128. 



present be idle to speculate ; it must evidently be much more 

 complicated than that of the ordinary globular clusters, which 

 themselves are intricate enough. Their resemblance to bo- 

 dies floating on a whirlpool is, of course, likely to set imagi- 

 nation at work, though the conditions of such a state are im- 

 possible there. A still more tempting hypothesis might rise 

 from considering orbital motion in a resisting medium ; but all 

 such guesses are but blind. He believes it is Lord Rosse's 

 purpose to make drawings of all these, based on rigorous mea- 

 surement, which may serve as evidence of change hereafter, 

 should such occur to any perceivable extent during the ages 

 that are yet to come. The instrument will henceforward be 

 regularly employed by an assistant, whom Dr. Robinson has 

 trained for the task, and on whose zeal and steadiness he can 

 rely ; and as it cannot be turned to the sky without revealing 

 something wonderful and glorious, he is certain that it will 

 yield an unfailing treasure to science, that it will realize the 

 high hopes of its generous master, and be one of the proudest 

 distinctions of his country. 



April 10th, 1848. 



REV. HUMPHREY LLOYD, D. D., Pkesident, 

 in the Chair. 



William Armstrong, Esq., Michael Barry, Esq., James 

 Christopher Kenny, Esq., Rev. Joseph Fitzgerald, and Rev. 

 William Graham, were elected Members of the Academy. 



The Rev. R. V. Dixon made some remarks on the diflfe- 

 rent conditions necessary to ensure a steam engine's working 

 at " full pressure," and at " uniform' pressure." 



" A steam engine is said to work at ' full pressure' when 

 the pressure of steam in the cylinder is equal to that in the 

 boiler, or rather (as strict equality cannot exist while the ma- 



