Biology
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Plants free oxygen from carbon dioxide when the sun shines, and release carbon dioxide at night. Sometimes, you can see it happen. I was eating lunch down by the water on Friday. We've had a couple of calm, very sunny days when the temperature has reached the lower 20's (C). But the lake is still very cold, and because of that pretty clear--you can see the bottom to depths of six feet or more (that passes for "clear" here, whereas where I grew up it would pass for "opaque".) The shells of last year's zebra mussels still thickly carpet the rocks at depths of more than a few feet. Near the shore, where it's shallower, I think the ice must have cleaned them off over the winter, leaving almost bare rock that's liberally inhabited by some kind of green weed that looks a bit like sea-lettuce. I noticed all this, and then noticed that the rocks also seemed to be covered with air bubbles, shining like prolate diamonds in the sun. They were anywhere up to a 3/8 of an inch in size, and when I clambered down and put my nose to the surface to get a better view I realized they were all wrapped around the smaller plants. The taller plants sometimes had one or two bubbles caught in their foliage, but even as I watched I saw several get knocked loose as the plants wavered under the influence of the growing waves. The place I was sitting is inside a sea-wall, so the waves were tiny even though the wind was coming up, but it was still enough to start a cascade of bubbles that eventually reached even the smaller plants. After a little bit of research I'm pretty sure they are a mixture of C02 and oxygen, but no longer sure what the proportions are. Solubility of gases depends on temperature and acidity in a complicated way, and chemist's penchant for strange units makes it hard for normal people to figure out what they mean (for instance, what does a solubility in ml/ml mean? ml of gas at STP? If so, why?) But whatever the gas is, it had clearly built up over the previous few days of clear, bright, very calm weather, a positive sign that the engine of springtime is running smoothly and well after a long winter in moth-balls.
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in thread: caro2001_05_06:11:26
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The flower in the picture is Caro's hybrid fuschia that she has named Winston Churchill, something that, as a great admirer of Churchill, just cracks me up. "Tyrian hue" means "purple", the color of royalty. In ancient Greece and Rome it came from Tyre, and was made from some kind of mollusk. In Imperial Rome only the emperor was allowed to wear purple--it was considered treason for anyone else to do so, and punishable by death. Now, some people like purple, but in circumstances like those the only people who dared to do it had to like purple a lot, with an almost psychotic passion, and even they only dared to it in private. And the meaning of wearing purple was distorted. It no longer just meant, "I like purple." It meant, "Purple means power, and I love power so much that I'm willing to risk my life to emulate the most powerful person in the world." Wearing purple became a fetish.
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