Which is kind of amazing. The magnetic field is produced by some remarkable result of the convection of molten hot iron alloys in the core of the Earth. Kind of hard to really get your head round if you’re sitting calmly at your desk or walking on a nice stable surface. Periodically, the poles switch round it seems but at the moment the magnetic South pole is actually near the point we’d normally call the geographical North pole. They’re pretty close, but the geographic axis doesn’t exactly coincide along the geographic axis of rotation of Earth. And the lines of force go from magnetic North to magnetic South so your compass needle is actually pointing towards magnetic South. Remember iron filings and bar magnets from physics class?

Earth is a big magnet.

The piston is an amazingly simple, ridiculously useful and successful mechanism that, together with a connecting rod and crankshaft, converts linear motion to rotational motion.

This simple system is basically what allows us to take a force produced by, say, steam or an explosion and make a wheel turn. Stick a few of these together and time the rotation of each correctly, carefully controlling the explosions and the exhaust, and you have an internal combustion engine that powers and moves our cars.

There are a lot of amazing things to me about it, but I am still impressed with how effectively it takes something moving back and forth and makes something spin around and vice versa.

The piston

A way of helping decide what to do next based on Must do, Should do, Could do and Would do.

Strangely, so many of the things you’d really like to do when put in this organisation end up in the Would bucket.

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MOSCOW Prioritisation.