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The Rev. Professor Haughton communicated the following 
Paper on the granites of the province of Leinster. 
“The granites of the south-east of Ireland occur in the 
counties of Dublin, Carlow, Kilkenny, Wicklow, and Wex- 
ford, and may be divided physically into two distinct groups. 
“1st. The chain of granite hills extending from Booters- 
town and Dalkey, county of Dublin, ina N.N.E., 8.5. W. 
direction, to Poulmounty, in the south of the county of Carlow, 
within five miles of New Ross. This granite chain has a 
‘length of sixty-eight miles, and a breadth varying from eight 
to fifteen miles. 
«« Qnd. The series of granite hills, occurring at intervals in 
the slate of the counties of Wicklow and Wexford, isolated 
from each other, and rising like islands through the slate. This 
group of granite hills lies between the main chain and the sea, 
and appears to be arranged in lines parallel more or less to the 
axis of the main chain. 
‘* These granite hills are about twenty in number, and 
extend fora distance of forty-three miles from Ballinaclash, 
county of Wicklow, to Camaross Hill, county of Wexford. 
«¢ Hitherto, so far as I am aware, no decisive proof of dif- 
ference of geological age has been discovered between these 
two groups of granites. They are both newer than the Silu- 
rian slates, which they penetrate and metamorphose. ‘The fol- 
lowing statement, which I have received from Dr. Griffith, to 
whom I communicated my results, contains the substance of 
what is known as to the relative geological age of these gra- 
nites. 
“* Atheneum Club, London, 
““* 12th May, 1855. 
‘“«¢ Dear Sir,—In reply to your query relative to the granites 
of the counties of Wicklow and Wexford, I would observe that in 
my view the district presents two distinct regions of igneous action, 
the products of different and probably distant periods. 
