JANE AND ANNA MARIA PORTER,SHOOTING STARS AND METEORIC SHOWERS
From every region of the globe and in all ages of time within the range of history, exhibitions of apparent instability in the heavens have been observed, when the curtains of the evening have been drawn. Suddenly, a line of light arrests the eye, darting like an arrow through a varying extent of space, and in a moment the firmament is as sombre as before. The appearance is exactly that of a star falling from its sphere, and hence the popular title of shooting star applied to it. The apparent magnitudes of these meteorites are widely different, and also their brilliancy. Occasionally, they are far more resplendent than the brightest of the planets, and throw a very perceptible illumination upon the path of the observer. A second or two commonly suffices for the individual display, but in some instances it has lasted several minutes. In every climate it is witnessed, and at all times of the year, but most frequently in the autumnal months. As far back as records go, we meet with allusions to these swift and evanescent luminous travelers. Minerva’s hasty flight from the peaks of Olympus to break the truce between the Greeks and Trojans, is compared by Homer to the emission of a brilliant star. Virgil, in the first book of the Georgics, mentions the shooting stars as prognosticating weather changes:
“And on, before tempestuous winds arise,
The seeming stars fall headlong from the skies,
And, shooting through the darkness, gild the night
With sweeping glories and long trains of light.”
Various hypotheses have been framed to explain the nature and origin of these remarkable appearances. When electricity began to be understood, this was thought to afford a satisfactory explanation, and the shooting stars were regarded by Beccaria and Vassali as merely electrical sparks. When the inflammable nature of the gases became known, Lavosier and Volta supposed an accumulation of hydrogen in the higher regions of the atmosphere, because of its inferior density, giving rise by ignition to the meteoric exhibitions. While these theories of the older philosophers have been shown to be untenable, there is still great obscurity resting upon the question, though we have reason to refer the phenomena to a cause exterior to the bounds of our atmosphere. Upon this ground, the subject assumes a strictly astronomical aspect, and claims a place in a treatise on the economy of the solar system.
The first attempt accurately to investigate these elegant meteors was made by two university students, afterward Professors Brandes of Leipsic, and Benzenberg of Dusseldorf, in the year 1798. They selected a base line of 46,200 feet, somewhat less than nine English miles, and placed themselves at its extremities on appointed nights, for the purpose of ascertaining their average altitude and velocity. Out of twenty-two appearances identified as the same, they found,
7 under 45 miles
9 between 45 and 90 miles
5 above 90 miles
1 above 140 miles.
The greatest observed velocity gave twenty-five miles in a second. A more extensive plan was organized by Brandes in the year 1823, and carried into effect in the neighborhood of Breslaw. Out of ninety-eight appearances, the computed heights were,
4 under 15 miles
15 from 15 to 30 miles
22 from 30 to 45 miles
33 from 45 to 70 miles
13 from 70 to 90 miles
6 above 90 miles
5 from 140 to 460 miles.
The velocities were between eighteen and thirty-six miles in a second, an average velocity far greater than that of the earth in its orbit.
The rush of luminous bodies through the sky of a more extraordinary kind, though a rare occurrence, has repeatedly been observed. They are usually discriminated from shooting stars, and known by the vulgar as fire-balls; but probably both proceed from the same cause, and are identical phenomena. They have sometimes been seen of large volume, giving an intense light, a hissing noise accompanying their progress, and a loud explosion attending their termination. In the year 1676, a meteor passed over Italy about two hours after sunset, upon which Montanari wrote a treatise. It came over the Adriatic Sea as if from Dalmatia, crossed the country in the direction of Rimini and Leghorn, a loud report being heard at the latter place, and disappeared upon the sea toward Corsica. A similar visitor was witnessed all over England, in 1718, and forms the subject of one of Halley’s papers to the Royal Society. Sir Hans Sloane was one of its spectators. Being abroad at the time of its appearance, at a quarter past eight at night, in the streets of London, his path was suddenly and intensely illuminated. This, he apprehended at first, might arise from a discharge of rockets; but found a fiery object in the heavens, moving after the manner of a falling star, in a direct line from the Pleiades to below the girdle of Orion. Its brightness was so vivid, that several times he was obliged to turn away his eyes from it. The stars disappeared, and the moon, then nine days old, and high near the meridian, the sky being very clear, was so effaced by the lustre of the meteor as to be scarcely seen. It was computed to have passed over three hundred geographical miles in a minute, at the distance of sixty miles above the surface, and was observed at different extremities of the kingdom. The sound of an explosion was heard through Devon and Cornwall, and along the opposite coast of Bretagne. Halley conjectured this and similar displays to proceed from combustible vapors aggregated on the outskirts of the atmosphere, and suddenly set on fire by some unknown cause. But since his time, the fact has been established, of the actual fall of heavy bodies to the earth from surrounding space, which requires another hypothesis. To these bodies the term aërolites is applied, signifying atmospheric stones, from αηρ, the atmosphere, and λιθος, a stone. While many meteoric appearances may simply arise from electricity, or from the inflammable gases, it is now certain, from the proved descent of aërolites, that such bodies are of extra-terrestrial origin.
Antiquity refers us to several objects as having descended from the skies, the gifts of the immortal gods. Such was the Palladium of Troy, the image of the goddess of Ephesus, and the sacred shield of Numa. The folly of the ancients in believing such narrations has often been the subject of remark; but, however fabulous the particular cases referred to, the moderns have been compelled to renounce their skepticism respecting the fact itself, of the actual transition of substances from celestial space to terrestrial regions; and no doubt the ancient faith upon this subject was founded on observed events. The following table, taken from the work of M. Izarn, Des Pierres tombées du Ciel, exhibits a collection of instances of the fall of aërolites, together with the eras of their descent, and the persons on whose evidence the facts rest; but the list might be largely extended.
Some of the instances in the table are of sufficient interest to deserve a notice.
A singular relation respecting the stone of Ensisheim on the Rhine, at which philosophy once smiled incredulously, regarding it as one of the romances of the middle ages, may now be admitted to sober attention as a piece of authentic history. A homely narrative of its fall was drawn up at the time by order of the Emperor Maximilian, and deposited with the stone in the church. It may thus be rendered: “In the year of the Lord 1492, on Wednesday, which was Martinmas eve, the 7th of November, a singular miracle occurred; for, between eleven o’clock and noon, there was a loud clap of thunder, and a prolonged confused noise, which was heard at a great distance; and a stone fell from the air, in the jurisdiction of Ensisheim, which weighed two hundred and sixty pounds, and the confused
