THE RAINBOW. 
251 
of the rainbow, as a key to the mysteries of man^s rela¬ 
tions to the Divine essence ? We know not, but it is a 
key for all that; and herein we see how the discoveries 
of science lend help to theology, and indicate truths that 
lie at the foundation of all harmonies, both of matter 
and of spirit. 
Consider what a wonderful work a rainbow is. The 
passage of light through a refracting medium causes the 
light to separate into its component parts. We see those 
component parts as it were in the colours of the arc. 
Ordinary daylight is a compound of all colours, say, to 
use a homely phrase, all the colours of the rainbow. 
The use of a prism is to anatomize a ray of light, and 
cause it to exhibit the violet, green, amber, orange, and 
red rays of which it is composed. Just as the prism 
dissects all rays of light, so does each drop of water of 
which the rainbow is composed; but those are fattiny 
drops; if they were suspended and immoveable, we might 
more easily understand the history of the phenomenon. 
All the colours we behold in the rainbow are around 
and about us in the daylight, so diffused and blended, 
that we can know nothing of their separate powers, until 
by some act of refraction each is made manifest. But 
each colour has its own peculiarity, so persistent that 
they may all be obtained from a pencil of light not 
thicker than a cobweb, as easily as from a broad band of 
uninterrupted sunlight. In a dark room, admitting 
light only by a small hole pierced in a shutter, the prism 
may be so positioned as that the place of the red, the 
orange, or the violet ray shall be determined beforehand ; 
for each ray comes out at its own angle, and the places 
