The Dew-drop is familiar to every one from earliest infancy. Resting
in luminous beads on the down of leaves, or pendent from the finest
blades of grass, or threaded upon the floating lines of the gossamer,
its “orient pearl” varies in size from the diameter of a small pea to
the most minute atom that can be imagined to exist. Each of these, like
the rain-drops, has the properties of reflecting and refracting light;
hence, from so many minute prisms, the unfolded rays of the sun are
sent up to the eye in colours of brilliancy similar to those of the
rainbow. When the sunbeams traverse horizontally a very thickly-bedewed
grass-plot, these colours arrange themselves so as to form an iris,
or dew-bow; and if we select any one of these drops for observation,
and steadily regard it while we gradually change our position, we
shall find the prismatic colours follow each other in their regular
order.--_Wells._