the Prism HG and EI.


_PROP._ IX. PROB. IV.

_By the discovered Properties of Light to explain the Colours of the
Rain-bow._

[Illustration: FIG. 14.]

This Bow never appears, but where it rains in the Sun-shine, and may be
made artificially by spouting up Water which may break aloft, and
scatter into Drops, and fall down like Rain. For the Sun shining upon