There were tolls everywhere, but no center of power. The cattle-herds spread out away from the high road and into pastures flat as ponds, leaving them and the strewn parades of Hollandgänger to traipse along for a day or two, until they began joining up with other, much greater roads from the south and east: nearly unbroken queues of carts laden with goods, fighting upstream against as heavy traffic coming from the north. 'Why not just stop and trade in the middle of the road?' Jack asked, partly because he knew it would provoke Eliza. But she wasn't provoked at all – she seemed to think it was a good question, such as the philosophical Doctor might've asked. 'Why indeed? There must be a reason. In commerce there is a reason for everything. That's why I like it.'