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gethef a fccnery fomewhat like enchantment, 

 and exhibit at once a view that mud give 

 you an idea of prodigious labour ; for the 

 can a) is here not only carried over the Ir- 

 welij but likewife acrofs a large valley, be- 

 ing banked up on each iide in a furprizing 

 manner, to form a mound for the water, 

 and the channel alfo filled up to the ufual 

 depth, that the banks, at a place where they 

 are entirely artificial, and confequently weak- 

 er than where natural, might not be endan- 

 gered by the great preflure of lb large a body 

 of water as the depth here filled up would 

 have contained : And I mould remark, that 

 it is a maxim throughout this whole navi- 

 gation, to keep the canal every where of an 

 equal depth. I believe it fcarce ever varies 

 above fix inches -, from four feet, to four 

 feet fix inches. 



The method Mr. BrintUey takes to fill up 

 a channel, where too deep, is a molt admi- 

 rable one : He builds two very long boats, 

 fixes them within two feet of each other, 

 and then erects upon them a triangular 

 trough, large enough to contain feventeen 

 tons of earth : The bottom of this trough 

 is a line of trap-doors, which, upon draw- 

 ing a pin, fly open at once, and difcharge 

 the whole burthen in an inftant. Thefe 

 boats are filled any where from the banks 

 wher : earth is in fuperfluous quantities, 

 irrowing hi on a plank, laid from 



the 



