CH. XXXI. SU'JMAAY. 293 



floors, and the carpets which cover them ! All these have 

 been woven, and forged, tempered, sawn, and worked by 

 steam machinery. Then think of the way in which people 

 are carried from one place to another of the world ; so that 

 in one month a man may be in India, and the next in 

 London ; while food, clothing, and goods of all kinds are 

 spread over different countries in a few weeks wherever they 

 are most wanted. And then remember that all this has 

 sprung out of the latent heat of steam, and its application 

 by Watt to the steam-engine. 



The next discovery is perhaps even more wonderful. 

 Franklin tries experiments upon the peculiar power known 

 by the name of electricity, and he suspects that it is every- 

 where and in everything. He proves its transmission from 

 one body to another, and finds out many of its properties. 

 In spite of the derision of his friends, he seeks to bring it 

 down from the sky, and succeeds in making a prisoner of 

 the lightning and working with it in his own laboratory. 

 Galvani next finds this wonderful power hidden in the nerves 

 of a frog ; while Volta crowns the whole by showing that 

 electricity can be produced by two metals placed in a little 

 acid and water, and that this can be carried along a wire of 

 any length which touches the battery at both its ends. 

 Here lies hid the germ of the electric telegraph ; but the 

 grand secret of carrying messages from one end of the 

 world to another in a few moments was not to come yet. 

 That remained for the nineteenth century to accomplish. 



Astronomy. Lastly we come to astronomy, and to 

 some of the most tremendous problems in the working of 

 our universe. Here we find Lagrange proving that the 

 system of our sun and planets is self-regulating, so that in 

 spite of all its infinite changes there is no real irregularity 

 or changeableness in its machinery, but all moves in one 



