ADDRESS. O 



liable from time to time to be upheaved by some stupendous internal 

 force akin to that which gives rise to the volcano and the earthquake. 

 Hutton further perceived that not only had the consolidated materials 

 been disrupted and elevated, but that masses of molten rock had been 

 thrust upward among them, and had cooled and crystallised .in large 

 bodies of granite and other eruptive rocks which form so prominent a 

 feature on the earth's surface. 



It was a special characteristic of this philosophical system that it 

 souo-ht in the changes now in progress on the earth's surface an explana- 

 tion of those which occurred in older times. Its founder refused to 

 invent causes or modes of operation, for those with which he was familiar 

 seemed to him adequate to solve the problems with which he attempted 

 to deal. Nowhere was the profoundness of his insight more astonishing 

 than in the clear, definite way in which he proclaimed and reiterated his 

 doctrine, that every part of the surface of the continents, from mountain- 

 top to sea-shore, is continually undergoing decay, and is thus slowly 

 travelling to the sea. He saw that no sooner will the sea- floor be 

 elevated into new land than it must necessai-ily become a prey to this 

 universal and unceasing degradation. He perceived that, as the transport 

 of disintegrated material is carried on chiefly by running water, rivers 

 must slowly dig out for themselves the channels in which they flow, and 

 thus that a system of valleys, radiating from the water-parting of a 

 country, must necessarily result from the descent of the streams from the 

 mountain crests to the sea. He discerned that this ceaseless and wide- 

 spread decay would eventually lead to the entire demolition of the dry 

 land, but he contended that from time to time this catastrophe is pre- 

 vented by the operation of the underground forces, whereby new 

 continents are upheaved from the bed of the ocean. And thus in his 

 system a due proportion is maintained between land and water, and the 

 condition of the earth as a habitable globe is preserved. 



A theory of the earth so simple in outline, so bold in conception, so 

 full of suggestion, and resting on so broad a base of observation and 

 reflection, ought, we might think, to have commanded at once the atten- 

 tion of men of science, even if it did not immediately awaken the interest 

 of the outside world ; but, as Playfair sorrowfully admitted, it attracted 

 notice only very slowly, and several years elapsed before anyone showed 

 himself publicly concerned about it, either as an enemy or a friend. 

 Some of its earliest critics assailed it for what they asserted to be its 

 irreligious tendency — an accusation which Hutton repudiated with much 

 warmth. The sneer levelled by Cowper a few years earlier at all inquiries 



