530 COSMOS. 



ously directed to the same important end, present in their 

 laudable competition so much the more interest, as they tes- 

 tify by the selection of means to the present distinguished 

 condition of higher mathematical knowledge. 



contained the solution of the whole problem appeared in the 

 Connaissance des Temps pour Tan 1849. Adams laid the first 

 results which he had obtained for the disturbing planet before 

 Professor Challis in September, 1845, without having them 

 printed, and together with some alterations in October of the 

 same year, before the Astronomer Royal, still without making 

 them public. The latter received the final results of Adams, 

 with fresh corrections referring to a decrease of the distance, 

 in the commencement of September, 1846. The young Cam- 

 'bridge geometrician expresses himself upon the chronological 

 succession of the investigations which were directed to one 

 and the same object with as much modesty as self-denial : " I 

 mention these earlier dates merely to show that my results 

 were arrived at independently and previously to the publica- 

 tion of M. Leverrier, and not with any intention of inter- 

 fering with his just claims to the honour of the discovery. 

 For there is no doubt that his researches were first published 

 to the world, and led to the actual discovery of the planet by 

 Dr. Galle : so that the facts stated above cannot detract in 

 the slightest degree from the credit due to M. Leverrier." 

 Since, in the history of the discovery of Neptune, mention is 

 frequently made of an early share which the great Konigs- 

 berg astronomer took in the hope already expressed by Alexis 

 Bouvard (the author of the tables of Uranus) in the year 1834, 

 *' of the disturbance of Uranus by a yet unknown planet," it will 

 perhaps not be unacceptable to many readers of the Cosmos 

 if I introduce here part of a letter which Bessel wrote to me 

 on the 8th of May, 1 840 (therefore two years before his con- 

 versation with Sir John Herschel, during his visit to Colling- 

 wood) : " You request me to give you information as to the 

 planet beyond Uranus. I could indeed refer you to friends in 

 Konigsberg who, from misunderstanding, fancy that they know 

 more about the matter than I do myself. I chose as the sub- 

 ject of a public lecture delivered upon the 28th of February, 

 1840, the development of the connection between astrono- 



