Tag Archives: science

Advanced but still Primitive

Posted on by
Reply

This story about evolutionary hardware design was indeed, as the URL indicates, a damn interesting read. The thing that struck me the most was that the design the evolutionary algorithm came up with didn’t work on other chips of the same type, just on the chip on which it evolved. The minute differences between different chips of the same type are negligible if their use is limited to things we currently understand, but if the only constraint is the laws of physics then the solutions that evolve are so complex and out of the ordinary that, were we to understand them, our advanced tools would probably seem like sticks and rocks.

Making Charcoal

Posted on by
Reply

A long time ago I read an article that peripherally mentioned making charcoal at home. I couldn’t do whatever it was that the article was really about (probably forging swords or casting rocket nozzles from aluminum or something), but I could make charcoal. However, I never actually did anything on this since I live in Chicago and have no yard where I can burn things for hours on end.

Then last month I heard something about an episode of “Dirty Jobs” where he worked in a charcoal factory, and the process was described as basically putting a sealed container of wood in a fire so that it partially burns, but not completely. I was already planning a camping trip soon, so I decided to give it a shot there.

When I got there, I found a log and sawed off some 1 inch rounds, then chopped it into pieces a little smaller than my palm. I put about two gallons of this in a 5 gallon metal bucket. Then I turned it upside down so it was more or less sealed with the earth and started a fire around the outside. I had trouble getting a decent fire going and the fire pit was probably too small to allow the size I would need, but I set it going nonetheless and left it to burn for about 6 hours. When I returned, I pushed the fire aside and lifted the bucket to find … warm wood. The fire wasn’t nearly sufficient to char it all. I found a few pieces that were charcoal, but this was definitely a failure.

So I tried to figure out where I went wrong. The careful reader might notice that earlier I said I read “something” that mentioned making charcoal, then I heard “something” about a show that mentioned making charcoal. Nowhere did I say I read instructions on how to make charcoal. So step 1 for next time, read instructions. I found a couple good articles on the process. The first describes the science of charcoal pretty well, and the second describes the rig much better with bigger pictures. The second also has an interesting feedback loop mechanism where the wood is heated by burning the hydrogen, oxygen, vaporized alcohol and tar that are driven off in the heating process, ensuring an almost perfect heating duration every time. These rigs look a little more complicated than I’m able to do at the moment, but there will definitely be a charcoal round 2 at some point in the future.

The Beverly Clock

Posted on by
Reply

The beverly clock has an ingenious power source. It has a sealed container of air that expands and contracts with temperature differences throughout the day. I’m envisioning a sealed plastic box with a hole cut in the top, and a flexible material over the hole (like a balloon). This material would be connected to a toothed bar interlocking with a gear, connected to a pulley over which the weight and chain that normally run these clocks hangs. The toothed bar only grips the gear in one direction, and when it does it turns the gear/pulley and winds the chain. When the temperature and therefore the pressure of the air in the box fluctuates, it moves the toothed bar up and down, winding the chain. This means that the natural behavior of the environment winds this clock.

It would be difficult to get much productive power out of this setup, but it’s a novel approach to the problem and might be worth keeping in mind.

Materials: The Most Important Engineering?

Posted on by
Reply
I’m watching “Ancient Discoveries: Machines of the East” on Discovery and as usual, there’s some amazing things those ancient inventors came up with. I just saw a device that pours a fixed amount of water at a fixed interval. It used a siphon and a float based valve like that in a modern toilet. The show said this showed an advanced knowledge of differential pressures, which is used today to make jet engines. Was the only thing stopping them from making jets a lack of the materials that could withstand those forces?

There’s seems to be a first key invention that starts a field of science/engineering, like the discovery of the wheel to mechanics, electricity to electronics, etc. But beyond that, could it all be a matter of making the “things” of your discipline out of lighter, stronger, or other interesting materials?

This idea is just off the cuff, I’d like to hear some comments either way.