ratively recent acquirements. In
the old hymns of the Rigveda the chariot of the sun is described
as glowing with varied colour, and its horses as gold-like or
beaming with sevenfold hues; but although there was a word for
the blue of the sea and for indigo dye, this word is never applied
to the brightness of the sunlit vault. So, still more strangely, we
find that notwithstanding the laughing blue of the Greek sky,
old Homer never calls it blue! He has his rosy-fingered dawn,
the parallel of Tennyson's scarlet shafts; but the daylight sky
seems to have been for him as for Enoch Arden, a "blaze." Nor
is the omission supplied in the later classical literature; and the
older Greek writers on science use such epithets as "air-coloured,"
as substitutes for more specific terms. A German scholar
who has examined the ancient writings of the Chinese claims
for them priority in the recognition of the blue of the sky,
and points out that in the Schi-king, a collection of songs from
about 1709 to 618 B.C., the sky is called the vaulted blue, as in
the more modern language it is called the reigning blue.

Delitzsch, from whom much of what is just stated has been
derived (as also from Gladstone's paper on Homer's colour-sense)
does not find the blue of the sky recognised in Europe earlier
than the oldest Latin poets of the third century B.C., who
use _caerulus_ of the sky, and henceforth this epithet takes its
place in literature, Pagan and Christian. And the appreciation of
the heaven-colour develops apace until we have Wordsworth's
"Witchery of the soft blue sky."

The explanation of this late development is a problem of much
interest from the point of view of the physiologist and the
psychologist, in its bearing on the history of the special senses.
It would not be safe to say that the colour was not perceived, in
a somewhat loose sense of that term, but rather that it was not
consciously distinguished. As with the child, so with primitive
man, the strong sensations are the first to be definitely
apprehended--the glow of flame, the scarlet and crimson of
dawn and sunset, the gold of the sun and moon and stars. Red
and yellow were the first to assert themselves; and the two are
significantly combined in Homer's descriptions of the dawn--the
yellow of the crocus as a garment, and the flush of the rose for
the fingered rays.

We must not imagine, however, that the failure to distinguish
the hues and grades of blue argued any l