

PRESIDENT'S ADDRESS. Ixxxix* 



GEOLOGY. 



The meeting of the British Association being held in Dublin, 

 Irish geology played a prominent part in the programme, and 

 various districts were dealt with. The results of the exploration 

 of the cave of Castlepook, near Doneraile, tend to show that the 

 cave is of pre-glacial age, and that Ireland and England have 

 not been joined together in glacial or post-glacial times. It has 

 been attempted by many different methods to reckon the lengths 

 of geological periods, but, though very positive statements are 

 sometimes made, it would seem that the question is still very far 

 from being solved. The Falls of Niagara have been used by 

 various observers for this purpose, the last estimate of their age 

 being calculated at 39,000 years, of the accuracy of which 

 amount the observer seems very confident. Nevertheless, the 

 first estimate, made in 1835 by Lyell, was 35,000 years, and 

 more modern observers have put the amount as low as 7,000, or 

 possibly considerably less. These immense discrepancies 

 illustrate the extreme unreliability of such calculations. At 

 the same time the actual history of the Falls, as worked out from 

 a study of their surroundings, is very interesting. One of the 

 most disastrous European earthquakes of recent times took place 

 on December 28th last, completely destroying Messina and other 

 neighbouring places and causing immense loss of life. It was 

 followed by a great sea wave, which did further damage, and 

 the levels of the ground in parts have been altered both by 

 subsidence and the contrary. An earthquake of probably equal 

 violence took place in Persia on January 23rd, affecting fifty 

 villages and causing the loss of many lives, but, fortunately, no 

 large town like Messina existed in the area of its greatest 

 violence. At home, in Dorset, the chief phenomenon which can 

 be placed under the present heading is the landslip which took 

 place on June xoth last about half-a-mile east of Lyme Regis in 

 the vicinity of the burning cliff, which first manifested itself in 

 January, 1908, and which I alluded to in my last address. This 

 subject has been ably treated in a paper by our Hon. Member, 



