THE ASTRONOMICAL VIEW OF NATURE. 303 



of the pioneers of science. One of these benefits, and 

 perhaps that which to an external beholder marks the 

 greatest difference between the first and the second half 

 of the century, is the greatly increased intercourse which 

 now exists as compared with the earlier years of our cen- 

 tury. This intercourse has reacted on the domain of 2. 



Science be- 

 thought, and produced that exchange of ideas which come inter- 

 national. 



promotes more rapid progress. It hardly belongs to the 

 history of thought to analyse 1 the different steps by which 

 the great change has been brought about. Still, a very 

 superficial glance will suffice to show how the work of 

 bringing about an international exchange of ideas has 

 been very characteristically divided among the three 

 nations in which we are specially interested. It was not 

 in the interest of thought, of science, or of literature, but 

 rather in that of commerce and of industry, that the 

 modern facilities of intercourse and exchange were in- 

 vented and introduced. 2 We shall therefore expect to 



1 The principal dates of the in- [ 1835. The first German railway 

 troduction of steam - engines and was opened between Niirenberg and 

 telegraphs for facilitating communi- Fiirth. The first electric telegraphs 

 cation are as follows : for public use were almost simul- 



1802. The tug Charlotte Dundas, taneously constructed in England, 

 built by Symington, was tried on Germany, and the United States 



the Forth and Clyde Canal. ' the first successful line being prob- 



1812. Henry Bell built the Comet ably that constructed by Wheat- 

 with side paddle-wheels. It ran on stone and Cooke between 1836 and 

 the Clyde as a passenger steamer. 1840. The first Atlantic cable was 



1829. George Stephenson's Rocket begun in 1857, and after repeated 

 was tried on the Stockton and Dar- failures, which were in the main 

 lington Railroad, which had been corrected by the scientific investi- 

 begun in 1821. In the year 1829 gations of William Thomson (Lord 



the Liverpool and Manchester Rail- . Kelvin), telegraphic communication 



way was inaugurated. | with America was permanently es- 



1838. The first steamboats, Sirius tablished in 1 8 6 6 . 



and Great Western, crossed the 

 Atlantic. 



2 This remark applies fully to the 

 railway system, but scarcely to the 



1833. A comprehensive system of development of the electric tele- 

 railways was planned by the French graph, which was first actually used 

 and Belgian Governments. for scientific purposes by Gauss and 



