OF THE ROYAL IRISH ACADEMY, 1846. 459 



you that its chair has been filled by two of your Presidents. 

 With the labours of Brinkley the Dublin Observatory will always 

 stand connected in the history of science. I am sure that it is un- 

 necessary for me to remind you of his researches connected with 

 the problem of the " Stellar Parallax," of which your Transactions 

 contain the first results that great problem, whose final solution 

 has at length been placed beyond question by the observations 

 of Bessel. Of the other and better known inequalities, which 

 affect the apparent places of the stars, all have been illustrated by 

 the observations made with the meridional circle of the Dublin 

 Observatory. In this important class of astronomical investigations, 

 the able director of the Armagh Observatory has had a dis- 

 tinguished share ; and the labours of Dr. Robinson have conferred, 

 as might have been expected, increased accuracy upon the result- 

 ing values of the constants. 



And here, Gentlemen, you will permit me to pause for a mo- 

 ment, and having named the name of Bessel, to offer a passing 

 tribute to his memory. He, who but a few months since occupied 

 the foremost place in the ranks of living Astronomers, is now no 

 more ! He died on the day which followed the last meeting and 

 anniversary of this Body ; and those among us who had the 

 happiness to form his acquaintance, during his short visit to 

 England, and to the British Association, four years ago, will be 

 able to sympathize with his personal friends, no less than with the 

 world of science, in deploring his loss. 



Of the astronomical and optical labours of the Earl of E-osse, 

 and of his great reflector the marvel of astronomical science it 

 is needless for me to speak. No one who was present when the 

 account of its construction, and of its first achievements, was given 

 in this room by Dr. Robinson, can readily forget it ; and for others, 

 the printed notice of that account, in the last number of our Pro- 

 ceedings, will give the fullest information we yet possess respect- 

 ing it. Even from this statement of its earliest trials, it is 

 manifest that the astronomical history of the nebula: will, ere long, 

 be re-made ; and it must be satisfactory to us to know, that the 

 noble artist has arranged a plan of systematic observation, directed 

 to these remote and mysterious portions of the universe, which 

 promises to reveal all that can be known, until a still higher 

 optical power (if such be practically possible) shall be applied to 

 their examination. The imagination is bewildered when it seeks 



