WATER STEAM. 77 



riations are trifling, and not necessary to be taken 

 into account in common observation, though we 

 cannot observe even the operations of nature to 

 proper advantage, without knowing something of 

 their causes. 



When the water comes to the boiling point, if 

 the surface of it is freely exposed to the air, it 

 never becomes any hotter ; and after it fairly boils, 

 one could not warm it one jot, except it were in 

 a closed vesselj even though it were exposed to a 

 fire of the greatest strength for twelve months. 

 And the water contends for this law of its being, 

 eVen when it is in small quantity, with strength 

 far exceeding the strength of armies. It is the 

 resistance of water to being heated above the boil- 

 ing point, which has enabled England to add the 

 steam engine to the implements of her labour; 

 and thus leave the horses to the plough and the 

 team, and man to superintend and to observe, and 

 thence to learn and to do, more and more for his 

 own enjoyment, and the improvement of his coun- 

 try and his kind. The people who lived two cen- 

 turies ago, and who were as wise and observant 

 in their generation as we are, would have thought 

 the teller mad if they had been told, that inde- 

 pendently of their downward motion to the sea, 

 which turns the mill and carries the barge as they 

 glide, there slumbers in the streams an active 

 power a source of motion, not only greater than 

 that of all the men and all the horses and other 

 animals in England, but greater than the expertest 

 penman in the world could set down by arith- 

 metical contrivance, though he sat cyphering his 

 whole life. And the beauty of the matter is, that 

 this mighty power, which is in the possession of 

 H 3 



