ASTRONOMY. 



211 



this and other reasons it is conchided tliat there /s such a planet revolv- 

 ing at the distance of about 100, which is at present iii E. A. IV^ 40™ X. 

 P. D. 870. 



Similar considerations are applied to the next group of comets of 

 aphelion distances about 300, and evidence of a disturbing planet at this 

 distance also is adduced. Prof. Forbes has applied the method he has 

 used to the case of the comets which we know to revolve near Neptune, 

 and, without any knowledge of ISTeptune's real jwsition, he found that 

 the aphelion positions of these comets indicated the existence of a planet 

 in longitude 45'^. In fiict, Neptune is now in longitude 48°. From all 

 of which Prof. Forbes concludes the existence of at least one ultra-Xep- 

 tunian planet in the position indicated, i. e., for 1880, E. A. 11^ 40™ X. 

 P. D. 870 



The ljublication of Prof. Forbes's results has caused Mr. Todd, of 

 Washington, to print the results of some investigations he has made in 

 the motions of Uranus and Neptune as compared with Newcomb's tables 

 of these i^lanets. Proceeding by a graphical method he was led to the 

 conclusion that there must be a planet exterior to Neptune revolving in 

 an orbit inclined about 1^°, whose ascending node is at longitude 103"^, 

 and whose longitude is about 173^^, or, for 1881, March, its position is 

 E. A. 11^^ 37°^ N. P. D. 870. 



In other words. Prof. Forbes and Mr. Todd, proceeding on utterly 

 different data, have arrived at identically the same result. In each case 

 the data are iusufiBcient and the exact agreement is accidental. Still 

 it is noteworthy. 



It is extremely doubtful if such a planet would be recognizable by 

 its disk at this distance from the sun. Still, Mr. Todd made a search for 

 it with the 20-inch telescope at Washington, without success however. 

 The true method of research would be the accurate mapping of this 

 portion of the sky — a work of several years. 



Minor Planets. — The following discoveries were made in 1870 : 



Date. 



1879. 

 rebruary 17 - 

 FobruarV 28 - 

 March 22 - - 

 .Apra28 - - 

 Mav 17 - . - 

 May 21 - - - 

 June 13 - - 

 JulvO - - - 

 . July 27 - - - 

 August 7 - - 

 September 23 

 September 27 

 October 8 - 

 October 13 

 October 15 

 October 17 

 October 21 

 October 22 

 November 12 

 December 10 



So. 



■Xame. 



192 

 103 

 194 

 195 

 196 

 197 

 198 

 199 

 200 

 201 

 202 

 203 

 204 

 205 

 206 

 207 

 208 

 209 

 210 

 211 



Kausika - 

 Aml)rosia 

 Procno - 

 Eurycleia 

 PhilVmiela 

 Arete - - 

 Ampclla - 

 Byblis- - 

 Dynaraene 

 Penelope 

 Chryseis - 

 Pompeia - 

 CaUsto • 



Hersilia 



Dido 



Discoverer. 



Palisa. 



Coggia. 



Peters. 



Palisa. 



Peters. 



Palisa. 



Borrelly. 



Peters. 



Peters. 



Palisa. 



Peters. 



Peters. 



Palisa. 



Palisa. 



Peters. 



Palisa. 



Palisa. 



Peters. 



Palisa. 



Palisa. 



