60	THE YUKON TERRITORY.
much overcast with cirro-stratus clouds, which were rapidly passing in a different direction from the wind at the surface of the earth, which last was from the north. The light before alluded to approached with the wind, at about half the pace of the wind, in a cloudlike shape or condition, not far from the surface of the earth. The form of this luminous cloud was in successive waves, or ripples, and resembled the rings of smoke rising from a pipe, one within another, gradually expanding. The inner or focal rings were more intense than the outer ones, and the light was more intense in some parts of the rings than in others. They advanced as the ripples do when a stone is thrown into still water, and these ripples were compressed in an oval form by the wind, the longer diameter being east and west, across the current. It showed unmistakably that the shining medium was in consistence similar to cloud or mist. From the brighter portions of the rings, light streams of the same medium occasionally dripped, and dissipated at some distance below the point whence they originated ; from which it might be inferred that the more intense portion of this medium was denser than the atmosphere. No rays or streamers issued upwards from the upper edges of the rings, which were clearly defined and below the real clouds, of which the altitude seemed less than fifteen hundred feet. The hills from between which the auroral cloud had issued, and the tops of the higher trees between the fort and the hills, were dimly seen, or obscured by the lower portion of the haze, or cloud, which seemed not more than a hundred feet above the earth, as seen from the roof of the higher building. It followed the air-currents entirely; and all its motions seemed guided or controlled by them. Wavy outlines in the ripples seemed caused by the differing velocity of the air in different parts of the current. It covered the whole sky in about two hours from the time of its first appearance. As it spread and enlarged, the light became fainter. It did not give out a positive light, but had a mildly luminous appearance, like phosphorescence.*
Captain Ketchum and Mike had returned February 1st, bringing with them Captain Everett Smith, of the Wilder, and a
* These remarkable phenomena were observed, in a greater or lesser degree, in several instances, of which an account was communicated to the National Academy, at its session in September, 1869, by the writer.