Although we are, by number at least, 90% bacteria, only recently have scientists with the Human Microbiome Project have just begun figuring out who those bugs are.
[The] trillions of microbes that make their homes in and on us do an excellent job keeping us healthy (crowding out harmful microbes) and sated (breaking down a lot of the food we ingest).
Now that disturbances in this rich microbiome community have been linked to weight gain, inflammatory bowel disease, vaginal infections and risk for infection with harmful microbes (such as methicillin-resistant Staphylococcus aureus, or MRSA), the importance of understanding what makes up a “healthy” microbiome has become even more apparent.
Ms. Wilson’s chemistry class is looking at basic chemical reactions, and today they got to fire an acetylene cannon. When calcium carbide (CaC2) reacts with water (H2O) they produce acetylene (C2H2), which is quite explosive.
CaC2 + 2 H2O → C2H2 + Ca(OH)2
Acetylene is so flammable, because its carbons are held together by a triple bond: when the triple bond breaks it releases a lot of energy (about 839 kJ per mole).
Table 1: Bond strengths of simple hydrocarbons with carbon to carbon bonds
Name
Chemical Formula
Diagram
Carbon to Carbon Bond Strength (kJ/mol)
Acetylene
C2H2
839
Ethene
C2H4
611
Ethane
C2H6
347
The explosion is a result of the combustion of the acetylene:
2C2H2 + 5O2 –> 2H2O + 4CO2
And this whole process — carbide plus water to give acetylene, which is then burned — was used by miners in the early 20th century to make headlamps (among other types of lamps).
A carbide lamp (image via Wikipedia).
The cannon itself is a simple device, made of a 50cm tube of 2-3 inch diameter PVC (sorry about the mixed units), with a screw cap at one end. The carbide grains (about 0.5 g) are placed on the inside of the cap, which is then screwed on to the bottom of the tube. A few drops of water are then added through a small hole in the PVC using a plastic dropper — you can listen for the sizzling to tell if the carbide decomposition reaction is happening. Finally a flame is applied to the same hole as the water. The sock, by the way, is just lightly tucked in near the top of the PVC tube, about 5 cm in.
The explosion was loud, and Ms. Wilson’s sock traveled about 10 meters. It was suitably impressive. I think the student who was the most impressed was the one who had weighed out the calcium carbide, becaues 0.5 grams is really only four or five grains.
Sitting around the campfire and telling stories on the Current River.
Writing is a process. There might not be one single, best, process, but breaking the process into steps is often useful for new writers trying to find their voice. The following steps come from my Middle School Montessori Training a few years back. While I’m not teaching language at the moment, I would like to get my students to write up their experience in the thunderstorm on the river using at least parts of this process.
Step 1: Collect Seeds
Collect ideas for topics to write about. This is why we keep a writer’s journal with us at all times. Anything can be a seed: quotes from books you’ve read; overheard snatches of conversation; ticket stubs; artifacts; rocks; notes about profound experiences (which is what I count the canoe trip in the storm as).
Step 2: Develop ideas
Take a seed idea and write about it. Write fast, write rough. You can fix it later. Write to surprise yourself.
Step 3: First Draft
Use the ideas from your rough writing to make a first draft. This does not mean editing the rough writing, in fact, you should probably put away the rough writing and start your draft from scratch.
Step 4: Revision (the hardest part)
Revision is making the big changes to your writing. Even if you liked your first draft a lot, making big changes helps you see your work in new, interesting ways. Try:
Rewrite in a new genre: convert your memoir, for example into a play, or change the perspective from first person to third person.
Physically cut and paste your story. Maybe the conclusion actually works better as an introduction? Rearrange your paragraphs, rearrange the sentences in your paragraphs. See what works and what does not.
Read out loud, or have someone read to you. As you read you can rearrange the paragraphs (read the last paragraph first, for example).
Step 5: Edit
Now that you have a draft that you like, edit it for spelling, grammar, punctuation, capitalization etc.
Step 6: Polish and Publish
Make your story look pretty. Format your text how you want it, or how it needs to be in your word processing program. Remember, simpler is better. Fancy fonts and colors tend to distract from your story.
Remember that there’s no final version of your story. Writers are always making changes (or wanting to make changes). You can always make changes and, if you don’t like them, revert to the original.
Notes
As an example of how revision can change a story, I have my two versions of our thunderstorm adventure here and here. They’re aimed at different audiences, but you can see that they came from the same source.
The middle school has been studying The Tempest over the last quarter. In order to give students a deeper connection with this Shakespearean play, we arranged for students to experience the titular meteorological phenomenon on our outdoor education trip last week. Since we’re located in the mid-continent, replicating the precise maritime conditions and acquiring the appropriate vessel would have been cost prohibitive. Instead, taking advantage of the local geography and socio-cultural predilections, we improvised by arranging for a series of thunderstorms during a canoe trip in the Ozarks.
