Last Thursday, I gave a presentation at the Science Museum of Minnesota. I was on my out, stepping out of the elevator lobby and into the parking garage, when I was hit by a wave of vomitous stench. The smell turned out to be coming from a not-quite-totally mummified chicken carcass held by Thor Carlson, one of the Science Museum's exhibit developers. It was fairly obvious why Carlson might want to mummify a chicken—there's a traveling King Tut exhibit at the Science Museum right now. But how true-to-history were his methods? And why a chicken, specifically? I called up Carlson this week to find out more about him, and his still-not-quite-totally mummified bird, which he's named Nefertweety.
Maggie Koerth-Baker: Tell me a little about yourself. How did you end up being a guy who mummifies chickens for a living?
Thor Carlson: Previously, I had actually been on the other end of these interviews, as a newspaper journalist. But I've volunteered here for about 10 years. Then, about 5 years ago ... well, with the way the newspaper market is these days I found myself looking for other directions. I do a lot with the Science Buzz section of our website, where we take current science topics from the news and boil them down for a general audience, and that got me into exhibit development.
One of the first projects I worked on was Lost Egypt, a traveling exhibit. While I was working on that, I came across a number of websites that tell you how to mummify chickens or cornish game hens. The idea just stuck in my head and I decided to try it out now that we have another Egypt exhibit. We try to have something on Science Buzz that relates to the traveling exhibit. And we have a history of looking at some of the grosser things in science. For instance, when we had a CSI exhibit a few years ago, Science Buzz took a pig carcass and recorded it on video as it decomposed over several weeks.
MKB: Why mummify a chicken?
TC: The museum has actually received feedback from a number of schools that did this with cornish game hens. They donated the mummified and wrapped hens to the museum afterwards. So we thought, "Let's do a chicken." It's a little bigger. It'll take more time. And we could go to the store and buy one that's already gutted and cleaned. It is taking a lot longer than we expected, though. We've really been reminded that this is something of an experiment.
It's really about education. The kids are learning about Egyptology and why mummification was important and how it might have been done. And one of the things we're finding out is that we don't know for sure all the details of how a mummifier did his job.
MKB: I was really curious about that. How do we know how mummification happened in Ancient Egypt. And how similar is the process of mummifying Nefertweety to those historical accounts?
TC: We end up talking to adults a lot about this. What we know about how Ancient Egyptians did it mostly comes from sections of The Book of the Dead, which is their map of what happens after death and how to get to the afterlife. It has information on different spells and the physical processes for different aspects of mummification. And we also get information on this from things that have been painted in tombs. There are a number of samples that show mummification being done.
One of the big variables [between ancient mummification and what we're doing] are the salts. What they used is a naturally occurring mineral called natron, and you can't go buy at the store in Minnesota. We're following a formula that we think would make up the closest thing to natron. It's one part table salt, two parts baking soda, and two parts sodium carbonate, which is also called washing soda.
MKB: How is making a mummy different from salting food? That's an easy thing to miss when we talk about human mummification, but with this chicken, it almost sounds like food preservation.
TC: It's actually really similar. A human mummy really isn't much different from human jerky. In a lot of ways it's the same thing, using salt materials to draw away the moisture and leave something preserved behind.
MKB: How do you know when it's done?
TC: According to the websites we've read, it shouldn't smell anymore when it's done, and it should be completely firm. Touching the chicken's legs, they should feel like rock, just solid. But, with Nefertweety right now, around the back end there's still some squishy soft places. The softest, thickest places on our bodies are the back end, too, and that would also probably take longest to mummify on a person.
MKB: What has this process taught you about mummification that you didn't know before? It's probably silly, but I was surprised to find that the body stinks while it's being mummified. I guess I'd sort of imagined that the salts blocked that.
TC: We knew it would be stinky, probably. So we put it in a tupperware container under an aquarium hood. But we underestimated the stink. Until about two weeks in, we had been doing the mummification in the visible lab in our collections gallery. But after two weeks the stench was so strong that museum security came to ask us what was going on, because the smell was spreading to other parts of the building. That's when we realized we had to do this out in the parking ramp.
If you think about roadkill, it stinks because the decomposers of society—the bacteria and maggots—are eating at the flesh and releasing gasses and odors as part of that process. Natron is sucking away moisture from the body and it's kind of doing the same thing. The body isn't decomposing. But what the natron absorbs, that's what the bacteria and maggots would have eaten. That stuff has to go somewhere. In mummification, it goes into the natron. Periodically, we've had to dump out all the natron because its absorbed so much and smelled so bad.
We were also surprised by the weight loss of the chicken. It was 3.5 pounds when we started. And it's down to 1.75 pounds now. All of that natron sucking away the moisture inside the tissues has taken away half the chicken's body weight. Also, the chicken flattened out a lot. We don't really know why this happened, but we're thinking that it's because birds have hollow bones. As they lose moisture, the bones are also losing their strength and that's making the big arched chest cavity collapse down. Right now, it kind of looks like it was run over by a car. It's more than just drying up.
MKB: How many days have you been working on Nefertweety?
TC: Today [Tuesday] is 54 days. Typical human mummification took 40-60 days. So that's got us wondering that we're doing something not quite right. You'd think it would take a chicken a lot less time to mummify than it takes a human.
The other thing we realized, is that we've been working on one little chicken for two months, but an Egyptian mummifier would have to have a lot more organization. He'd be working on several different bodies in different stages, all at once. There must have been a concentration of bodies, so mummification probably didn't happen in the center of town. It was probably on the downwind edge of town.
MKB: Once you have a mummified chicken, then what do you do with it?
TC: The ones we get from schools are wrapped up and the kids decorate them. But I'm really pushing for not wrapping Nefertweety, and, instead, showing what a mummified chicken looks and feels like compared to the chicken you buy in the store. I'd love to have it just be something people can hold and touch. People always want to know, what does a mummy feel like? I don't know if we can do that from human health standpoint, though. Maybe we can shellack it.
Thy took the human mummy we have over to children's hospital in St. Paul for a CT scan back on Halloween and the people there said it feels like carrying a skeleton, it's so light.
Hopefully, we'll have a chicken mummy by the end of the week. But i've been saying that for a few weeks now.
Images: Mark Ryan for the Minnesota Science Museum. See more shots of Nefertweety on Flickr.