102 The President's Address. 



geologists, but Mr. Wallace has now given weighty reasons 

 for believing that this explanation is inadequate, and that 

 purely astronomical causes are insufficient to account for 

 such great climatic changes. He is of opinion that certain 

 concomitant geographical changes are also necessary, and 

 he thus adds to Croll's astronomical theory a modification 

 of the purely geographical explanation of climatic change 

 long ago advanced by Sir Charles Lyell in the " Principles 

 of Geology." The history of science presents many such 

 instances of the amalgamation of hypotheses. A theory 

 may for a long time be maintained until some new and 

 more perfect theory is offered in its place — in the heat of 

 intellectual excitement the older theory is rejected under 

 the belief that the newer one has rendered it unnecessary, 

 but in the course of time it is seen that the two are not 

 necessarily mutually exclusive, and some master worker 

 shows that they are both requisite for an adequate expla- 

 nation of the phenomena concerned. 



The Field Meeting held on the 3rd of July, when Major- 

 General Pitt-Eivers gave us the benefit of his large 

 experience on the occasion of our visit to the ancient earth- 

 works in the Forest, has opened up a line of work which 

 may enable our Club to do substantial service to 

 archaeology. At this meeting, in addition to our conductor, 

 we had with us Mr. W. L. Distant, one of the directors of 

 the Anthropological Institute ; Mr. B. H. Cowper, the 

 discoverer of the Loughton Camp ; and Mr. D'Oyley, the 

 surveyor of the earthworks ; to these gentlemen the thanks 

 of the Club are due. The history of these camps is quite 

 unknown, and their supposed founders come down to us 

 only through uncertain traditions which are valueless to the 

 scientific archaeologist. At the suggestion of our conductor 

 we therefore determined to attempt to settle the problem, 

 by raising an " Exploration Fund " for the purpose of open- 

 ing these earthworks, with a view to obtaining some relics 

 of their constructors. I have already had the pleasure of 

 informing you that the necessary permission has been 

 granted by the Forest Conservators, and the thanks of the 

 Club have been rendered to this body, and to our esteemed 



