A really exciting rocket stove project

Recently my buddy Aditya and I built a Winiarski Rocket stove at our neighbor's farm to get a temporary kitchen setup going. (If you don't know the term, a rocket stove is just a more efficient wood-burning stove). There is nothing original about our design -- you can see this design well documented here, along with other designs. I thought I should share our effort anyway to inspire you to build your own. You will see the exciting part soon enough.

We picked this up at our local kabadi-wala for Rs 20. It is fairly easy to cut out the top and the round hole at the bottom with a sharp, pointy knife.

We had also picked up three smaller cans like this for Rs. 5 each. From two of these we removed the bottom as shown. Notice also the flattened edge where the lid used to fit.

We then used this metal snip (easily available in most hardware stores)...

to cut strips into one end of the same two cans.

Then we cut out a hole (same diameter as the previous can) in the third can.  Clearly not a neat job but good enough for our purposes.

 

 

Here are the three pieces assembled. While we were busy with this, I heard a rustling noise from the left edge of the room. I turned around to see a fleeting glimpse of a fast moving snake that instantly took cover behind a broom standing in the corner.

There was no further sound so we assumed that it had no intention of moving out from its new location. With hair literally standing on end, we gathered enough wits about us to pick up the camera and a proverbial 10-foot pole to knock down the broom. The result of the effort shows a clearly panicked creature here. At that point we had no idea whether this was a venomous type.

Finally, after failing to scale the wall, our reptilian roommate was able to see the door and was gone in a flash. We later found out that this was a non-venomous tree snake called the Common Bronzeback, known for its fast movement.

The previous excitement ended up affecting my documentation efforts somewhat and I forgot to take as many pictures as I would have liked. Here, the L-shaped assembly we built earlier has already been lowered into and fitted inside the the oil can and Aditya is giving it an adobe (clay + sand mix) cladding. We expect that after a few weeks of cooking, the tin internals will start to break down but leave behind a nice hollow of baked clay.

Here, the cavity between the Adobe and the outer container has been filled with wood-ash, which forms an insulating layer to keep the heat from escaping sideways. The stove is ready to use.

- Dev

Ain’t About A Simple Bag.

It all started when Mr. Z walked in with plastic bags containing groceries for the day. He is a close relative who I have known all my life. I was visiting his family. I tend to take liberties with them and so asked why they continued to bring plastic into their house, in spite of all the conversations we have had before. Their spontaneous response was that they needed plastic bags to discard their garbage!

This is the story of most households in countless places – people bring plastic in and throw plastic out. I asked the couple to think about the world that their ancestors left behind for them and questioned if they can justify leaving behind a planet filled with non-biodegradable plastic trash for future generations. They said that they didn’t have the time to ponder over such questions and instructed me not to waste my time either. It was quite clear that they won’t take a deeper look at the issue. I decided to prod further since I was not fighting for a personal cause. What baffled me was that, this was a couple who mostly lived waste-free just 30 years ago. Indeed, I often draw inspiration from how they lived back then.When I told them this, they said: “We didn’t throw plastic away because there was no plastic to be thrown away in those days.” So, it was not a matter of choice, and hence there was no value attached to their earlier waste-free lifestyle.

I spent the next few minutes talking about the poor people that sift through garbage, the great pacific garbage patch, the companies that make money selling millions of these plastic bags, the time (thousands of years) that plastic would take to decompose, the toxins that get into the air when plastic is burnt etc. I was curtly told that there was no need for me to get so emotional over a simple plastic bag. But it isn’t just one bag. Their own household, I know, has been throwing away 7–10 plastic bags/wrappers every day, adding up to 2500–3700 plastic bags/wrappers per year! When I mentioned this number, I am sure the enormity of it caused them to flinch a little. But still there was no commitment from their side.

I had no idea how to get past this invisible wall they had constructed around them. All I knew was my heart was racing, my frustration was mounting and  my anger was taking control of me. I was unable to connect with them effectively.. When I became mindful of my current emotional state, I realized that I could ask them to do some mindfulness practice too. I asked Mr. Z to try running an experiment on himself just for one day. I said, “Please carry a few cloth bags with you and use only those. Please indicate your preference to the shop-keepers and if possible let them know the reason. Since you know that your choice is helping the earth, you are likely to feel a certain way about your choice and your action. Please observe the feelings and emotions that get evoked within you”.

Maybe this couple will start seeing garbage with a new pair of lens. If not, I will have to devise another way to reach out. I can’t give up, can I?

-- Hema

Reduction and Backtracking

In an earlier post we had shared how easy it was for Abhi to learn to write Hindi. We later realized that that story (and other stories of our children learning) could be read in a way completely different than intended by us. It could be read as a story of an exceptional child, doing something exceptional. Instead, our intention was to illustrate how easy it is for any child to learn to write, provided the child is motivated and the methodology sensible. This post continues in the same vein and we hope it will not be read in as a story of exceptionalism.

Aparna has always been fascinated with numbers and basic arithmetic, as we wrote earlier. Recently we were surprised when she demonstrated some sophisticated mathematical thinking that was not ever taught.

We occasionally go see Dev’s sister in a different part of Chennai and the bus ride is typically long. During one of these rides, Aparna wanted to do division that involved “big” numbers. So I asked her what 39 divided by 3 was. After working on it for a minute, she came up with the correct answer and was eager to share her algorithm with me. Here is the translated version of it:

“Let us set aside 9 and consider only the number 30 for now. So the question becomes ‘what is 30 divided by 3?’ 30 is a big number for me. So I am going to halve it and the question now is ‘what is 15 divided by 3?’ I know that there five 3’s in 15. Now I go back and use this information to answer the previous question – i.e. 30 divided by 3 must be twice as much as 15 divided by 3, which leaves me with the answer 10. Now I bring back the 9 which was left out earlier. I know that there are three 3’s in 9. So I add 3 to 10 and that is it!”

