j8 On Canals. 



ing the mnmifatlured good^ from thence, or for carrying tlie 



Eroduce of mines to the fea-fliores, — the line of canal Ihould 

 e made in as fliort a diredlion as the nature of the country 

 w»Il admit of, even if this Hne lliould be atttended with fome 

 extraordinary expenfe ; and that mode of conveyance fliould 

 lie adopted which is lead Hable to be interrupted, becaufe in 

 thofe cafes much depends upon aconftant and regular fupply. 

 If the canal is chiefly for the purpofes of agriculture, thofe 

 lines are to be fought for which will accommodate the country 

 moft perfciSlly at the leall poffible expenfe. This will not, 

 in general, be effected by fhort and direft, but, on the con- 

 trary, by circuitous and level lines, fuch as will vifit many 

 parts of the country, carry fuel and manure into every quar- 

 ter, and take oif the produce of the land for back carriage. 

 Merchandize, although a very inferior confideration, will, oy 

 the fame means, be extenfively and equally diftributed. When 

 the carriage of thofe heavy but neceflary articles is rendered 

 cheap, and the fupply convenient, the confumption will in- 

 ereale. '1 he very ufe of lime as a manure is in general fuf- 

 ficient to create a confiderable revenue upon a canal, when 

 the coal and limeftone can be carried along the canal at a 

 moderate expenfe. As improvements in agriculture muft in- 

 crcafe the wealth of the inhabitants, more articles are required 

 to fupply their multiplied wants ; the pofl'eflion of capital 

 prompts them to enter upon new employments, and the de- 

 mands of all create an addition of bulinefs upon the canal. 



Many other advantages attend circuitous aqd level canals. 

 If there are upland countries above the level of the canal, 

 fome cheap and convenient fituations may be fele<Sed where 

 the wafte water of the uplands can be colle<9;ed info refervoirs 

 to be formed for this purpofe. From thofe refervoirs the water 

 may be taken into the canals. At various points of the ca- 

 nal, where there are falls immediately on the lower fide, mills 

 may be eretSled for grinding corn, or for the purpofes of ma- 

 nufadures: in many parts, two or three overfhot wheels, of 

 lufficient diameter, may be placed below each other : when 

 the water has performed thofe ufcful offices, it will fall into 

 the brooks, and prove a plentiful and regular fupply to other 

 works in the courfe of each Itream. 



Improvemcnls in agriculture may alfo be greatly promoted 

 by ufing^a part of the wafte water for the purpofe of irriga- 

 tion. For a canal carried over a country upon a high level 

 would prove an extenfive top drain. Not only the land ad- 

 joining the banks of the canal, but ail which lies below the 

 level, may enjoy the ufe of the water for irrigation ; and the 

 brooks and rivers will be the tail drains of the country. 



CoHefiting 



