Hi everyone and welcome to stone shifting 2. It's true, I do have two brains! One is under my desk and runs at 2.4GHz, the other is in my skull and works at a tiny fraction of that speed, but is reasonably adept at telling the first one what to do.

Anyway, just to prove that I am fallable, I think I got the explanation wrong for the side forces on the Tower. Here is the revised version: The frictional force (which acts along the surface of the block) and the reaction force of the tower (which acts perpendicularly to the block) resolve to a vertical component that exactly balances with the weight of the block, so there is no side load. However, when the block begins to slip, the frictional force is no longer sufficient to balance the reaction force and the weight. This results in a net side load being imposed on the tower.

To verify this theory, I placed a long wooden lath on top of a tall, narrow support block so that it would just overbalance. As the lath rotated the support block remained upright until the point of slipping was reached. It then imediately fell over.

I'm happy with this new explanation for two reasons. Firstly, the side forces should be a lot less than I had feared and secondly, I couldn't get the maths to work properly before, but now it all falls into place quite nicely.

Just some thoughts on the legs of the "A" frame getting stuck at the critical moment. I have always envised the legs of the "A" frame being placed in a sort of a timber trough (Greased) so that as the rope burns through the legs slide away freely. To work properly the "A" frame must be perfectly plumb, then the whole thing collapses out of the way.

"There’s a hope for involvement by a film company and/or academics (anyone have any futher ideas or contacts?)"

I could get something through to Aubrey Burl. Would he do?

Have a project title, yes good idea, but which project? Doesn’t it naturally fall into 2 parts, and hasn’t Gordon had two separate ideas? It seems to me that we could first of all make a big deal out of part one, transporting a single standing stone and pivoting it into place. It would be enough to make a big impact in terms of commercial interest and archaeological cred, and might give us a better springboard and support in both respects for going on to the big one.
The idea of “Stone-walking” is such a great one that I’d like it to have it’s own starring role first rather than being eclipsed by the Trilithon thing. Any element of failure in the latter (dare I say there’s at least a possibility of that?) would be a shame in itself but it would be an even bigger tragedy if the stone-walking brainwave was discredited because it was linked with photos of a wonky trilithon…

Yes, Gordon, I know it won’t happen, but I’d just like to know that you’re looked up to by the establishment before you even try. The thing is, part one is pretty much a practise for the big event so you’re going to have to do it anyway, so why not make it a big deal?

Another (tentative, slightly mischievous) thought about the first project: if you’re going to row a stone some distance before erecting it, wouldn’t it be a bit of fun to start the journey by floating it along a local river for a little way? The Bluestone project sounds like a good name. The last attempt to move a bluestone was a bit of a horlicks as you know. Apart from the little matter of sinking it they found dragging it overland was a huge problem. In that respect at least you should be able to demonstrate a far better method. (They had a £100,000 Millennium grant. Wouldn’t it be satisfying for a “humble chippy” to show them how to do it!)

(Should we use descriptive titles for sub threads, as I’m finding it hard to refer back?)

Am I right that Steve’s idea is to have a pivoting log fixed transversely across the underside of the stone, so whilst the stone rotates from horizontal to vertical the pivot log effectively rolls through 45%?

If so, lots of questions occur to me, including some possible dangers to be considered:

It’ll take a bit of computing because, as well as pivoting, the stone is following the curve of the log and moving through a small arc, which it wasn’t before.

I guess physical positioning of the pivot log on the edge of the tower needs to be extremely accurate i.e. the computer model may predict it’ll end up vertical but if it’s physically placed 4% off from the edge of the tower that’ll translate into the stone ending up 4% off vertical, maybe more.

Also, what form is the edge of the tower? Is it square or is it another log? If the latter, can we place the stone pivot log exactly on top of the tower pivot log, along their whole lengths and will the one effectively roll round the other, uniformly?

“I'm still thinking about the reason for the slopeing side, the ancients never did anything without a reason.”
“We must find out the profile of the holes for the Trilithon, whatever the holes say is OK by me.”

I’ve tried, but it’s got me beat. Let’s hope someone on TMA can help. Failing that, if Four Winds managed to get Mr Burl interested we could go on his opinion.
I’d love to think there was a chance that there’s enough evidence to at least indicate a “most likely” method, based particularly on how much room they had.
But what if the evidence and/or Mr Burl suggested “large numbers hauling up” was more likely? Would you want to switch to that? Your method is always going to remain a possibility, so demonstrating it will remain a valid option. So it would come down to your personal preference as to what you wanted to do.

I have been bemused by the way that that this thread has evolved.

You`re busy trying to work out the details of swinging a 40 ton stone, perched on a flimsy platform above the ground, when we haven`t even moved (never mind lifted) such a stone as far as one inch!

Don`t get me wrong, I believe that it *can* be done, but *certainly not* in one day, and with resources that are far beyond our means, at present.

As far as I can see, a 4 ton stone has been moved a short distance on a *prepared surface* and been raised 4 feet onto pallets. We`ll need a hell of a lot more practical experience than that to be able to decide what`s required to shift a 40 ton stone.

I reckon that a flimsy, unsafe tower, 12 feet high, would require a minimum of 72 logs of 1 foot diameter, over one third of which would be about 30 feet long (and that`s assuming that the logs can carry the weight). As for a platform for the `oarsmen`, it seems that we`re going to cheat by hiring some scaffolding.

I`ll try not to mention this again, but you should settle for moving a 40 ton stone over Salisbury Plain, an enormous task, first. If you can do that, you`ll get the funding for tackling the far more difficult and expensive problem of raising a trilithon.

Anyway, the sooner we get a small team together to actually get some practise in shifting stones about, the better.

:o)

baz

Start another bloody thread, Nigel. I've told you before, I won't tell you again. ;) ;)