1856.] HAUGHTON — GRANITES OF IRELAND. 171 



I ought perhaps to add that to the west of the Mumbles, we find 

 a raised beach, while the contents of the caves show that the contour 

 of the coast must have been very different in the days of the extinct 

 quadrupeds to that which we at present see. 



3. Notice of the Recent Eruption of Mauna Loa, in Hawaii. 

 By W. Miller, Esq., H.M. Consul-general for the Sandwich 

 Islands. 



[Forwarded from the Foreign Office by order of Lord Clarendon.] 



(Abstract.) 



The late volcanic eruption* in the Sandwich Islands broke out in 

 August last, near the summit of Mauna Loa, which is 14,000 feet 

 high and sixty miles from Hilo, Byron's Bay, in Hawaii. 



The stream of lava, having a breadth of from two to three miles, 

 continued to flow in a north-east direction until the end of October, 

 when the lava-current, after having traversed a great part of the 

 dense forest, appeared to have been checked in its progress at about 

 ten miles from the town of Hilo. 



4. Experimental Researches on the Granites of Ireland. 

 By the Rev. Samuel Haughton, M.A., F.G.S., Professor of 

 Geology in the University of Dublin. 



PART I. — On the Granites of the South-east of Ireland. 



Introduction. 



I. Granites of the Main Chain. 



Elementary Minerals. 



Accidental Minerals. 



Chemical Composition of the Granites. 



Mineral Composition of the Granites. 



II. Isolated Granites of Wicklow and Wexford. 



First or Western Group of Isolated Granites. 

 Second Group of Isolated Granites. 

 Third Group of Isolated Granites. 

 Fourth Group of Isolated Granites. 

 Type-Granites of the South-east of Ireland. 



The granitic rocks of Leinster, or South-east of Ireland, occur in 

 the counties of Dublin, Carlow, Kilkenny, Wicklow, and Wexford, 

 and may be divided physically into two distinct groups (see Map, 

 fig. 1, p. 172) :- 



1 . The main chain of granite-hills, extending from Booterstown, 

 county Dublin, to Poulmonnty, in the south of the county of Carlow, 

 within five miles of New Ross. This granite-chain is unbroken 

 throughout its extent, and has a length of sixty-eight miles, and a 

 breadth varying from eight to fifteen miles. 



2. Besides the main chain there are about twenty isolated granitic 



* For detailed notices of this eruption of Mauna Loa, by Messrs. Coan and 

 Dana, see Silliman's American Journal of Science and Arts, vol. xxi. January and 

 March, 1856. 



