The beauty of the earth

"Look at that heap of dirt I turned over - mud, clay, stones, and other muck. It's not the most beautiful thing to be discussing over coffee, but it got me thinking. The garden's a sludgy mess, after all the rain we've had, but there's history in there. Yes, I will have a biscuit."

"Thanks. It's much nicer today, isn't it? Just right for sitting outside. Now what was I saying? Oh yes, that pile of earth. There's lots of colours in there. Not strong colours like the plants and flowers, but greys, browns and yellows, plus that darker stuff - I wonder where that came from? It's not like the rest of the garden, so I reckon someone put it in to improve the soil. Maybe it's just peat from the Garden Centre, but even that sets you thinking… We might have a bit of Ireland in this garden. Isn't that interesting? Hang on a minute while I move my chair into the shade."

"Mm, that's better, the Sun was getting too hot there. As I was saying, that soil holds the story of our planet. See those little stones? The way they're rounded off they must have been in a river at some time. There's no river up here, so either they were brought in artificially or they were brought here by a flood. Or maybe that brook down the road changed its course. As for that clay, it's most likely to have been brought down by glaciers and arrived here in the run-off where the glacier ended. It ground the pieces very small; then the water sifted out the smallest particles and carried them to places that were beyond the reach of the moving ice. Like here. It's not very nice when you just look at it as clay - hard as rock last July and all slimy after last week's rain - but imagine the scene when this area was an alpine valley."

"These bigger stones tell a very different story. I was talking to someone the other day about the flat, flaky lumps we keep finding and they say it's not builders' rubbish. It's the limestone bedrock all over this district and would have been laid down in a shallow sea when the area had a tropical climate. I think that means it wasn't the same part of the globe at that time. It's something to do with plate tectonics - that's the bit about the surface of the earth floating around on the molten rock below. You know - the stuff that comes out of volcanoes. The continents shift and change so that an area like this might be thousands of miles from where it was say, 100 million years ago. This place could have been near the equator. There's something to think about in the winter! This might have been a tropical sea with millions of tiny creatures whose shells would fall to the bottom to make this limestone. We're in the tropics!"

"What crawly things? Oh those. Of course I can find something nice to say about them. Yes, and I will get on with the work just as soon as I've finished my coffee. What I'm saying is, even those things we don't like… they've all got millions of years of history behind them and they fit perfectly in their place in the world. If those worms and earwigs weren't there - not to speak of the microscopic bugs we can't even see - if they weren't there our soil would be dead and useless and the flowers wouldn't grow." "OK, I take the point. I've been lounging here for ten minutes lecturing you about a pile of dirt. But it makes you think. Doesn't it?".