Mummius looked suddenly seasick. 'I never said-'

'Indeed you did not. You're a good soldier, Marcus Mummius, and you divulged nothing to me that you were sworn to conceal. Still, I'm curious to know when we'll come to Baiae.'

'What makes you think-'

'I think, Marcus Mummius; exactly. I would hardly be the man your employer was seeking if I couldn't figure out a simple riddle such as our destination. First, we are most assuredly heading south; I'm not much of a sailor, but I do know the sun rises in the east and sets in the west, and since the afternoon sun is on our right and the coast on our left, I deduce we must be sailing south. Given the fact that you promise that my work will be done in five days, we can hardly be going beyond Italy. Where else, then, but a town on the southern coast, and most likely on the Cup? Oh, perhaps I'm wrong in choosing Baiae; it could be Puteoli, or Neapolis or even Pompeii, but I think not. Anyone as wealthy as your employer – able to pay five times my fee without a qualm, able to send a ship such as this on what seems to be a whim – anyone that rich is going to have a house at Baiae, because Baiae is where any Roman who can afford it builds a summer villa. Besides, yesterday you said something about the Jaws of Hades.'

'I never-'

'Yes, you said many lives were at stake, and you spoke of babies wailing in the Jaws of Hades. Now, you could have been speaking in metaphors, like a poet, but I suspect there is a conspicuous absence of poetry in your soul, Marcus Mummius. You carry a sword, not a lyre, and when you said "Jaws of Hades" you meant the words literally. I've never seen it for myself, but the Greek colonists who originally settled around the Cup believed they had located an entrance to the underworld in a sulphurous crater called Lake Avemus – also known as the Jaws of Hades, Hades being the Greeks' word for the underworld, which old-fashioned Romans still call Orcus. The place is only a brisk walk, I hear, from the finest homes in Baiae.'