Many remarkable phenomena attend this state of the atmosphere, known as the Fata Morgana of Sicily, the Mirage of the Desert, the Spectre of the Brocken, and the more common exhibitions of halos, coronæ, and mock suns. The Mountain House at Catskill has repeatedly been seen brightly pictured on the clouds below. Rainbows are also due to this condition of the atmosphere.
We might occupy the remainder of the space allowed us by enlarging on various topics which belong to this part of our subject. The twilight gray, the hues of the evening and morning sky, the peculiarity of the red rays of light, the scintillation of stars, their flashing changes of colors, are all meteorological in their character, as well as strikingly beautiful and interesting.
Polarity of light is another of the wonders of which Meteorology takes cognizance. The celebrated Malus, in 1808, while looking at the light of the setting sun shining upon the windows of the Luxembourg, was led to the discovery that a beam of light which was reflected at a certain angle from transparent and opaque bodies, or by transmission through several plates of uncrystallized bodies, or of bodies crystallized and possessing the property of double refraction, changed its character, so as to have sides, to revolve around poles peculiar to itself, and to be incapable of a second reflection. The angle of polarity was found to be 54°.
The beam of polarized light was also found to have the peculiar property of penetrating into the molecules of bodies, illuminating them and, enabling the eye to determine as to their structure. The production of beautiful spectres, prismatic colors of gorgeous hues, and the most remarkable system of rings, has followed the discovery, and important results are expected from the continuation of the researches. It has already enabled the astronomer to determine what heavenly bodies do or do not shine with their own light. The subject is still under investigation.
Color from light comes also under the notice of the meteorologist. The received opinion is, that there is no inherent color in any object we look at, but that it is in the light itself which falls upon and is reflected from the object. Each object, having a particular reflecting surface of its own, throws back light at its own angle, absorbing some rays and dispersing others, while it preserves its own. In this sense it may be said that the rose has no color,--its hues are only borrowed. If the idea should be carried out, it would certainly destroy much of the poetry of color. Thus, in praising the modest blush which crimsons the cheek of beauty, we should destroy all its charm, if we attributed it to a sudden change in the reflecting surface of the epidermis,--a mere mechanical rushing of blood to the skin, and a corresponding change in its angle of reflection!