And Scott has told us of the belief in Scotland and the northern isles, of spirits abroad in the upper air:
“The monk gazed long on the lovely moon,
Then into the night he looked forth:
And red and bright, the streamers light,
Were dancing in the glowing north.
So had he seen, in fair Castile,
The youth in glittering squadrons start,
Sudden the flying jennet wheel,
And hurl the unexpected dart.
He knew by the streams that shot so bright,
That spirits were riding the Northern light.”
The light emitted by the aurora varies much in intensity. Ordinarily it is not greater than that of the moon in her first quarter; but a few instances are recorded where it was powerful enough to make itself perceptible by day; and on one occasion it was strong enough at night to cast a shadow in the midst of a Newfoundland fog. As the phenomenon has been carefully studied only within a century, it is not safe to affirm with certainty what records of the past three hundred years have induced many to believe; that it is of special frequency at periods of one hundred and fifty years. This can only apply to the temperate zones; for in the polar world it is to be seen on almost every clear still night.
M. Martins has given us a striking picture of the auroras. “At times they are simple diffused gleams or luminous patches; at others, quivering rays of pure white which run across the sky, starting from the horizon as if an invisible pencil were being drawn over the celestial vault. At times it stops in its course: the incomplete rays
LAND OF THE AURORA.