« PreviousContinue »
but left to decay on the spot. In Rome they were held sacred; but Numa enacted that all persons killed by lightning should be interred immediately, without any funeral ceremony. During a thunder
of New-Holland rush out of their huts and deprecate its vengeance. The Gentoos believe that thunder and lightning proceed from an evil spirit, whose supreme delight consists in counteracting the benevolent plans of Providence. When it thunders, therefore, they vent virulent curses against him.
Thunder, lightning, rain, and winds are constantly employed by the poets to illustrate their subjects. Thus Southey, in his poem of Madoc:
'Tis pleasant by the cheerful hearth to hear
Woo terror to delight us.
Behold where Dryden's less presumptuous car
If we hold green glass to the eye, every object seen through it appears green : hence it may be supposed, that to those insects which have green, blue, or indigo eyes, everything they see appears of a green, blue, or indigo colour. Labrador seldspar exhibits a brilliant display of colours ; but, as with the opal, they all depend on the position in which the stone is held to the light. Gems, on the other hand, derive their hues from the metals with which they are impregnated.
The tintings of the clouds are caused by the refrangibility of the sun's rays. These visions, these mimic representations-designed, as it were, by the Eternal, in mockery of man's works and as emblems of their instability-charm alike the philosophic eye, prying into the secrets of Nature, and the heart of The peasant, who at a greater distance admires her beauties and yields to her influences. Gaze, too, my Lelius, on the fine-formed arch of the rainbow, and be enraptured with its splendour as it encircles the horizon on the extended plain, or hangs from the side of the lofty mountain.
I do not remember that it has been expressly noticed by our philosophical writers, but it is nevertheless evident that the ancients had a knowledge of the rainbow's being formed by the refraction of the sunbeams and the falling of rain. We may infer this from the allegory of the winds in the Iliad ; from what Ælian says of Pythagoras; from a passage in the fifth Eneid,* and another in the sixth book of Lucretius.fi
Nothing can be more express than the language of Pliny : “ Quod ergo iris sit refractio aspectus est ad solem, manifestum est." And as Plutarch declares it to have been a circumstance well known in his time, it is difficult to conceive why, in the present, Antonio de Dominist should be honoured as a discoverer
Ceu nubibus arcus
Lib. v., l. 88.
Lib. xii., ep. xxix., 6. Huic, ubi sol radiis, &c,
De Rer. Natur., vi., 523. I In his " De Radiis Visus et Lucis," wherein he improved upon a hint given by Vitello, in a treatise published in the Thesau. rather than a reviver of a truth which Descartes more fully explained,* and which Newton completely illustrated by analyzing the properties of colour.
The poets feigned the rainbow to be the abode of certain aërial creatures, whose delight it is to wanton in the clouds; and Milton, in his exquisite pastoral drama, thus alludes to this fanciful idea :
I took it for a fairy vision
And play in th' plighted clouds. The rainbow, which not improbably first suggested the idea of arches, though beautiful in all countries, is more particularly so in mountainous ones; for, independent of its greater frequency, it is impossible to conceive an arch more grand, if we except the double ring of Saturn, than when its extreme points rest upon the opposite sides of a wide valley, or on the peaked summits of precipitate mountains.
One of the glories which are said to surround the throne of Heaven is a rainbow like an emerald. In the Apocalypse it is described as encircling the head of an angel; in Ezekiel, four cherubim are compared to a cloud arched with it; and nothing out of the Hebrew Scriptures can exceed the beauty of that passage in Milton, where he describes its creation and first appearance. There is a picture representing this emblem of mercy, so admirably painted, in the castle of Ambras, in the circle of Austria, that the Grand-duke of Tuscany offered a hundred thousand crowns for it. Rubens frequently gave animation to pictures which had little besides to interest the eye of the spectator, by painting this
rus Opticæ, 1572, in which he says “that refraction as well as reflection do produce a rainbow."
* Descartes showed that the first bow is formed by one reflection and two refractions; and the second by the suns rays' falling upon drops of rain, and emerging after two refractions and two reflections.
phenomenon: one of Guido's best pieces represents The Virgin and Infant sitting on a rainbow; and round the niche in which stood a statue of the Virgin in the chapel of Loretto, were imbedded precious stones of various lustres, representing the hues of the rainbow.
The rainbows of Greenland are frequently of a pale white, fringed with brownish yellow, arising from the rays of the sun being reflected from the frosty vapours in the air. In Iceland it is called the “Bridge of the Gods," and the Scandinavians gave it for a guardian a being which they called Heimdallar: they supposed it to connect heaven with earth.
Ulloa and Bouguer describe circular rainbows,* which are frequently seen on the mountains rising above Quito, in Peru; while Edwards asserts that a rainbow was seen near London, caused by the exhalations of that city, after the sun had set more than twenty minutes. A naval friend informs me that as he was one day watching the sun's effect upon the exhalations near Juan Fernandez, he saw upward of five-and-twenty ires marina animate the sea at the same time. In these marine bows, the concave sides were turned upward, the drops of water rising from below, and not falling from above, as in the aërial arches. They are sometimes formed by waves, also, dashing against the rocks.
In some rainbows may be discovered three arches within the purple of the common bow: 1. yellowish green, darker green, purple ; 2. green, purple ; 3. green, purple. Rainbows are sometimes seen, also, when the hoar-frost is descending; and Captain Parry, in his attempt to reach the North Pole by boats and sledges, saw a fog-bow, and no less than
* When M. Labillardière was on Mount Teneriffe, he saw his body traced on the clouds beneath him in all the colours of the solar bow. He had previously witnessed this phenon on the Kesrouan, in Asia Minor.-D'Entrecasteaux's Voy. in Search of La Pérouse, vol. i., p. 18, 19.
five other complete arches formed within the main one, all beautifully coloured.
Often have I stopped, even in the streets of London, to gaze on haloes of the moon. Haloes are much more rare in northern countries than in southern. Humboldt relates, that in the torrid zone they appear almost every night. They are seen, also, round the planet Venus, the purple, the orange, and the violet being distinctly perceived ; none are observed, however, round Sirius, Canopus, or any other of the fixed stars. Dr. Halley saw at Oxford a beautiful halo round the moon, within the circumference of which were Saturn, the Pleiades, Capella, and the foot of Perseus.
A.ristotle asserts that he was the first who ever noticed a lunar rainbow. He must mean that he was the first who ever described one, since lunar rainbows must have been observed in all ages. That it was unknown to St. Ambrose, however, is evident from his belief that the bow, which God promised Noah he would place in the firmament after the Deluge, “as a witness that he would never drown the world again," was not the rainbow, “which," says he, “can never appear in the night, but some visible virtue of the Deity." Notwithstanding the incredulity of St. Ambrose, however, I have had the good fortune to see several myself, two of which were perhaps as fine as could be witnessed in any country. The first formed an arch over the Vale of Usk. The moon hung over the Blorenge; a dark cloud was suspended over Myarth, and a bow, illumined by the moon, stretched from one side of the vale to the other. The second I saw from the castle overlooking the Bay of Carmarthen, forming a regular semicircle over the Towy.