Conflagration 

 Conquest 



SCIENTIFIC SIDE-LIGHTS 



118 



which the heavens shall pass away with a 

 great noise; and the elements shall melt 

 with fervent heat: the earth also and the 

 works that are therein shall be burned up " 

 [2 Peter iii, 10]. For aught that is cer- 

 tainly known, the mere daily continuance of 

 the sun's light and heat may be due to 

 causes which need only be excited to unusual 

 activity to produce such a catastrophe. 

 . . . Sometimes there are outbursts in 

 the sun which suggest very significantly the 

 possibility of much more terrible, because 

 more general, catastrophes. PROCTOR Ex- 

 panse of Heaven, p. 199. (L. G. & Co., 

 1897.) 



585. CONFLAGRATION ON THE SUN 



" A Prairie on Fire " Chromosphere and 

 Prominences. At its base [of the sun's 

 corona], and in contact with the photo- 

 sphere, is what resembles a sheet of scarlet 

 fire. The appearance, which probably indi- 

 cates a fact, is as if countless jets of heated 

 gas were issuing through vents and spiracles 

 over the whole surface, thus clothing it with 

 flame which heaves and tosses like the blaze 

 of a conflagration " like a prairie on fire," 

 to quote the vividly descriptive phrase of 

 Professor Langley. This has received the 

 name of chromosphere. . . . 



Here and there masses of this hydrogen 

 mixed with other substances rise to a great 

 height, ascending far above the general level 

 into the coronal regions, where they float 

 like clouds, or are torn to pieces by contend- 

 ing currents. These cloud-masses are known 

 as solar " prominences," or " protuber- 

 ances," a non-committal sort of appellation 

 applied in 1842, when they first attracted 

 any considerable attention, and while it was 

 a warmly disputed question whether they 

 were solar, lunar, phenomena of our own at- 

 mosphere, or even mere optical illusions. It 

 is unfortunate that no more appropriate and 

 graphic name has yet been found for objects 

 of such wonderful beauty and interest. 

 YOUNG The Sun, ch. 6, p. 192. (A., 1898.) 



586. 



Simultaneous and 



Wild Agitation of the Magnetic Needle 

 Aurora Borealis. On September 1, 1859, 

 two astronomers, Carrington and Hodgson, 

 were observing the sun, independently of 

 each other, the first on a screen which re- 

 ceived the image, the second directly through 

 a telescope, when, in a moment, a dazzling 

 flash blazed out in the midst of a group of 

 spots. This light sparkled for five minutes 

 above the spots without modifying their 

 form, as if it were completely independent, 

 and yet it must have been the effect of a 

 terrible conflagration occurring in the solar 

 atmosphere. Each observer ascertained the 

 fact separately, and was for an instant daz- 

 zled. Now, here is a surprising coincidence: 

 at the very moment when the sun appeared 

 inflamed in this region the magnetic instru- 

 ments of the Kew Observatory, near Lon- 

 don, where they were observing, manifested 



a strange agitation; the magnetic needle 

 jumped for more than an hour as if infatu- 

 ated. Moreover, a part of the world was on 

 that day and the following one enveloped in 

 the fires of an aurora borealis, in Europe 

 as well as in America. It was seen almost 

 everywhere: at Home, at Calcutta, in Cuba, 

 in Australia, and in South America. Vio- 

 lent magnetic perturbations were mani- 

 fested, and at several points the telegraph 

 lines ceased to act. Why should these two 

 curious events not be associated with each 

 other ? FLAMMARION Popular Astronomy, 

 bk. iii, ch. 5, p. 290. (A.) 



587. CONFLICT OF TESTIMONY 



Personal Difference of Observation Univer- 

 sal among Astronomers. When the errors 

 dependent upon accidental circumstances 

 have all been eliminated, these measure- 

 ments still show differences between differ- 

 ent observers. They persist even when there 

 is no external reason discoverable. The fact 

 was first noticed in the annals of the Green- 

 wich Observatory for 1795. The astronomer 

 writes that he dismissed his assistant as un- 

 reliable because he had acquired the habit 

 of seeing all stellar transits half a second 

 too late. Not till many decades later was 

 the scientific honor of the assistant vindi- 

 cated. It was the celebrated German astron- 

 omer Bessel who proved that this difference 

 between two observers is only a special case 

 of a phenomenon of universal occurrence. 

 Bessel compared his own results with those 

 of other astronomers, and came to the sur- 

 prising conclusion that it is hardly possible 

 to find two observers who put the passage of 

 a star at precisely the same time, and that 

 the personal differences may amount to a 

 whole second. These observations were con- 

 firmed at all observatories. WUNDT Human 

 and Animal Psychology, ch. 18, 2, p. 268. 

 (Son. & Co., 1898.) 



588. - Surprise Disquali- 

 fies for Observation Disagreement in First 

 Accounts of the Sun's Halo. In this halo 

 we notice tongues of fire which emanate 

 from the sun and are contiguous to him. It 

 was during the eclipse of July 8, 1842, that 

 the attention of astronomers was first at- 

 tracted to these prominences, which shoot 

 forth round the moon like gigantic flames 

 of a rose or peach color (they had already 

 been seen with the naked eye, especially in 

 1239, in 1560, 1605, 1652, 1706, 1724, 1733, 

 and 1766, but astronomers believed them to 

 be optical illusions). The surprise produced 

 by this unexpected phenomenon did not per- 

 mit exact observations to be made, .so that 

 there was a complete disagreement between 

 the different accounts. Baily noticed three 

 enormous prominences, almost uniformly 

 distributed on the same side. 



Airy observed three, in the form of the 

 teeth of a saw, but placed at the summit. 

 Arago saw two at the lower part of the 

 disk. At Verona these flames remained vis- 





