But he was not doing so because it was a hyperbola, or (to look at it another way) it was not a hyperbola because he was doing so. This was simply the route that traders had always taken, going from market to market as they traveled up out of Ipswich with wagon-loads of imported or smuggled goods. He could have followed a zigzag course. That it looked like a hyperbola when plotted on a map of England was luck. It was a contingent truth.