President's Address, 3 



a far more advantageous position than was enjoyed by our 

 predecessors in the discussion of these problems. It is 

 impossible to refrain from re-examining long-established be- 

 liefs in the light of this newer knowledge, and as impossible 

 to resist the changes of opinion to which such a review must 

 inevitably lead. 



Among the important contributions from recent deep-sea 

 research towards an enlargement and readjustment of the 

 philosophy of geology, I shall briefly mention a few of the 

 more prominent, and devote the main part of this address to 

 a detailed exposition of one of these. 



1. It has now been conclusively established that the 

 deposits which are gathering over the floor of the wider 

 and deeper parts of the ocean, have no counterpart whatever 

 among the sedimentary rocks visible on the land. Various 

 inferences may legitimately be drawn from this fact, but 

 that to which it most obviously and directly leads is, that 

 the land has never lain beneath the deeper and wider parts 

 of the ocean. Yet we have only to turn to many familiar 

 geological writings to see how wide-spread has been the 

 belief that land and sea have been constantly changing 

 places, and that some of the sedimentary rocks that form the 

 dry land were accumulated in abysmal depths of the sea. 

 Had this behef been well founded, it is incredible that 

 nowhere on the land should any trace of such deposits be 

 found, as have been discovered to spread over the floor of the 

 deep sea. I have elsewhere tried to show how strongly this 

 evidence supports the view of the aboriginal character of the 

 oceanic and terrestrial areas of the globe.^ 



2. A second branch of investigation of momentous signifi- 

 cance in geological speculation is the determination of the 

 range of temperature in the ocean, and the distribution of 

 submarine climates. The fact, now brought to light, that 

 the great body of the ocean water is cold, and that in the 

 deeper abysses, even at the equator, the temperature sinks 

 towards and even below the freezing-point of fresh water, 

 casts a totally new light on the question of the distribution 



^ Jour. Roy. Geog. See, 1879; also Geological Essays at Home and 

 Abroad, 1882, p. 312. 



