Astronomy 

 Atmosphere 



SCIENTIFIC SIDE-LIGHTS 



52 



to all celestial bodies, the sun has a far 

 slower proper motion in an opposite direc- 

 tion. The stars which shine in the evening 

 sky sink lower every day, until at length 

 they are wholly lost amid the rays of the 

 setting sun; while, on the other hand, 

 those stars which were shining in the morn- 

 ing sky, before the rising of the sun, recede 

 further and further from it. In the ever- 

 changing aspect of the starry heavens suc- 

 cessive constellations are always coming to 

 view. A slight degree of attention suffices 

 to show that these are the same which had 

 before vanished in the west, and that the 

 stars which are opposite to the sun, setting 

 at its rise and rising at its setting, had 

 about half a year earlier been seen in its 

 vicinity. From the time of Hesiod to Eu- 

 doxus, and from the latter to Aratus and 

 Hipparchus, Hellenic literature abounds in 

 metaphoric allusions to the disappearance 

 of the stars amid the sun's rays, and their 

 appearance in the morning twilight their 

 heliacal setting and rising. An attentive 

 observation of these phenomena yielded the 

 earliest elements of chronology, which were 

 simply expressed in numbers, while myth- 

 ology, in accordance with the more cheerful 

 or gloomy tone of national character, con- 

 tinued simultaneously to rule the heavens 

 with arbitrary despotism. HUMBOLDT Cos- 

 mos, vol. iii, p. 118. (H., 1897.) 



259. ASTRONOMY ORIGINATED 

 WITH THE MOON The light of the 

 moon was the first astronomical illumina- 

 tion. Science commenced with this dawn, 

 and age by age it has conquered the stars 

 and the immense universe. This sweet and 

 calm light releases our thoughts from ter- 

 restrial bonds and compels us to think of 

 the sky; then the study of other worlds 

 develops, observations increase, and as- 

 tronomy is founded. It is not yet the 

 heavens, and it is already more than the 

 earth. The silent star of night is the first 

 halting-place on a voyage towards the in- 

 finite. FLAMMARION Popular Astronomy, 

 bk. ii, ch. 1, p. 81. (A.) 



260. ASTRONOMY, PRECISION OF 



Eclipses Predicted Centuries in Advance 

 Traced Back Centuries in the Past Miss- 

 ing Date of Herodotus Supplied Uniform- 

 ity of Nature Proved. Now, on the con- 

 trary, with the much more precise knowl- 

 edge we have of the moon's motion, we are 

 in a position to calculate and foretell for a 

 great number of years, and even centuries 

 in advance, not only the general circum- 

 stances of eclipses of the moon, but even the 

 detailed course of eclipses of the sun. We 

 can even, by a retrospective examination, 

 give an account of all the circumstances 

 which an ancient eclipse should have pre- 

 sented in such or such a locality, and find 

 the precise date of certain historical events 

 of which the epoch is a subject of discussion. 

 An eclipse of the sun is a veritable rarity 

 for any given place. (Thus, for example, 

 there has not been one at Paris since May 



22, 1724; the nineteenth century has not a 

 single one; in the twentieth century, on 

 April 17, 1912, Paris will be just on the 

 limit of totality; but a true total eclipse, 

 of several minutes' duration, will not be 

 seen in the capital of France till August 11, 

 1999.) Herodotus relates that at the mo- 

 ment of a battle between the Lydians and 

 the Medes a total eclipse of the sun at once 

 stopped the stupefied combatants and put 

 an end to the war. Till recently historians 

 gave various dates for this event, from the 

 year 626 before our era down to the year 

 583 ; astronomical calculation, however, 

 proves that this battle took place on May 

 28 of the year 585 B. C. FLAMMARION 

 Popular Astronomy, bk. ii, ch. 9, p. 182. 

 (A.) 



261. ASTRONOMY SUPPOSED EX- 

 HAUSTED Reenforcement of Physics Has 

 Given It New Youth The Nature vs. the 

 Movements of the Heavenly Bodies. The 

 astronomy so signally promoted by Bessel 

 the astronomy placed by Comte at the head 

 of the hierarchy of the physical sciences 

 was the science of the movements of the 

 heavenly bodies. And there were those who 

 began to regard it as a science which, from 

 its very perfection, had ceased to be inter- 

 esting whose tale of discoveries was told, 

 and whose further advance must be in the 

 line of minute technical improvements, not 

 of novel and stirring disclosures. But the 

 science of the nature of the heavenly bodies 

 is one only in the beginning of its career. 

 It is full of the audacities, the inconsist- 

 encies, the imperfections, the possibilities of 

 youth. It promises everything; it has al- 

 ready performed much; it will doubtless 

 perform much more. The means at its dis- 

 posal are vast and are being daily aug- 

 mented. CLERKE History of Astronomy, pt. 

 ii, ch. 1, p. 177. (Bl., 1893.) 



262. ASTRONOMY, TRANSFORMA- 

 TION OF A New Epoch The Manifestation 

 of Universal Life Peaceful and Glorious 

 Conquests of Science. Moreover, astron- 

 omy presents us now with one of those 

 radical transformations which form an 

 epoch in the history of the science. It 

 ceases to be a figure and becomes alive. 

 The spectacle of the universe is transfig- 

 ured before our astonished minds. It is no 

 longer inert bodies rolling in silence in 

 eternal night that the finger of Urania 

 shows us in the depths of the heavens; it 

 is life life immense, universal, eternal, 

 unfolding itself in waves of harmony out to 

 the inaccessible horizon of an eternal in- 

 finite. What marvelous results! What 

 splendors to contemplate! What magnifi- 

 cent fields to traverse! WTiat a series of 

 pictures to admire in these noble and peace- 

 ful conquests of the human mind sublime 

 conquests which cost neither blood nor 

 tears, and where we live in the knowledge 

 of the truth, in the contemplation of the 

 beautiful. FLAMMARION Popular Astron- 

 omy, bk. i, ch. 1, p. 3. (A.) 



