On Thu, 13 Nov 2003 08:35:40 +0000, Jon wrote:

Hi!

Does anyone know what this thing is? It looks like a giant wooden corkscrew
and is inside the Ribat in Sousse, Tunisia.

http://herrhagen.net/pictures/sousse2/02.html

It looks like something to help lift heavy objects with or some torture
equipment... Does anyone know for sure?

While traveling in Tunisia, didn't you notice a few (millions) olive trees
on the countryside ?

This piece of wood is part of the hand press from an olive oil mill. The
large beam is embedded in an alcove with the screw going vertically
through it. The screw is used to guide the part that actually presses the
olives that have been previously milled. The resulting oil needs some
filtering and it is then fit for consumption.

This design is in use in many places around the Mediterranean.

For more details :
http://lorgues.free.fr/moulins11.html
http://www.provenceweb.fr/83/centre-var/moulins/doc.htm

The explanations are in French, but the pictures should be explanation
enough.