ATMOSPHERICAL REFRACTION.

A surprising instance of atmospherical refraction occurred at Hastings,

England, on the twenty-sixth of July, 1798. W. Latham, Esq., sitting in

his dining-room, situated on the parade, close to the sea-shore, and

nearly fronting the south, about five in the afternoon, had his

attention suddenly drawn by a great number of people running down to the

seaside. On inquiring the reason, he was informed that the coast of

France was plainly to be distinguished by the naked eye. On going down

to the shore, he was surprised to find that, even without the assistance

of a telescope, he could very plainly see the cliffs on the opposite

coast; which, at the nearest part, are between forty and fifty miles

distant, and are not to be discerned, from that low situation, by the

aid of the best glasses. They appeared to be only a few miles off, and

seemed to extend for some leagues along the coast. Pursuing his walk

along the shore to the eastward, close to the water’s edge, and

conversing on the subject with the sailors and fishermen, they could

not, at first, be persuaded of the reality of the appearance; but soon

became so thoroughly convinced, by the cliffs gradually appearing more

elevated, and approaching nearer as it were, that they pointed out and

named to him the different places they had been accustomed to visit,

such as, the Bay, the Old Head or Man, the Windmill, &c., at Boulogne;

together with St. Vallery, and other places on the coast of Picardy.

This they afterward confirmed, when they viewed them, thus refracted,

through their telescopes, observing that the above places appeared as

near as if they had been sailing, at a small distance, into the harbors.

From the eastern cliff, which is of a very considerable hight, a most

beautiful scene presented itself to Mr. Latham’s view, for there he

could at once see Dungeness, Dover cliffs, and the French coast, all

along from Calais, Boulogne, &c., to St. Vallery; and, as some of the

fishermen affirmed, as far to the westward even as Dieppe. By the

telescope, the French fishing-boats were plainly to be seen at anchor,

and the different colors of the land on the hights, with the buildings,

were perfectly discernible. This curious phenomenon continued in the

highest splendor till half past eight o’clock, notwithstanding a black

cloud for some time totally obscured the face of the sun, and then

vanished gradually. So remarkable an instance of atmospherical

refraction had not been before witnessed by the oldest inhabitant of

Hastings. It was likewise observed at Winchelsea, and other places along

the coast. The day was remarkably hot, without a breath of wind

stirring.

As another instance of this refracting power of the atmosphere, Dr.

Vince, an English philosopher, was once looking through a telescope at a

ship, which was so far off, that he could only see the upper parts of

the masts. The hulk was entirely hidden by the bending of the water, but

between himself and the ship he saw two perfect images of it in the air.

These were of the same form and color as the real ship; but one of them

was turned upside down. And when Captain Scoresby was in the polar sea

with his ship, he was separated by the ice from that of his father for

some time, and looked out for her every day with great anxiety. At

length, one evening, to his utter astonishment, he saw her suspended in

the air, in an inverted position, traced on the horizon in the clearest

colors, and with the most distinct and perfect representation. He sailed

in the direction in which he saw this visionary phenomenon, and actually

found his father’s vessel by its indication. He was separated from the

ship by immense masses of icebergs, and at such a distance that it was

impossible to have seen her in her actual situation, or to have seen her

at all, if her spectrum had not been thus raised several degrees above

the horizon in the air by this most extraordinary refraction. It is by

this bending of the rays of light that the images of people are often

seen at a distance, and sometimes magnified to a gigantic size. We have

given an account of such an appearance in the Hartz mountains, in

Germany.

Another singular instance of the refracting power of the atmosphere, was

witnessed within the present year, (1854,) by Mr. Elliott, the aeronaut,

while ascending in his balloon from Petersburg, Virginia. After he had

ascended about three thousand feet he discharged some five pounds of

ballast, when he shot onward and upward with amazing rapidity till he

began to approximate to the clouds. He then discharged about five pounds

more of sand, the remainder of the bag, when he again darted upward

among the clouds, which were so dense as to wholly exclude all

terrestrial objects from his view, and of course he was lost to all

observers below. These discharges were distinctly seen by persons

watching him, and on the first occasion some one exclaimed that the

balloon had burst. While among the clouds, it seemed to him as if he was

in the midst of a large ground-glass globe, some two or three hundred

feet in diameter, against the side of which opposite to the sun, the

shadow of his balloon rested, some five or six times larger than the

corporeal one. About half-way between him and the shadow, which seemed

as if resting on the glass wall, another balloon was seen, of a size

between the shadow and the real one, resting as if in a vacuum, which

displayed every color of the original faithfully. He then saw another

Elliott, clad and with features like himself, and seemingly self-like.

