SCIENTIFIC TRACTS. 



NUMBER XXIII. 



RAIL-ROADS. 



THE most simple inventions have been among the most 

 important, though they soon became common and ceased 

 to attract notice. 



The cord and pulley must have caused an improve- 

 ment upon mere brute force, as astonishing in its day as 

 its multiplied action in spinning machinery has been sur- 

 prising in our time ; then it was that man could act where 

 he was not. 



The wheel itself now so simple, so component a part 

 of daily action, was once an invention of no ordinary 

 mind. 



The cask or common hogshead was an immense stride 

 in commercial facilities. By this, a man readily conveys 

 over a level space, a ton weight, which would otherwise 

 require twenty men to move, and on a slight inclination, 

 he commands a self-acting power attainable in no other 

 mode but by machinery. 



In the history of locomotion there is much of this sim- 

 ple invention, less noticed than its value demands. If 

 there is anything that distinguishes one people from 

 another, it is, eminently, the power of intercommunica- 

 tion, and yet in principle how simple the means. 



COMPARED WITH CANALS. 



The knowledge and use of canals appear to have been 

 of long standing. The ancients (though ignorant of 

 locks,) were familiar with the simple canal or cut on one 



VOL. i. NO. xxin. 49 



