OF THE PYRAMIDAL SHADOW.

The pyramidal shadow produced by a columnar body will be narrower
than the body itself in proportion as the simple derived shadow is
intersected farther from the body which casts it.

[Footnote 166: Compare the first diagram to No. 161. If we here
conceive of the outlines of the pyramid of shadow on the ground as
prolonged beyond its apex this gives rise to a second pyramid; this
is what is spoken of at the beginning of No. 166.]