- [Narrator:] The spiral pattern around the trunk of the tree... resembles the shape of a screw... the kind of screw used for drawing water uphill.

Silent, and able to keep a constant amount of water flowing against gravity, it would have been an engineering breakthrough.

Sennacherib was using the shape of a date palm to describe an Archimedes screw.

- When you invent something, you've got to find words for it.

Like on your computer, you have this ‘mouse.

Well, you know, that could be quite perplexing in the future for people who talk about mice on desks.

Here, we've got something that maybe they've already invented, and they know what it looks like, but how are they going to find a word for it?

They look in nature for something that has it, too, and this is what provides them with a word that they can use for it, that everybody will understand.

- [Narrator:] The Archimedes screw is named after the Greek who is beleived to have invented it.

But it seems Sennacherib was using it 400 years before Archimedes was even born.

- I looked at what various writers had said about Archimedes and the water-raising screw, and they thought the screw itself was older than Archimedes.

So I felt some relief at that [laughs] because you don't want to go out too much on a limb.

Sennacherib solved this enormous problem of raising water from that aqueduct halfway up the garden and getting it right up to the top above the pillared walkway.

And he does it with these screws.

And that is a stroke of genius, really.