"So it's sloping right to left." The next step is to determine the severity of this slope, on a scale from one to five, with ...

if they are far apart the slope is gentle. Contour lines are usually drawn at 10 metre intervals on a 1:50,000 scale map and at 5 metre intervals on a 1:25,000 scale map.

The result was a curvilinear relationship that, remarkably, was linearized when the data were re-plotted onto a log-log scale (Figure 1). Even more interesting was the fact that the slope of this ...