In considering this subject we will suppose the commencement of the canal somewhere near the out-let of Lake Erie. The inducements for preferring one market to another, involve a variety of considerations; the principal are the cheapness and facility of transportation, and the goodness of the market. If a cultivator or manufacturer can convey his commodities with the same ease and expedition to New-York, and obtain higher price for them than at Montreal or New-Orleans, and at the same time supply himself at a cheaper rate with such articles as he may want in return, he will undoubtedly prefer New-York. It ought also to be distinctly understood, that a difference in price may be equalized by a difference in the expense of conveyance, and that the vicinity of the market is at all times a consideration of great importance. From Buffalo, at or near the supposed commencement of the canal, it is 450 miles to the city of New-York, and from that city to the ocean, 20 miles. From Buffalo to Montreal 350 miles; from Montreal to the Chops of the St Lawrence 450. From Buffalo to New Orleans by the great Lakes, and the Illinois river, 2,250 miles; from New-Orleans to the Gulf of Mexico 100. Hence, the distance from Buffalo to the ocean by the way of New-York is 470 miles; by Montreal 800; and by New-Orleans 2,350. As the upper lakes have no important outlet but into lake Erie, we are warranted in saying, that all their trade must be auxiliary to its trade, and that a favorable communication by water from Buffalo, will render New-York the great depot and warehouse of the western world. In order, however, to obviate all objections that may be raised against the place of comparison, let us take three other positions, _Chicago_ near the southwest end of lake Michigan, and a creek of that name, which sometimes communicates with the Illinois, the nearest river from the lakes to the Mississippi; _Detroit_, on the river of that name, between lakes St Clair and Erie; and _Pittsburgh_, at the confluence of the Alleghany and Monongahela rivers, forming the head of the Ohio and communicating with Le Beuf by water, which is distant fifteen miles from lake Erie. The distance from Chicago to the ocean by New-York, is about 1200 miles. To the mouth of the Mississippi, by New-Orleans, near 1600 miles, and to the mouth of the St Lawrence, by Montreal, near 1600 miles. The distance from Detroit to the ocean by New-York, is near 700 miles. From Detroit to the ocean by Montreal, is 1050 miles. From Detroit to the ocean, pursuing the nearest route by Cleveland, and down the Muskingum, 2400 miles. The distance from Pittsburgh to the ocean, by Le Beuf, lake, Buffalo, and New York, is 700 miles. The same to the ocean by Buffalo and Montreal, 1050 miles. The same to the ocean by the Ohio and Mississippi, 2150 miles.