256 A HISTORY OF 



1. In the reception-room, Leinster House, is a small 

 portrait of Thomas Braughall, by Comerford, the label on 

 which states that he was an active member of the Society 

 for many years, and an honorary secretary from 1792 

 to 1 7 98. Among the Haliday Pamphlets ( 1 803), mcccxxxviii. 

 3, is an elegy inscribed to the memory of Thomas 

 Braughall. 



2. Sir William Rowan Hamilton was born in Dublin in 

 1805, and in 1827 became Royal Astronomer for Ireland. 

 He was not only a great mathematician and metaphysician, 

 but also a poet. Hamilton twice obtained the gold medal 

 of the Royal Society on the first occasion for his great 

 optical discovery as to systems of rays, which disclosed a 

 new science of optics, involving as it did the discovery of 

 two laws of light ; on the second occasion for his theory of 

 a general method of dynamics. His very important work, 

 Lectures on Quaternions appeared in 1853. ^ n 1837 Hamil- 

 ton was elected President of the Royal Irish Academy. 

 From early youth he was distinguished as a linguist, and he 

 wrote many poems and sonnets. Wordsworth, Coleridge, 

 and Southey were numbered among his personal friends. 

 Sir William died in 1865, and the Rev. Robert P. Graves 

 published a memoir of him, in two volumes. 



3. Charles Haliday, merchant, born in Dublin in 1789, 

 was a member of the corporation for improving the harbour 

 of Dublin, and superintending the lighthouses on the Irish 

 coast. Haliday published a number of pamphlets on social 

 questions. He was a deeply-read antiquarian, and, after his 

 death, Mr. J. P. Prendergast edited his Scandinavian Kingdom 

 of Dublin, which was the substance of two learned com- 

 munications made by Haliday to the Royal Irish Academy. 

 He died in 1866, and after his death Mrs. Haliday pre- 

 sented to the Academy her husband's splendid collection of 

 pamphlets and tracts relating to Ireland, together with 

 his portrait. The tracts extend from the year 1578 to 

 1859, and the pamphlets from 1682 to 1859, tne f rmer 

 being comprised in 543 boxes, and the latter in 2209 

 volumes. 



