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From Scientific American, by special permission of Munn & Company.
No conception whatever can be had if this is true, the entire orbit traversed of the magnitude of the visible universe by the earth around the sun, that mighty until the distances of the stars are known. ellipse, shrinks and subsides into nothNone of the millions of the human beings ingness, his mind was simply submerged that have lived and died knew the dis- by the immensity of the idea, and all it tance of even one star from the earth led to.
For twenty years he toiled in until within the last seventy years. To an observatory making measurements all who lived before the advent of mod
every accuracy possible without ern astronomy, the stars were points telescopic aid. And he failed to detect in a rigid firmament, only a short dis- the slightest displacement of any star tance “above" the earth. They were throughout the year. For it is certain made to give light to the earth's inhabi- that if the earth moves around the sun, tants, a belief incredible to relate, still the stars in position at right angles to lingering in the minds of some. Before the plane of the orbit must shift to and A. D. 1542, ignorance was at its lowest fro at intervals of six months corresponddepth. But in that auspicious year Co- ing with the displacement of the earth pernicus gave his book to the world from side to side of its majestic pathway. teaching that the earth revolves around So he taught that the earth is at rest. the sun. Of course the people raised He could not force himself to admit that strenuous opposition. This was expect- the diameter of the orbit of the earth ed. But unrest and perplexity filled at as seen from any star is next to nothleast one of the ablest minds in Europe, ing, and that the earth is next to that of Tycho. From the days of Aris- nothing, and man an infinitesimal so totle and Ptolemy, the theory that the minute that no combination of figures sun revolves around the earth dominated is able to tell how small he is. Tycho men's minds. Not one law could be could measure four minutes of arc with discovered so long as it was believed some approach to accuracy; still he that the earth is the center of the uni- could not detect the slightest displaceverse and at rest. Copernicus upset this ment of a star. He at once knew that doctrine, and made the sun the center the stars were not less than one thousand of planetary motion. The great Tycho times farther away than the sun. SatBrahe actually rejected this basic truth urn at that time was the known limit of of nature. His mathematical powers the solar system, and if the hypothesis must have told him that Copernicus was of Copernicus were true, the stars must right in asserting that the earth moves be at least one hundred times more disaround the sun. But when he saw that tant. This vast space again
whelmed his mind. He argued that vented. This is an instrument to be Nature would not so waste space.
But attached to the eye-end of a telescope. Copernicus advanced arguments that It contains fixed and movable spider's Tycho could not overthrow, so Tycho threads, and it can measure excessively compromised. He made the five plan small angles and intervals.
It was ets revolve around the sun, and the sun crude at first, but during the succeeding around the earth, immovable in the two centuries the most accomplished center of the universe. At that epoch, mechanics applied their skill in making it is probable that if Tycho had had an it as perfect as anything wrought by instrument capable of measuring one sec human hands. At present it is able to ond of arc and had he tested it on any measure the diameter of a spider line. star, the Copernican system would have The object of making it of such extreme been crushed. For he would have dis accuracy is to be able to measure the covered that the stars do not shift even diameter of the earth's orbit as seen one second in six months. For with an from the stars. For next to nothing is annual shifting of one second of an arc the diameter seen from stellar distances. the star in question would have been Passing the labors of the Herschels known by Tycho to be 206,265 times and the Struves and many other eminent more distant than the sun. Medieval astronomers, who made use of every minds would have collapsed and an inde conceivable method of finding the disfinable fear would have settled down on tance of a star, we descend rapidly to mankind, when thinking of its littleness. Bessel and Henderson, two illustrious
Matters move on apace. Tycho died, observers, who finally succeeded, and and the Copernican doctrine spread. reaped the reward of two centuries of Then came Galileo with his little tele labors surpassing those of Hercules. scope, and pointed it full on the distant Bessel, at last, in 1840, found the disstars in A. D. 1610. This aroused Eu tance of the star 61 Cygni. He used a rope, and the exciting search began. different kind of telescope, the heliometer Astronomers now armed with instru with a divided object glass.
