According to Professor Giovanni Pettinato of the University of Rome, a rock crystal lens, currently on show in the British museum, could rewrite the history of science. He believes that it could explain why the ancient Assyrians knew so much about astronomy. It is a theory many scientists might be prepared to accept, but the idea that the rock crystal was part of a telescope is something else. To get from a lens to a telescope, they say, is an enormous leap. Professor Pettinato counters by asking for an explanation of how the ancient Assyrians regarded the planet Saturn as...