there are many questions connected
with the nature of the sun which not even the most powerful telescope
would enable us to solve, but which the spectroscope has given us the
means of investigating.

What we receive from the sun is warmth and light. The intensely heated
mass of the sun radiates forth its beams in all directions with
boundless prodigality. Each beam we feel to be warm, and we see to be
brilliantly white, but a more subtle analysis than mere feeling or mere
vision is required. Each sunbeam bears marks of its origin. These marks
are not visible until a special process has been applied, but then the
sunbeam can be made to tell its story, and it will disclose to us much
of the nature of the constitution of the great luminary.

We regard the sun's light as colourless, just as we speak of water as
tasteless, but both of those expressions relate rather to our own
feelings than to anything really characteristic of water or of sunlight.
We regard the sunlight as colourless because it forms, as it were, the
background on which all other colours are depicted. The fact is, that
white is so far from being colourless that it contains every known hue
blended together in certain proportions. The sun's light is really
extremely composite; Nature herself tells us this if we will but give
her the slightest attention. Whence come the beautiful hues with which
we are all familiar? Look at the lovely tints of a garden; the red of
the rose is not in the rose itself. All the rose does is to grasp the
sunbeams which fall upon it, extract from these beams the red which they
contain, and radiate that red light to our eyes. Were there not red rays
conveyed with the other rays in the sunbeam, there could be no red rose
to be seen by sunlight.

The principle here involved has many other applications; a lady will
often say that a dress which looks very well in the daylight does not
answer in the evening. The reason is that the dress is intended to show
certain colours which exist in the sunlight; but these colours are not
contained to the same degree in gaslight, and consequently the dress has
a different hue. The fault is not in the dress, the fault lies in the
gas; and when the electric light is used it sends forth beams more
nearly resembling those from the sun, and the colours of the dress
appear with all their intended beauty.

The most glorious natural indication of the nature of the sunlight is
seen in the rainbow. Here the