He emments that magnified were able to de ployed the method known as triangulatect far less displacements of stars than tion. He selected.two stars adjacent to could be detected by Tycho. And they 61 Cygni and measured a network of began to watch. Thus they noted the triangles, whose sides were the distances position of a star, its direction in space from star to star and from each star to and its distance from other nearby stars 61 Cygni. He repeatedly measured and recorded these determinations. In these angles from October, 1837, to six months they repeated the process March, 1840, and had the extreme good with great care. They were dumb fortune to see 61 Cygni move. And the founded. Although the earth had moved direction of motion was as it should be, from its first place, by the diameter of if caused by the annual circuit of the its mighty orbit, no trace of motion, earth. He found that if we go to 61 however minute, could be detected in Cygni, turn and look this way with a the stars, even in a telescope that mag powerful telescope and micrometer, the nified two hundred times. A number of distance of the earth from the sun would great astronomers tried their hands measure 0.3483 second of arc,
The arc from 1542 to 1650, a period of 108 years, of any circle in length equal to the rawith total failure as a result, Bradley dius contains 206,265 seconds, which and Molyneaux detected a motion of divided by 0.3483 equals 590,000. That stars; but in a direction opposite to any is, the star is at the colossal distance of caused by the motion of the earth. This 590,000 times that of the sun.
To rewas the aberration of light.' Other as duce this to miles, multiply by 93 million. tronomers after elaborate trials with the The result is so enormous that the ablest most nearly perfect instruments that mathematicians never try to begin to could be made, failed utterly.
think about it. Light, known to move About 1650 the micrometer was in with the unthinkable speed of 186,000
AS IT STANDS TODAY IN UNION DEPOT, CHATTANOOGA, TENN.
Where it was placed by the N. C. & St. L. Ry. Co. The following article, which appeared in the Kennesaw 'Gazette" of March, 1886, shows that the old "General" has had an eventful life:
"This famous locomotive is still on the Western & Atlantic Railroad, pulling a train. She is one of 'the old issue'; but is retained in service, although her capacity is rather limited when compared with the big 'ten-wheelers' and other modern locomotives which the ever wide-awake Western & Atlantic Railroad Company now possess.
"It is a matter of national knowledge that the 'General' was captured by twenty-two Federal soldiers in disguise, April 12, 1862, at Big Shanty, (known as the Andrews raid) and the attempt was made by them to escape with her and burn the bridges on the W. & A. R. R., etc. Their chase from Big Shanty to a point near Ringgold and the capture of the entire party are well known facts. It is not known, however, that the General' was
almost under fire of the Federal batteries at the eat battle of Kennesaw Mountain, June 27, 1864. When the battle began during the early morning General Johnston sent up a train load of ammunition, etc., to the Confederate lines at the eastern base of Kennesaw Mountain. The ammuntition, etc., was unloaded and carried to the front as quickly as possible, but the engine and train were detained at that point by order of General Johnston, to carry back the wounded at the close of the battle. During the entire morning the 'General' and her train stood at the point where now is the station Elizabeth, and some of the Federal bomb-shells, Aying over the Confederate entrenchments, exploded almost in her neighborhood. In the afternoon wounded soldiers from Featherstone's division and others in that portion of the field were placed aboard the train, and the 'General'
brought them down to Marietta, and thence on to Atlanta.
