26 Mr G. R. Blackwell on the Volume of the Niagara Eiver. 



When it is considered that the water-power of the cataract 

 of Niagara is unceasing, by night as well as by day, and that 

 the power, as calculated above, for practical purposes in Great 

 Britain, is only applied, on an average, about eleven hours per 

 day, during six days of the week, it may be assumed that the 

 motive-power of Niagara Falls is at least forty-fold of the 

 aggregate of all the water and steam power employed in 

 Great Britain, and probably equal to the aggregate of all the 

 motive power employed for mechanical purposes on this earth. 



The surface of Lake Erie is found to be 331 feet above the 

 surface of Lake Ontario, and 565 feet above that of the 

 ocean. The descent of the waters of Niagara River, in the 

 few miles of distance between Black Rock and Queenston, is 

 about 171 feet, exclusive of the grand cataract itself, forming 

 a succession of rapids, which, in some places, present to view 

 the sublime spectacle of the agitated surface of the ocean in 

 a storm ; and these rapids continue to occur during the sub- 

 sequent descent of the river St Lawrence, from the level of 

 Lake Ontario to that of the sea, making, in the aggregate, 

 above three-fold of the waterfall of the grand cataract, and, 

 consequently, one hundred and twenty-fold of all the physical 

 power derived from the use of all the waterfalls and steam- 

 engines employed, as above stated, in Great Britain, omitting 

 to take into account the several huge rivers that are tribu- 

 taries of the St Lawrence. Such, and in so great a scale, are 

 |he ordinary operations of the impulses of physical power em- 

 ployed in the " mechanics of nature," in governing the move- 

 ments of the waters of a single river, exceeding manyfold the 

 portion of physical forces rendered available and employed 

 by all the inhabitants of the earth, as a motive-power in the 

 *' mechanics of the arts." There is thus furnished an im- 

 pressive lesson to humble the pride of man in his boasted 

 achievements of the triumphs of mind over inert matter. It 

 is well that these considerations should occur to the spectator, 

 whilst he regards the cataract of Niagara ; for nowhere is 

 there exhibited on this earth a more impressive spectacle of 

 the display of energetic physical power. Cold and indifferent, 

 indeed, to the highest attribute of Omnipotent excellence, 

 must be the mind of that human being, who can raise his eyes 



