"Here is what I told the Duke of Marlborough concerning Alchemy," Daniel said, which brought Roger to attention. "It has been my view for some years that a new System of the World is being created around us. I used to suppose that it would drive out and annihilate any older Systems. But things I have seen recently, in the subterranean places beneath the Bank, have convinced me that new Systems never replace old ones, but only surround and encapsulate them, even as, under a microscope, we may see that living within our bodies are animalcules, smaller and simpler than us, and yet thriving even as we thrive. When we have stronger microscopes I should not be surprised to discover yet smaller and simpler organisms within those animalcules. And so I say that Alchemy shall not vanish, as I always hoped. Rather, it shall be encapsulated within the new System of the World, and become a familiar and even comforting presence there, though its name may change and its practitioners speak no more about the Philosopher’s Stone. It shall be gone from view but it shall continue to run along beneath, as the lost river Walbrook streams beneath the Bank of England."