Weeks later I realized that what Aparna described to me, incidentally, is a problem solving strategy called “Decomposing and Recombining” by G. Polya in his famous work How to Solve It.

I believe that the enormous amount of time and freedom with which she has explored numbers on her own has helped Aparna build the number sense that is depicted here.

-- Hema

Math and Writing

Here is a short account of how my children started to do divisions and how it led to an unexpected learning outcome.

We had found that basic numeracy was easy for our children to acquire, so much so that we hardly remember how it came about. We never really sat down to do math with them. As she went about her daily chores, Hema had always liked to involve the children, and little by little, in the course of talking about things, both the kids acquired a sound number sense along with a good handle on how to add and subtract.

Before we homeschooled, Abhinav went to two different "liberal" schools in California for 3 years, where at the end, he was expected to do some simple addition and subtraction of mostly one or two digit numbers. Abhi was already numerically competent, so none of this interested him. Unsurprisingly, as the other parents and the teacher told us, Abhinav was rather bored in the class and was often creating trouble. However he continued to be fascinated with math and we let him explore his interest on the Khan Academy website.

One day, while playing with an addition/subtraction math practice program on the website, Abhinav, 7 at that time, got curious about a math symbol he hadn't seen before. So he asked me. I said "This is division" and then remembered my own childhood difficulties about learning this, so I added, "This is too advanced for you." He wanted me to tell him anyway, and as I was forced to respond, my sense of responsibility yielded a simple way to present this idea. I said, "6 divided by 2 means we find out how many 2's are in 6." He chewed on this unblinkingly for a couple of seconds and then said, "But you told me this was hard!" He went back online and spent the next hour or so absorbed in playing with the division practice program.

Sometime later, my daughter, Aparna, then 5, wanted to know this division thingy too. By this time I was more willing to question my own assumptions about what was hard, so I gave her the same simple explanation that I had given her brother earlier. And it worked this time as well. She was so thrilled with this new learning that over the next several weeks she would ask either my wife or me for division problems and then proceed to tackle them with relish.

Soon, I was beginning to get bored with this routine and had to think up something new to keep my own interest from flagging. I started making certain formulaic stories that featured a seriously math-challenged dad and his two children, a girl and her little brother (an example will follow). The stories always climaxed with a division challenge that stumped the hapless dad, and then the two kids would easily do the division and present the solution to the astonished dad. In the telling of the story, I would stop it just before the problem was solved. Then I allowed Aparna to have a go at it first, and I remember clearly how her face would be agog, waiting for this moment. She would scrunch up her face in total concentration and then furiously start calculating. And finally when she had the answer, be very tickled by how the dad in the story can find this so difficult. We must have played this game for months and Aparna never got tired of it.

While she had been interested in many things, Aparna had never wanted to write. This situation changed suddenly last year when she picked up a little notebook and wrote a story about the math-challenged dad. The story is reproduced below with Aparna's permission. (Please note that the story has been reproduced exactly, alternate spellings and all.)

So ultimately, what had started as a math activity, ended up becoming an exploration of the writing process.

- Dev

How many autos? (A story by Aparna Jain)

One [day] the father went to a big big parck. With his family. On the way thay had to take 3 buses 2 autos. Instead of sitting he started to count the autos. After they were ther they let the kids go to the playgrond and ther was a session you can make somthing and go sell it so they went ther. The kid's friends had com so the kids played. whith ther friends. This session was about organic food. When it was lunch time ther was organic food so they ate whith everyone. When they went back home the kids asked ther dad what did you count anything today.

Oh! When we wher going ther in the bus I counted the autos weels, 96. How many autos?  Now readers figure out the answer.

Note to non-Indian readers: The "auto" referred to here is a three-wheeled taxi common in India.

My Head On Your Shoulder

Recently, I got on an early morning train at the Chennai Central. Still sleepy, I located my seat and dozed off even before the train had started. But it was not long before my sleep was interrupted by a tap on my shoulder. It was the girl sitting next to me. I heard her ask: “Can I rest my head on your shoulder?”

I was in a second class coach, where the seats accommodate three people comfortably but with no arm-rests in between. She was a young girl, probably half my age, and I could tell she had just got married, bedecked as she was in a silk saree, jasmine flowers, jewelry and mehndi . Her equally young and new husband was sitting on her other side. They seemed like the people of a small town or a village. In such places, it is not unusual for new couples to not interact with each other.

I said yes to the girl’s request. She promptly tilted her head on my shoulder and we both dozed off. After some time I heard a distant voice talking to that girl. Her parents who were sitting nearby must have gotten slightly concerned. They woke her (and me too in the process); she said sleepily, pointing at me “I had asked her”. That was enough explanation, met by accepting head waggles, and everyone went back to sleep again.

It was not until later, when I got off the train, did this event strike me as unusual. This girl’s simple human request illustrated for me a profound difference between the cultures of big cities and villages. She had a straightforward need that I could satisfy, and so she asked. Simply, just like that. No mental clutter of judgments and inhibitions of “appropriate” behavior of “cultured” city folks. Because of this encounter, will I be a little less inhibited when I am presented with similar opportunities of human interaction? I hope so.

-- Hema