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‘¢ A portion of the mound may still be seen overhanging 
the cliff, and if the section of it next the cliff be examined, 
the bones and charcoal may be easily observed. ~ 
‘I gave the particulars of this discovery to Mr. D Alton 
when he was about to publish his Memoir of Drogheda, and 
it is referred to in the first volume of his History of Drog- 
heda. I stated to Mr. D’Alton that there was no tradition 
of the origin of this vast funereal pile, but he quotes a passage 
from Dr. Hanmer’s Chronicles of Ireland, from which it 
would appear that a battle was fought between an army of 
marauders and Dermott Lamhdearg, King of Leinster, 
about the commencement of the fifth century, at Knock-na- 
cean, 7. e., the Hill of Heads, the marauders having landed 
at the ‘ Follesse of Skerries.’ 
<‘ Rude stone coffins, composed of the common flag-stones 
of the country placed together in the form of a coffin, with 
skeletons, are found very frequently in this neighbourhood. 
<¢ Although it is unconnected with the foregoing, I may as 
well state, as a matter of curiosity, that Mr. Burdon, about 
the same time, when visiting the Hill of Tara, discovered 
and brought home to me a regular joint of a basaltic column, 
brought, no doubt, in the days of Tara’s greatness from the 
Giant's Causeway. He discovered it accidentally; it was 
covered by the sod, and was not far from the pillar supposed 
to be the Lia Fail.” 
Rev. Samuel Haughton, Fellow of Trinity College, read 
a paper on *‘ The Equilibrium and Motion of elastic solid, 
and fluid Bodies.” , 
The object of the paper is to deduce, by the method of the 
‘ Mecanique Analytique’ of Lagrange, the laws of solid and 
fluid bodies from the same physical principles, and to discover 
by the same method the conditions at the limits. 
The principle from which Mr. Haughton deduces the 
equations is, that the molecules of solid and fluid bodies act on 
each other in the direction of the line joining them, with a 
