!8 4 [Proc. B.N.F.C., 



in section H. Professor Ridgeway in this section advocated the 

 study of anthropology by all would-be administrators, and said 

 such could not rule any tribe or nation properly without under- 

 standing their history, laws, and customs. There were six excur- 

 sions — the Boyne tour, Bray, Powerscourt and Dargle, Rock of 

 Cashel and Holy Cross Abbey, Killaloe and Lough Derg, and 

 Athlone and Clonmacnoise. 



Mr. Thomas Anderson then read a paper on " The Geology 

 of the Dublin District." The neighbourhood of Dublin is remark- 

 able, he said, as being the centre where several great geological 

 systems meet. Approaching by sea, we get a glimpse of the oldest 

 rocks in the shape of the Hill of Howth on the right and Bray 

 Head on the left. They are of Cambrian origin, and are much 

 contorted and uptilted. From Killiney south for seventy miles 

 stretch the granite mountains and moorlands of Leinster. They 

 are of early old red sandstone age, and were intruded in the silurian. 

 Their formation took place at a time of tremendous activity and 

 disturbance in the earth's crust. Enormous masses of strata were 

 pushed up and folded, and the Leinster chain is the result of this 

 great earth movement. The pressure, operating from south-east, 

 gradually pushed up the silurian strata into an enormous arch, 

 and pari passu with this, granite magma flowed and filled the 

 contour of the arch. There were several movements of this nature 

 until the mountains attained a height of several thousand feet. 

 Long ages of denudation followed, and the silurian cap covering 

 the granite was by this means almost completely removed, revealing 

 a great granite mass — the greatest in the British Isles. The car- 

 boniferous period is well shown in the coast section north of 

 Dublin, where the overfolding of the limestone beds and the many 

 problems connected therewith render that coast most attractive to 

 geologists. Carboniferous limestone extends from Dublin to 

 Galway, and the enormous and prolonged denudation of this area 

 has worn down the strata to the fiat aspect it now bears as the 

 greatest central plain of Ireland. Coming down to later times, we 