In truth, the main purpose of our outdoor education trip was to integrate the upcoming 7th graders and new students into the middle school class. The key advantage of the multi-aged classroom is the opportunity for older students to mentor the younger students, and propagate the appropriate classroom culture and expectations from year to year. But for this to work well requires students to develop strong working relationships and communication skills. The isolation of the trip (no technology) and the coordination required for the tasks we perform (such as paddling a 2-person canoe) greatly facilitate this process.
Despite being drenched, chilled, and a little scared, the group’s performance was remarkable. They endured the worst of the storms, looking out for each other with encouraging words and heartening smiles. They found the strength within themselves as individuals and as a group to keep morale high while on the river. And, when we pulled over, were able to bask in the giddy relief that a good group feels after stressful situations. By the end, they had developed a genuine camaraderie forged by a shared, intense challenge.
P.S. We also did some rock climbing, caving, spent a night on a sandbar, journaled, and learned a bit about geology, hydrogeology, fish surveys, the rock cycle, and some vocabulary (“hubris” was a term, new to many, that was ably demonstrated by the pair who flipped their canoe).
Rock climbing.Spelunking.
P.P.S. Our excellent, invaluable guides on the trip were from Discovery Ministries, which is a religious organization, but they do non-religious programs for groups like ours.
A line of canoes float past limestone bluffs in the midst of a thunderstorm.
The middle school class has been reading The Tempest for language arts this semester. However, I had not quite realized that it was a presentiment of for our outdoor education canoeing trip. And not metaphorically — the group worked amazingly well together — but there really was a massive storm while we were out paddling on the Current River.
Weather map from Wednesday, September 26th, 2012.
On Wednesday morning, two hours before dawn, a cold front heading south from Canada met a warm front coming north out of the Gulf. They met and stalled, pushing waves of clouds and thunderstorms over us from the west.
The first wave hit while we were in our tents; the second during breakfast. One student recounted that his highest point of the trip was when he tasted his first pancake that morning. His lowest point was when the pancake was promptly soaked with rain.
The third wave met us while we were in our canoes.
Searing lightning, flashing across the ridges of the valley. Blinding white. Immediate thunder, roaring straight through the ears, reaching in, taking the breath, grabbing at the soul. Drenching rain — cold and hard — a deluge. One of our guides described it, afterwards, as a religious experience. I think I know what she meant.
Our guide (Ronnie) takes refuge under an overhang during the height of the downpour.
But the kids were awesome. Drenched, cold, and scared they paddled on. I was with a small group that was bringing up the rear. We were far enough behind that, for a long time, I could not tell how the students in the lead were responding. Especially when, at the height of the downpour, the lead group went around a bend in the river and out of our line of sight.
And there was a loud cheer.
I knew they were with our lead guide (Leah), whose skill and competence had already been demonstrated earlier in the day when one of the canoes had flipped. Yet, one always worries about how kids will react in stressful situations. Following the current around a gravel eyot, however, I heard a loud cheer. There was the line of canoes, pulled over waiting for us. There were the students, soaked and perhaps a little bit relieved, but with no panic in the cacophony of voices.
When everyone had caught up, we continued on. Eventually, we hit a landing and called an end to the canoeing. Although the rain had stopped it was still cold. So, a few students decided that since the river water was so cold, if they waited in the water, when they came out they’d feel warm. “I’m willing to deceive my body,” they said.
Waiting for the bus.
While we waited for the bus, we talked a little about what we’d been through. Despite the stress — or perhaps because of — there was lots of laughter and a growing sense of camaraderie. I took the chance to highlight some of the quieter voices, those students who tend not to complain or be too excitable, and who took the time to appreciate the beauty and uniqueness of what they’d been through.
While I would not have planned it that way, the storm, our tempest, forged bonds of common experience that will resonate with this group for years to come.
The first raindrops create tiny, concentric, waves that spread out and merge gently over space and time.
Notes
Infra-red satellite imagery from Wednesday, September 26th, 2012 shows the waves of thunderstorms passing over southern Missouri (yellow dot) very well.
If children live with criticism, they learn to condemn.
If children live with hostility, they learn to fight.
If children live with fear, they learn to be apprehensive.
If children live with pity, they learn to feel sorry for themselves.
If children live with ridicule, they learn to feel shy.
…
If children live with encouragement, they learn confidence.
…
If children live with acceptance, they learn to love.
…
If children live with sharing, they learn generosity.
If children live with honesty, they learn truthfulness.
If children live with fairness, they learn justice.
If children live with kindness and consideration, they learn respect.
If children live with security, they learn to have faith in themselves and in those about them.
