This is the second of Fred’s Philosphicals, his Think Pieces, which was unfinished when he died.
Why is the Wind? This is the subject of my second Think Piece, and I must admit it is the one that intrigues me most. Mummy is quite correct to identify the Wind Experiments as one of Princeling Fred’s Great Works.
By observation, we can feel that the wind is a movement of air. Exactly what air is I am not going to explore further but state that I am considering it to be a thin fluid, like water but much much thinner, so we can see through it and can’t actually see it unless there are clouds travelling in it. In fact the clouds could be considered to be a bit like pond weed or muddy water travelling in a river. I am lucky enough to live by a river, so I have used the technical process of Analogy and applied it to my Wind Thinking.
Now a river flows in one direction, constrained by its banks. But a couple of times in my lifetime it has jumped out of its banks and spread to the land around. So it can be said about the wind that most of the time it flows in certain directions and takes paths round obstacles in its way like the river does round fallen trees and so on. But the wind, being thinner, gets to go through trees and just move the branches and leaves with its passing. When it is a very fierce wind then it shakes the branches a lot and sometimes it breaks them off. It’s like shaking a piece of hay very fast, if you shake it fast enough it breaks instead of bending. Try it sometime. It’ll make you dizzy though.
The trouble with understanding the wind is that it doesn’t flow in one direction the whole time. Sometimes in flows (or blows) in a completely opposite direction, or at a different angle. After George had told me about the Earth being a ball, we discussed what would happen if the ball was spinning. What would happen to all the loose things on top of it. We thought that most things that are stuck fast to it would be fine, and heavy things relative to water would be ok but could jump up and down (like we do) but things that were fluid would move in a funny way, with a sort of time lag. I’ll talk more about this when I talk about The Sea, as George and I have some very interesting theories which we haven’t been able to test.
But if the Earth is a spinning ball, then the air on top of the surface isn’t attached and it sort of slips over the surface. If the ball was smooth it would just slip round, but all the islands and hills and houses and trees get in the way of it slipping smoothly so it goes into all sorts of whorls, like Victor’s coat. They all make sense when you put them together but from a distance they look completely haphazard. So if the wind turns round in small circles as it slips over the surface of the earth, so it changes direction over the course of a few days depending where this little whorl is over our heads. (Depth of the whorl – speed of the wind – gusts).
That is all Fred wrote, although I’m sure he was going to add some discussion on his wind experiments where he was trying to map how the wind moved round obstructions like the house or the vegetable patches or the garden fence.