Address of the President. 21 



May 1863, writes: — "Thus there were two extremes" (iu ac- 

 countiug for the deposition of the fomiations) : " I have been 

 led to adopt an intermediate course. I could not admit the 

 possibility of river -action, as it now exists, having in any 

 length of time excavated the present valleys and spread out 

 old alluvia ; neither was it possible to admit purely cataclys- 

 mic action in cases where the evidences of contemporaneous 

 old laud-surfaces and of fluviatile beds were so common. But 

 with river-action of greater intensity, and periodical floods im- 

 parting a torrential character to the rivers, the consequences 

 of joint operation are obtained, and the phenomena admit of 

 more ready explanation. I long had proposed the separation 

 of the gravels into the high-level gravels and low-level gravels, 

 and shown that the former were older than the latter. I was, 

 however, at one time disposed to adopt, in part, some of the 

 vie\\s of M. EUe de Beaumont with regard to the cataclysmic 

 action in preference to the slower action of rivers ; but further 

 research, and the discovery of land and fresh-water shells in 

 so great a number of low-level gravels, and in some of the 

 high-level gravels, and especially the striking e\T.dence even- 

 tually afforded by the beds of St. Acheul, and by the higher 

 level gravels around Paris, satisfied me that river-action pecu- 

 liar to each valley commenced with the high-level gravels ; 

 while the mass of debris and the large blocks present in the 

 beds indicate the action of a large body of water and ice-trans- 

 port. I conceive that the hypothesis brought forward in 

 this paper gives consistency to the whole subject. It brings 

 do\vn the large mammalia to a period subsequent to that when 

 the extreme glacial conditions prevailed, and closer to our own 

 times." . . . "And" (the formations and deposits) "de- 

 pendent upon one prolonged and uniform set of operations in 

 accordance with the climatal conditions, and necessarily result- 

 ing from them." 



Thus it will be seen that the unprejudiced working of a 

 candid observer can modify preconceived views or theories ; 



