h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

That's not just oak. I can quote you tables and tables of figures for different kinds of wood Charcoal is a good insulator.

i only knew about oak because kevin Mcloud said about it in one of his grand designs where they were using green oak as the frame and all the beams were exposed, and he said it didnt need fire retardation treatment un like some other timber due to its propperties, charing and all that

Downward pressure

>they keep the walls on the foundations????<

That's good enough. I'll call that correct +3

I'll explain fully in a few minutes.

The real problem is chestnut. It cracks a lot when it dries out.

As I said at the start, it's just a simple question and answer, so not a lot to explain.

Church roofs are heavy, and so they push outwards on the walls, making the walls likely to fall over. There are several ways of counteracting this, all of which are used to a greater or lesser degree.

You can move the point of stress lower down the wall. The classic hammer-beam roof does this.

You can build thicker walls. Obviously this uses more stone, and can look ugly.

Buttresses and flying buttresses. These push back in the opposite direction to the roof, and can look quite marvellous.

But pinnacles can also play a part.

A vertical free standing wall has lines of thrust directed vertically downwards, caused by the weight of the stone. If you lean a roof against, this adds an oblique component to the lines of thrust. If the combined thrust strays too close to the outer edge of the wall, then the wall may fall over. Stone is very strong under compression, so you can load weight on it without much danger of crushing. Putting a big hefty row of pinnacles on top of the wall increases the vertical thrust, and so proportionately reduces the oblique thrust.

The reason why I find this interesting is the counter-intuitive thing: 'What are those pinnacles for?' 'They stop the church falling down.'

Malabarista DGI +1 - weight

Taff QI +6 - properties of oak beams
Taff correct +3

where are my s

i demand the finest s known to humanity!!!!



don't get me started on the jukebox

Sorry Taff. I thought, with it being a short QI, that there wouldn't be any room for klaxons. Not having them does remove a bit of the fun doesn't it?

Taff, whatever you do, promise me you'll never work in demining. You'd be good at finding them, yes, but only briefly...

Scores submitted 11/02/10

Thanks all.

i have already been rejected for bomb disposal 21 years ago