Aaron Antrim’s blog

11 July 2006

A note on the photos on this page: if you click any photo, you will go to a larger view of the image in the Parras 2006 online gallery, where you can check out other photos. Unfortunately, there are very few photos of me, because I have posted most of the photos we have in our group’s gallery. I’m working on changing this.

I keep getting more and more behind on my blog posts, but I want to get it all in, so I’ll need to step it up a bit. After our program visited General Zepeta, we began a natural building unit, which meant getting out of our classroom and getting covered in the muddy clay substance which is used to make adobe bricks. By the end of the unit, everyone had blisters on their hands. Many had hurt their feet, and were feeling glad for getting their tetanus booster shots before they came. Even though it was hot and exhausting at the time, now everyone misses building adobe bricks.

To make adobe, you start with a wet mixture of sand and clay. It was unnecessary for us to mix sand and clay because the soil which was delivered had a lot of clay in it already. We let our mixtures sit overnight in a Mount Saint Helen-shaped mound, the crater filled with water, so that the clumps would dissolve. The next day, we mixed the material with our feet, and added in paja, or straw, which provides the tensile strength to hold the large adobe bricks together as one unit when they are dry. It’s not 100% necessary in areas like Coahuila, where there is little seismic activity, but still a good idea. The completely mixed substance is then “cut” using hoes, which chops up whatever dry clumps might still be in the mixture, and pulled away from the pile to be loaded into wheelbarrows to be hauled away and made into bricks.

The forms used to make Adobe are called adoberas. They are filled with the adobe “dough,” as I’ll call it here, which is pounded and kneaded in so that it fills all the corners without structurally-unsound air pockets. If the adobera is wet and clean when the material is put in it, it will lift right off after all the material has been placed in it, kneaded, and the top has been smoothed off. What is left is a wet adobe brick in the shape of a brownie, about four inches tall by one foot wide by one and a half feet long, which will dry in a few days. For the structure we were aiming to build, which, unfortunately, will not be seen through to completion while we are here, 1,400 of these very large and heavy bricks are necessary. We were able to make about 1,000 bricks. The remaining will be purchased from an adobe brick maker.

One of the reasons Adobe is an appropriate technology is because of its thermal properties. The old houses here are exceptionally cool and comfortable during the day, without air conditioning, because the Adobe bricks slowly absorb and hold heat throughout the day, heat which would be making the interior of the home uncomfortable if it wasn’t held by the adobe bricks. By the evening, the adobe walls will have absorbed a significant amount of heat. As the air cools, the opposite heat exchange that occurred during the day will occur, and the adobe bricks will cool as they let off the heat they absorbed during the day, warming the interior of the house during the cool night. Recognizing the utility of these thermal properties requires taking a different approach than is conventionally taken in U.S. building codes, which recognize only insulative material. Adobe, since it transfers and absorbs heat, is not insulation, but thermal mass. Even in Mexico, where adobe had been a popular building material for a long time, it is not impossible to get a bank loan to build an adobe structure. As to why this limitation is in place, I am not sure.

Another reason Adobe is an appropriate technology here is because the materials for it are all locally available and so they don’t need to be imported using fossil-fuel powered transportation. Also, making adobe employs local people. Frequently, appropriate technology implementations are less expensive in terms of materials, but require more labor, and adobe exemplifies this. The adobe bricks are labor-intensive to build, but require inexpensive materials. Especially because of the availability of inexpensive local labor, adobe seems especially feasible and appropriate here. For more on adobe, check out the adobe category on Appropedia, the site our AT program is using as it’s main information platform.

This point about appropriate technology and its high labor need is an interesting and necessary discussion. I admit I am obsessed with efficiency, not only in my own life, when I will confess I have read at least one of those books with someone wearing a suit on the cover telling you how to squeeze more out of your time (it’s really quite good, Getting Things Done, by Greg Allen, a business productivity expert who emphasizes “mindfulness,” a persuit he borrowed from eastern traditions). I will become instantly frustrated and critical if I work with any organization which I think is running inefficiently, and employs too many people and is therefore wasting public money or overcharging their customers because of high staff overhead. This is a distinctly American mentality, which I refuse to give up. At the same time I understand the occasional value of labor over automation, which is such an important reoccurring theme with appropriate tech, and it has instructed my behavior as a consumer for a long time now. When I purchase more expensive organic food, for example, I assume that the food is more expensive because of the higher labor overhead, which is necessary because the “less efficient” farm doesn’t use the same petrochemicals which allow modern farms to get higher yields per farmer. However, I assume (I hope correctly) that the organic products I buy not create more safe jobs for farmers, but also are higher quality. Too often, efficiency comes at the expense of quality in the American economy.

