What is it?

A little quiz for you today. What do you think this is?

A few helpful hints. 'A piece of tree' won't do - this is a part of a piece of early technology. But what was it used for? And how? To give some scale, it's about 30 cm across.

And the answer is...

... it's a piece of a wooden water main. I saw it on a visit to WRC in Swindon with Radio Wiltshire presenter Mark O'Donnell (the recordings of our visit will be broadcasting on his Sunday morning show, probably starting next Sunday). The company provides services to the water companies and have interesting facilities, including an indoor section of road as a test pit where pipes are buried and then put under pressure to see how and when they fail.

Remarkably, the WRC chief exec informed us that, in all probability, there are still some wooden water pipes in use in the UK. Another surprise was to discover that a fair number of older houses still get their drinking water through lead pipes. The water companies use a dilute phosphoric acid to coat the pipes on the inside so that lead doesn't get into the drinking water.