The next map is an azimuthal map projection with all places shown at their correct direction from Seattle. But the map scale is in parcel postage cents.
Look at the radial distance function in the lower right hand corner. The X-axis is the spherical distance from Seattle, the Y-axis is the cost in dollars to send a one pound package within the United States as a function of distance. The graph shows a step function and this collapses much of space. Compare with the method of producing azimuthal projections on a later slide.