He then extended his own fingers, when he was mimicked by his image; and

whether he extended one finger or more, or whatever he did, this figure

duplicated exactly. When he would cause his balloon to oscillate, this

balloon would move exactly like his. When he threw out more ballast to

elevate himself, this figure _sank down_ instead of rising with him; and

when he arose above the clouds into the rays of the unclouded sun, he

left the mimic aeronaut below him.

In the rays of the sun above the clouds he found it so warm as to cause

him to perspire freely, a state of heat never before experienced at this

hight, nearly twenty-four thousand feet, where the air is very rarefied

and generally very chilly. He then opened the valve for the purpose of

descending, and as soon as he had sunk one or two thousand feet, which

he ascertained by barometrical indications, he felt as if he had entered

an ice-house, and a cold chill seized his whole person. Here he again

met his mimic aerial voyager, whom he kept in company for some time,

from philosophical motives. Whenever he moved sideways, this _mum_

gentleman would move in the same direction. But when he moved up or

down, the duplicate would move in a directly opposite way; and when he

concluded to descend, the image moved upward until the tricolored flag

was out of sight, when he could see the car and the aeronaut still

standing in it as if in a basket attached to nothing. He continued to

look until his head was Robespierred, and finally, piece by piece, his

body, and, at last, his feet and basket, ascended out of his sight. Mr.

Elliott said that he had been up a hundred and one times, but never had

seen anything in the form of an illusion like this before.

[Illustration: SHIP REFRACTED IN THE AIR.]

But one of the most remarkable cases of atmospheric refraction of which

we have any record, is that which occurred at New Haven, Connecticut, in

the early settlement of the colony. The colonists had built a ship, and

freighted her for England with a valuable cargo, with which she sailed

from their harbor in the winter of 1647, having several of their

principal men on board. They were obliged to cut their way through the

ice to get out of the harbor; and the ship, never being heard of

afterward, was supposed to have foundered at sea. No tidings arriving of

the ship or of her fate, the colonists were deeply distressed, and “were

very earnest in their prayers, both public and private, that God would

in some way make manifest to them what had become of their friends.” In

the following June, a violent thunder-storm arose out of the north-west,

after which the atmosphere being very calm and serene, about an hour

before sunset, a ship of the dimensions and form of the one they had

lost, with all her canvas set and flags flying, appeared in the air,

coming up the harbor, her sails filled as though by a fresh gale, and

sailing against the wind, for the space of half an hour.

At length, as she came nearer, her maintop seemed to be blown off,

though left hanging in the shrouds; then, her mizzen-top; then all her

masting seemed blown away by the board; quickly after, her hulk

careening, she overset, and seemed to sink and vanish in the clouds, and

as these clouds passed away, the air where she was seen, was, as before,

perfectly clear. The crowd of spectators could distinguish the

appearance of the various parts of the ship, the principal rigging, and

such proportions as made them satisfied that this was indeed their ship;

and Mr. Davenport, the minister, declared, in public, that God, for the

quieting of the hearts of the people, had given them this extraordinary

exhibition and account of what he had done with their property and

friends. But science gives us a more natural and less miraculous

explanation of the matter, in the refracting power of the air when in

certain states; and the probability is, that the ship, thus seen in the

air, was some strange vessel (which they imagined looked like their own)

coming up the harbor before the breeze, and then driven off and wrecked

by the storm, which reached her after it had passed New Haven; or else

that it was, indeed, their own ship, which after being driven about for

months, was now coming back to her port, when she was thus caught in the

tempest and destroyed. And as confirming this view of the matter, it may

be added, in conclusion, that within the present century, it is said, a

similar refraction of a ship in the air, has been witnessed in the same

place.

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