, count up the number, and report the result as the earth’s distance from the sun. The measuring rods, you will remember, adjust their lengths proportionately to the radius of curvature of the world. The curvature along this contour is rather large and the radius of curvature small. The rods therefore are small, and there will be more of them in
than the picture would lead you to expect. If the earth chooses to go to
the curvature is less sharp; the greater radius of curvature implies greater length of the rods. The number needed to stretch from
to
will not be so great as the diagram at first suggests; it will not be increased in anything like the proportion of
