‘But why bury a sun-powered device thirty feet underground? We’ve examined dozens of theories, though we realise that it may be completely impossible to understand the motives of creatures three million years in advance of us. ‘The favourite theory is the simplest, and the most logical. It is also the most disturbing. ‘You hide a sun-powered device in darkness - only if you want to know when it is brought out into the light. In other words, the monolith may be some kind of alarm. And we have triggered it . . .
