largest recorded watermelon in The Guinness World Record book weighs in at 350.5 pounds.
  5. The watermelon is cousins to the cucumber, pumpkins and squashes.
  6. The watermelon grows from a vine-like flowering plant.
  7. Because the watermelon is cousins to these vegetables as well as being a sweet, seed-producing plant, it is both a fruit and a vegetable.
  8. Watermelons are 92% water.
  9. The watermelon is 100% edible. You are able to eat the entire rind as well as the seeds.
  10. The seedless watermelon was invented only 50 years ago.

Melon Crab Poke1

Our exclusive full-service caterers are trained in the policies and procedures of the Museum – making your event-planning process effortless. Each caterer is full-service and can customize your event to meet your specific needs. Learn more…

Archie the Wandering T. rex Goes on a Road Trip

Archie’s blog written with the help of Victoria Smith, HMNS Assistant to the President

Hi! It’s me, Archie the Wandering T. rex! After seeing the National Parks Adventure 3D giant screen movie and spending time at National Parks Photography Project exhibit, I got inspired to go on my own adventure. Fortunately, I was able to hitch a ride and head out on the highway, looking for adventure, or whatever comes my way.

I got my kicks on Route 66

I got my kicks on Route 66

The epic road trip went across 3 states and 8 national parks. I was excited, but it took 2 days just to get out of Texas!!! We finally made it to New Mexico and our first National Park–El Malpais National Monument. Although the name means “bad place”, it was quite beautiful there. A lot of these formations started in the Cretaceous period, so I was amazed to see what happened in the last 65 million years!

I am the kind of dinosaur who like to make the most of my travels, so when I heard about the Junior Park Ranger program, I said, “Sign me up”!

I think I look pretty good in uniform, don’t you?

I think I look pretty good in uniform, don’t you?

Speaking of catching up on the past million years, I had an unexpected family reunion at the Rainbow Forrest Museum in Petrified Forest National Park. I know what you’re thinking: “Archie, the Petrified Forest features reptiles from the Triassic Period, and T. rexes weren’t around till the Cretaceous!” Well, my mother raised me to respect my elders, and if these ancestors are a few million years older than me, I’m still going to stop by and say hi when I’m in town.

Why yes, I did feel at home in the Painted Desert!

Why yes, I did feel at home in the Painted Desert!

Cousins!

Cousins!

The next day was the big day—the Grand Day, if you will. I got to raft on the Colorado River, and they even let me pilot the boat for a little bit. Since the river runs through the arid climate of Arizona, early Native American tribes settled in the area. We disembarked and viewed the petroglyphs on the canyon walls! The Grand Canyon itself was so amazing, I forgot to take pictures. All I can say is that everyone who has the opportunity should go visit! It was a reminder of what a wonderful world we do live in!

Cool art, hot rocks!

Cool art, hot rocks!

After that, the trip headed south—literally! Even though Montezuma’s Castle wasn’t built for royalty, it was impressive to see the cliff dwellings from hundreds of years ago. (But they want to tell a dinosaur about ancient? Please!) Saguaro National Park was also a spectacular site, thick with cactus that can even poke a T. rex. I didn’t realize how tall they got—they can be as tall as a T. rex is long! That’s 40 feet. I never thought I’d be intimidated by a cactus!

Since dinosaurs prefer warm environments, I’ve never really tried winter sports. Imagine my delight sledding on the sand dunes at White Sands National Park! On this trip, I also found out that you can get a National parks passport and get stamps at every stop. I have so many now!

Gotta catch ‘em all!

Gotta catch ‘em all!

When we went back through Texas I thought we were heading home, but it turns out El Paso is closer to San Diego, California than it is to Houston, Texas. No wonder it took two days to leave the state! The Guadalupe Mountains is the highest peak in Texas, and it contains Permian reef. Of course I felt so at home out there. This is a dinosaur dream trip!

We went from the highest peak in Texas to the low parts of New Mexico, and descended into the caves of Carlsbad Caverns. In the evening, I got to see some of the cave residents, when all the bats came flying out at dusk! There are over 400,000 Mexican free-tail bats living in the cave, and they are all hungry for mosquitos. I love bats!

T. rex trying to spelunk

T. rex trying to spelunk

Unfortunately, all good things must come to an end. After driving around for 3,000 miles, it was sure good to be back at HMNS . . . until I get inspired by the next exhibit. The Bill of Rights is coming soon! Does anyone want to do some research in D.C.? Road trip!!!