Xlii REPORT. — 1851. 



tical difficulties in the immediate execution of the design. I cannot doubt 

 that when a more explicit plan has been formed, another representation will 

 be accompanied with the same success which has attended every application 

 made by the Association for aid in a carefully arranged design. It will be 

 interesting to the Association to learn that the continuation of the observa- 

 tions on a Centauri at the Cape of Good Hope has fully confirmed the result 

 first obtained, — namely, that the parallax of that star exceeds nine-tenths of 

 a second, or that its distance from the sun is about twenty billions of miles. 

 So far as we have the means of judging, this star is our nearest neighbour in 

 the sidereal spaces. The attention of foreign astronomers is still directed to 

 the irregularities in tlie proper motions of stars, and the opinion seems to be 

 gaining ground that many of them are accompanied by non-luminous com- 

 panions. In our own solar system, the most remarkable discovery is that 

 (made independently, though on different days, in America and in England) 

 of a dusky ring interior to the well-known rings of Saturn. It now appears 

 that it had been seen several years before ; but it then attracted no attention. 

 How such a ring is composed, and how sustained, are questions upon which 

 perhaps the physical astronomer may long employ himself. But the disco- 

 very for which the year will be most frequently cited is that of tliree addi« 

 tional planets, included in the same planetary space — between Mars and Ju- 

 piter — in which eleven others had been previously found. The last of these 

 (Irene) discovered by Mr. Hind, observer in the private observatory of Mr. 

 Bishop, forms the fourth of his list, — and makes his number the greatest 

 that any one man has ever discovered. Some time since, a grant was made 

 by the British Government for the perfection of the Lunar Theory and Lunar 

 Tables on which Prof. Hansen, of Gotha, had been engaged, but whose pro- 

 gress was stopped by the interruption of funds in consequence of the unhappy 

 Schleswig-Holstein war. I understand, that with the aid of this grant, 

 equally honourable to the British Government and to the foreign philo- 

 sopher, the work is now rapidly advancing. I have reason to believe that 

 the theories of Uranus and Neptune are now undergoing careful revision ; 

 and I trust that one of the elements most urgently required, namely, the 

 mass of Neptune, will be supplied from observations of Neptune's satellite 

 made with the large telescopes to which I have alluded. 



At the Edinburgh meeting, the attention of the Mathematical and Physical 

 Section was called by M. O. Struve (there present) to the total eclipse of 

 the sun which is to occur on the 28th day of the present month ; and the 

 General Committee appointed a Committee of members of the Association 

 to draw up Suggestions for the observation of the eclipse. These Suggestions 

 have been extensively distributed both at home and abroad : and I am happy 



