HUTTON. 233 



Most unfairly was Hutton attacked, and he was 

 thus defended by his friend Playfair : " In the 

 planetary motions, where geometry has carried the 

 eye so far, both into the future and the past, we 

 discover no mark either of the commencement or 

 termination of the present order. It is unrea- 

 sonable, indeed, to suppose that such marks should 

 anywhere exist. The Author of nature has not 

 given laws to the universe, which, like the constitu- 

 tions of men, carry in themselves the elements of 

 their own destruction. He has not permitted in 

 his works any symptom of infancy or of old age, 

 or any sign by which we may estimate either their 

 future or their past duration. He may put an end, 

 as He no doubt gave a beginning, to the present 

 system at some determinate period of time ; but 

 we may rest assured that this great catastrophe 

 will not be brought about by the laws now ex- 

 isting, and that it will not be indicated by anything 

 which we perceive." 



Hutton studied meteorology, and gave to the 

 world the first reasonable theory of the cause of 

 rain. He described the formation of invisible 

 vapour by evaporation, the production of visible 

 mist and cloud, and finally rain. And he investi- 

 gated the reasons of the cause of rainfalls differing 

 in amount in the tropics and temperate zones of 

 the earth. In 1793 serious illness attacked Hutton 

 after he had been writing his speculations regard- 

 ing matter. On his recovery he republished his 

 work on the " Theory of the Earth," and replied 



