Water of Leith.

In my schooldays, I wasn't very good at geography though, I might fare a little better in the modern environment. The subject was split into two parts; the "how and why things happened" and the "what happened where." Remembering that one country produced a particular type of commodity didn't suit my brain but, remembering why that commodity might be produced in a particular type of region was another matter.

I do remember it being explained that there was no river in Britain had not been modified by Man's hand although it was implied that the said Man knew better than Nature and the environment was better for it; but those were the days when continental drift was considered a ludicrous concept. For the sake of preserving these buildings that back onto the water, the stone barricade has been built to prevent the erosion of the bank; however, it upsets the balance of both the flow and the ecology. As rivers run they remove, and deposit, material along the banks, and replacing the bank with a wall affects this balance and the types of flora and fauna that grow there; it also looks bloody awful to my eyes.

A few miles nearer to home, the River Esk flows through Penicuik and numerous villages out to the sea at Musselburgh. A hundred years ago this stretch of water was home to a dozen paper mills, each one powered by a water wheel. The weirs that provided the necessary head of water, and therefore the power to drive the machinery, are still there and some environmentalists wish to use them to create electricity. However, it seems that those in the know wish to remove them and restore the river to its natural state. The weirs both prevent the flow of material downstream (each one is backed up with many tonnes of silt) and stops fauna migrating upstream; animal life can become pretty sparse as you move up such a river. Some invasive creatures benefit considerably from this, the signal crayfish for one; a local expert has suggested to me that their numbers would be seriously moderated if the weirs went.