﻿Vol. 64.] ANNIVEESART ADDEESS OF THE PRESIDEl^T. Ixix 



Percy Leonard Addison, Assoc.M.Inst.C.E., was born at 

 Glasgow on December 25th, 1855, and died at Bigrigg, Cumberland, 

 on jN'ovember 14th, 1906. He was Assistant Resident Engineer on 

 the Lancashire and Yorkshire Railway from 1874 to 1878, and 

 subsequently Assistant Engineer on the Eastern Bengal Railway. 

 Erom 1883 to 1891 he superintended the mines of Messrs. D. & 

 J. Ains worth, at Cleator in Cumberland. He became a Eellow of 

 this Society in 1888, and in 1890 contributed a description of the 

 Cleator Iron Company's barytes and umber-mines and refining- 

 mills to the Proceedings of the Institution of Civil Engineers. 



The Published Work of the Geological SociEir of London 



DURING THE EiRST CeNTURY OF THE SoCIETY's EXISTENCE. 



In the Address which I had the honour of presenting at the 

 Centenary Celebration of the Society last September, I gave a 

 sketch of the state of geological science at the end of the eighteenth 

 and the beginning of the nineteenth century. I then endeavoured 

 to show amidst what diverse currents of theoretical opinion, 

 leading to prolonged and acrimonious controversy, the Geological 

 Society took its rise. I now propose to resume the continuation of 

 this subject and to trace, as far as may be possible within the 

 limits of an Anniversary Discourse, the main features of the work 

 done by this Society, from which such influence has sprung as, 

 during the first hundred years of its existence, the Society may 

 have been able to exert upon the progress of our science. Obviously 

 by far the largest share of this influence must be ascribed, rather 

 to the independent labours of the more active and eminent Eellows 

 of the Society than to any corporate action of the Society itself. 

 When we look back upon the long roll of our membership, with its 

 crowded procession of illustrious names, we must admit that the 

 renown which these names have won in the literature of science 

 has in large measure arisen from writings that were neither 

 communicated to nor published by the Society. Though such men 

 as MaccuUoch and Buckland, Sedgwick and Murchison, Lyell and 

 De la Beche, Darwin and Owen, were loyal and helpful members of 

 our association, their fame rests mainly on what they gave to the 

 world in other publications than ours. Nevertheless, the well- 

 known connection of such men with the Geological Society was 

 unquestionably at the time a source of strength to our body, and 