One of my favorite examples of appropriate technology is from our teacher Lonny. He compares Blackboard with Moodle, two online learning management systems HSU uses. Blackboard, an expensive commercial product is being phased out in favor of Moodle, a free “open source” solution. The thing is that Moodle isn’t really free, because it requires a lot of technical staff to run it, whereas Blackboard comes with service and support from company. He estimates that the two solutions actually cost the same but posits that Moodle is more appropriate because running it and refining employs local people and builds our local pool of technical expertise and local economy. Since HSU can build their own refinements onto Moodle, and borrow the open source refinements of others, we end up with a higher quality service.

aaron :: Jul.11.2006 :: México :: No Comments »

2 de Julio 2006

After presentations on June 16th, the HSU crew and a few students and teachers from UTC went to General Cepeta on Saturday to look for/at dinosaur bones and other fossils. T-Rex used to roam these parts, as did a few others whose complete skeletons we saw at El Museo del Desierto in Saltillo a month ago. Those skeletons are truly an impressive sight. T-Rex’s mouth could definitely fit a whole human being if you’re into the whole Jurrasic Park thing. I’ve heard dinosaurs had extremely small brains, especially considering their large bodies, but maybe this is just a bias that has come from those recent Microsoft ads. Anyway, I’m really, really glad I’m a warm-blooded mammal without green scales. Also, the fact about dinosaur brains reassures me for the future of the world: it seems intelligence is destined to win out, or at least out-survive in the end. Or, more likely, the insects will take over.

Seeing dinosaur bones gives suggests something of the essence of the desert. The arid landscape with limited resources for life appears timeless, changing slowly. At the same time, its sudden storms and creatures and plants with various poisons, spines, or fangs, makes it volatile and dangerous.

Outside of the museum at General Cepeta we only saw a few dinosaur bones that archaeologists had neatly uncovered and laid bare. It was actually pretty cool and made me appreciate what archaeologists must do, because the skeletons don’t come all neatly laid out like you see in the museums. We also collected a bunch of rocks with tiny fossils of sea animals and shells at about 3,000 feet elevation.

The walk out there had been about 2km and was easy enough, but the walk back, even though it was easy, gave me a bit of appreciation for the power of the desert to make one uncomfortable, or, in extreme cases, dead. Even though I had brought a lot of water for this small excursion, I drank it all, and started feeling dizzy and weird as I was walking. When we returned to the tiny town, the only bottled water offered for sale was really reused, unsealed bottles of tap water. I ended up drinking some along with a lot of Fanta.

Very ready to cool off around this time, we visited a swimming hole Edgar, an UTC student, knew about. The bus had to navigate some gravel and dirt roads that were in less than great condition. Earlier, too, before we got to General Cepeta, we were barreling down narrow dirt roads. I was surprised and impressed the driver would take our huge bus on those roads.

The swimming hole was beautiful, fed by a small stream. Water cascaded from one medium-sized pool formed by rocks into a larger and very deep pool several feet below it. Above the pool, high rock ledges between 20 and 50 feet above the water allowed some of us to safely free fall into the soft and forgiving green water below. Vegetation surrounded the area, and there were even some cattails which are useful for marsh-based waste-water treatment systems, something that Parras program appropriate tech experts are dreaming of implementing in Parras. The knowledge that this plant species already grows in these parts was a joyous discovery for them.

The mention of waste-water treatment is not incidental to this narrative. The beauty I have described was marred not only by the styrofoam cup and cigarettes floating on the water but by some other foulness in the water, as well. We were told there were almost certainly human urine and feces in the water, but the swimming was so enticing that we couldn’t help but go in. Neither did it keep us from jumping off the rocks, which it might have, because it’s difficult to keep from getting water in your mouth when you go in. I don’t think any of us got sick from the experience, though, but those of us who had climbed on the rocks had minor abrasions which, strangely, were stinging when we got out of the water. Deciding it could only be something frightening in the water making this happen, we applied some antiseptic rubbing alcohol and were on our way.

Seeing this swimming hole’s condition made me appreciate how lucky we are to have many protected and clean natural places in the United States. However, as the most consumptive nation on the Earth, we are probably responsible for more environmental destruction and resource extraction outside our borders than any other nation. And there are plenty of places in our borders, too, which have been ruined, most often places where people who can’t afford to live anywhere else have settled. Yet, at the same time, we’ve done an effective job at protected wilderness as a national treasure for those who can afford to enjoy it. Wow, am I glad that somehow I just happened to end up on one side of the equation rather than the other.

That’s all for now. Hey! When is anyone going to post a comment on my blog? Does everyone just have better things to do, or are you clicking the links in my posts and ending up somewhere far more interesting than where you started?

This post was written on an antique laptop running Ubuntu Linux. Then it was edited and refined on a Macinotsh.

aaron :: Jul.03.2006 :: México :: No Comments »