“The General' was also the last W. & A. R. R. engine to leave Atlanta when Hood's army evacuated it, and it was thought just before she left that it would be impossible to take her away, but they managed to get her safely out, and she went southward with a train load of refugees, war material, etc."
miles during one second of time, requires with this degree of accuracy. A star nine years to traverse the abyss. Before with one-tenth of a second parallax is this work of Bessel, Henderson, in the 2,062,650 times more remote than the observatory at the Cape of Good Hope, These are “near-by stars," for made extended observations the there are millions of stars so distant that bright star Alpha Centauri, not visible in no instrument, however accurate, can the United States. His instruments ever hope to secure a parallax. It is were not nearly so accurate as those of time now to put in the term “next to Bessel; yet he detected a displacement nothing" again for all things terrestrial. of the star. Maclear in 1839-40 made That is, the thickness of a spider thread more accurate measurements, and later would obscure the entire orbit of the observers with far better instruments earth in its mighty sweep around the have finally deduced a parallax of 0.75 sun, as seen from the distant stars. And second of arc.
Parallax means the angle all agree that a spider line is next to subtended by the radius of the earth's nothing, so the astronomer Tycho reorbit as seen from a star. Now 206, jected the true order of Nature simply 265 divided by 0.75 equals 275,020, the because of its mind-crushing magnitude number of times that Alpha Centauri and splendor. He had not the fortiis more distant than the sun. This is tude to admit the infinitesimal dimen25 trillion miles; and that star is our sions of the earth and man. All kind nearest neighbor, so far as is known. of estimates have been made as to the Light requires 4.3572 years to reach us probable radius of that part of the unifrom the nearest neighbor our sun has. verse visible in the greatest telescope. But there are so many stars whose dis Opinions vary between the limits of tances are so much greater than these 4,000 to 15,000 light years. That is, two, that the 25 trillion miles is used with a radius of 15,000, the diameter merely as a yard-stick to measure them. would be so immense that light would Of late these minute displacements of require 30,000 years to traverse it. The stars
measured on photographic opinion of the writer is for the 30,000 plates after long exposure to the stars. yet no positive proof is possible. This Great attention is paid to parallax de opinion is based on photometric grounds, terminations, for without them we must The word millions has for long been used forever remain ignorant of even approx in telling the number of the stars. But imate dimensions of the sidereal struc billions now appear to be more approture. Some astronomers think that so priate. Each one is a hot sun, and each great precision is now had that paral may be attended in many cases by inlaxes of 0.1 second of arc are obtained. habited worlds. And perhaps fifty stars are measured
HOW THE “KID” BEAT THE BANDITS.
BY J. MAYNE, BALTIMORE.
Fred L-- was known as a “big cub operator,” for he was only an overgrown “kid,” having just entered his twentieth year. He had been despatching for about a year at Welsh's Spur, some twenty miles from Butte, on the Northern Pacific line.
Welsh's Spur was a very small and unimportant station. Fred acted as both train despatcher and station agent.
Sometimes there was heavy freight to handle, and Lute Kelso was the general roustabout. Besides this duty, Lute did the switching and looked after whatever else came up.
Lute and the “Kid” were solid chums, and ready to fight for one another at the "drop of a hat." In the rear of the little building that served as both office and freight room, Fred and Lute slept
PRESENT STATION AT MURFREESBORO, TENN, On Nashville, Chattanooga & St. Louis Railway, where the great battle of Murfreesboro was fought,
December 31, 1862, to January 3, 1863.
Courtesy N. C. & St. L. Ry. But the boys passed many pleasant fled sounds resembling human voices days and nights in the cosy, snug little were heard. office hugging the warm coal stove, and “Somebody must be outside, Kid,” listening to the wild, hoarse ravings of said Lute. “ 'Pears to me I hear voices." the tempest without. And so the time Listening an instant, the Kid went passed along
to the window and peered around the
blinds. Blank darkness outside! NothOne cold, tempestuous night in De ing heard but the feathery snow dancing cember, the boys were sitting around against the panes, and the remote wail the comfortable stove. Without, in of winds. tense darkness prevailed; the fine pow “No, nothing but the storm,” redery snow was sifting down lightly, while marked Fred, resuming his seat by the the gale was shrieking like a hundred cheery stove. mad demons. It was about 11 o'clock. For some time silence fell between Within less than three quarters of an the two. Both sat listening to the