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TEE POPULAR SCIENCE MONTHLY.— SUPPLEMENT. 



the destruction of this hypothetical planet as a 

 warning to evil-doers. If they continued in their 

 sins, they might not only bring destruction on 

 themselves, but on the world, which might burst, 

 as had that other world, and reduce the sun's 

 family by yet another planet. 1 



It was not until the discovery of Uranus by 

 Sir W. Herschel, in 1*781, that the speculations of 

 Kepler attracted scientific attention. Astrono- 

 mers had seen the three laws of Kepler inter- 

 preted physically by Newton, and had come to 

 regard those relations which admitted of no such 

 interpretation as mere coincidences. But when 

 the empirical law of distances, for which, as it 

 appeared, no reason in Nature could be assigned, 

 was found to be fulfilled by the new planet, as- 

 tronomers could not but regard the circumstance 

 as somewhat more than a mere coincidence. It 

 is strange to consider that had Neptune instead 

 of Uranus been discovered by Sir W. Herschel, 

 the very reverse would have been inferred. Mer- 

 cury's orbit, by Bode's law, should be 96, but 

 is really 91 ; that of Saturn's distance from Ura- 

 nus should be 192, but is really 188, so that 

 Bode's law is satisfactorily fulfilled by Uranus ; 

 but Neptune's distance from Mercury's orbit 

 should be 384, and is really but 296, which can- 

 not in any way be reconciled with the law. Sup- 

 posing Uranus unknown when Neptune was dis- 

 covered, the distance of Neptune would have 

 seemed too great by 104 for Saturn's next neigh- 

 bor (being 296 instead of 192), and too little by 

 88 for Saturn's next neighbor but one, according 

 to Bode's law of distances. Thus astronomers 

 would have inferred that Bode's law was errone- 

 ous (as indeed it is), and would not have thought 

 of looking for a planet between Mars and Jupiter. 

 As, however, by good fortune, Uranus was found 

 first, they inferred (mistakenly) that Bode's law 

 represents a real relation existing, no one could 

 say why, among the planetary orbits, and thence 

 concluded (rightly) that the space between Mars 

 and Jupiter is not vacant. 



A society was therefore formed — chiefly 

 through the active exertions of De Zach, of Gotha 



1 "We do not learn whether the warning was effec- 

 tive or not; but probably the evil-doers were not more 

 troubled by a danger affecting the whole of the human 

 race than by that which had long been described as 

 hanging over themselves in particular. The logical ef- 

 fect of the warning, one would suppose, must have 

 been to encourage that particular form of godliness 

 which is shown by anxiety about the sins of others. 

 For it was clearly very much to the interest of those 

 who did well to see that the evil-doers did not bring 

 about a catastrophe from which good and bad alike 

 could not fail to suffer. 



— to search for the missing planet. It consisted 

 of twenty-four astronomers under the presidency 

 of Schroeter. The zodiac, the highway of the 

 planets, was divided into twenty-four zones, one 

 of which was assigned to each member of this 

 Society for the Detection of a Missing World. 

 The twenty-four commenced their labors with 

 great zeal. When we consider that over the 

 region of the heavens which they were to ex- 

 amine at least a hundred planets, well within the 

 range of their telescopes, were traveling, we may 

 fairly wonder that they discovered nothing. Such, 

 however, was the result of their labors. After 

 they had been at work a considerable time, acci- 

 dent revealed to an astronomer outside their so- 

 ciety a body which was regarded for a long time 

 as the missing planet. 



Prof. Piazzi, while observing stars for his 

 catalogue, was led to examine very carefully a 

 part of the constellation Taurus, where Wollaston 

 had marked in a star which Piazzi could not find. 

 On the first day of the present century he ob- 

 served in this part of the heavens a small star, 

 which he suspected of variability, seeing that it 

 appeared where before no star of equal brightness 

 had been mapped. On January 3d he found that 

 the star had disappeared from that place, but an- 

 other, much like it, lay at a short distance to the 

 west of the place which it had occupied. The 

 actual distance between the two positions was 

 nearly a third of the moon's apparent diameter. 

 On January 24th (our observer was not too im- 

 patient, it will be seen) he transmitted to Oriani 

 and Bode, members of the Missing World Detec- 

 tion Society, an account of the movements of this 

 star, which had traveled toward the west till 

 January 11th or 12th, and had then begun to ad- 

 vance. He continued his labors till February 

 11th, when he was seized with serious illness. 

 Unfortunately, his letters to Oriani and Bode did 

 not reach those astronomers until nearly the end 

 of March, by which time the planet (for such it 

 was) had become invisible, owing to the approach 

 of the sun to the part of the heavens along which 

 the planet was traveling. 



But the planet was not lost. The sun passed 

 on his way through the region occupied by the 

 planet, and in September that region was again 

 visible at night. In the mean time the great 

 mathematician Gauss had calculated from Piaz- 

 zi's observations the real path of the planet. 

 Throughout September, October, November, and 

 December, search was made for the missing star. 

 At length, on the last day of the year 1801, De 

 Zach detected the planet, Olbers independently 



