CONCENTRIC RAINBOWS.
This extraordinary phenomenon, which is seen at sunrise on the Andes, in South America, was first witnessed by Ulloa and his companions in the wild heaths of Pambamarca, and is thus described by him. “At day-break the whole of the mountain was enveloped in dense clouds, which at sunrise were dissipated, leaving behind them vapors of so extreme a tenuity, as not to be distinguishable to the sight. At the side opposite to that where the sun rose on the mountain, and at the distance of about sixty yards from the spot where we were standing, the image of each of us was seen represented as if in a mirror, and three concentric rainbows, the last or most exterior colors of one of which touched the first of the following one, were centered on each head. Without the whole of them, and at an inconsiderable distance, was seen a fourth arc purely white. They were all perpendicular to the horizon; and in proportion as any one of us moved from one side to the other, he was accompanied by the phenomenon, which preserved the same order and disposition. What was, however, most remarkable, was this, that although six or seven persons were thus standing close together, each of us saw the phenomenon as it regarded himself, but did not perceive it in the others. This, adds Bouguer, is a kind of apotheosis, in which each of the spectators, seeing his head adorned with a glory formed of three or four concentric crowns of a very vivid color, each of them presenting varieties similar to those of the first rainbow, tranquilly enjoys the sensible pleasure of reflecting that the brilliant garland he can not discover in the others is destined for himself alone.”
A similar phenomenon is described by Mr. Hagarth, as having been seen by him in Wales, on the thirteenth of February, 1780. His relation is as follows. “In ascending, at Rhealt, the mountain which forms the eastern boundary of the vale of Clwyd, (in Denbighshire,) I observed a rare and curious phenomenon. In the road above me, I was struck with the peculiar appearance of a very white, shining cloud, which lay remarkably close to the ground. The sun was near setting, but shone extremely bright: I walked up to the cloud, and my shadow was projected into it, its superior part being surrounded, at some distance, by a circle of various colors, whose center appeared to be near the situation of the eye, and whose circumference extended to the shoulders. This circle was complete, except what the shadow of my body intercepted. It exhibited the most vivid colors, the red being outermost; and all of them appearing in the same order and proportion as they are presented to the view by the rainbow. It resembled very exactly what in pictures is termed a glory, surrounding the heads of saints; not indeed that it exhibited the luminous radiance that is painted close to the head, but an arch of concentric colors placed separately and distinctly from it. As I walked forward, this glory approached or retired, just as the inequality of the ground shortened or lengthened my shadow. The cloud being sometimes in a small valley below me, sometimes on the same level, or on higher ground, the variation of the shadow and glory became extremely striking and singular. To add to the beauty of the scene, there appeared, at a considerable distance to the right and left, the arches of a white, shining bow. These arches were in the form of, and broader than a rainbow; but were not completely joined into a semicircle above, on account of the shallowness of the cloud.”