288 



ON THE HYDROLOGY OF THE BASIN 



number, are forty-two feet three inches wide at the lower level, and forty-five feet across 

 at the top-water surface. The maximum lift is thirteen feet, the minimum eight and 

 three-quarters feet. Vessels of one hundred and eighty-five feet length, forty-four feet 

 beam, and nine feet draft, are the limits of capacity. 



The navigation from the head of the Lachine Canal upwards passes through Lake 

 St. Louis, and crosses over to the southeast side near the upper end of the lake, to 

 enter the Beauharnois Canal, which is the next work. It connects Lake St. Francis with 

 that of St. Louis, at the foot of the Cascade Rapid, and this canal avoids also the Cedars 

 and Coteau Rapids. The length of the canal is eleven and three-quarters miles. Its width 

 at top-water is the same as that of Lachine. The locks are nine in number, two hundred 

 feet long, forty-five broad at top-water, forty-three and a half feet at the lower water sur- 

 face. The greatest lift is eleven feet, the least eight feet, and the same class of vessels 

 navigate it as pass the Lachine Canal; it is the only canal which takes the south side of 

 the river, — the mean distance from the American frontier is twenty-five miles. 



Passing up stream through Lake St. Francis, we arrive, at a distance of sixty-three 

 miles from Montreal, at the foot of the Cornwall Canal, which is eleven and a half miles 

 long, and surmounts the Long Sault Rapid, which has a total fall of forty-eight feet. 

 The width of the canal is one hundred and fifty feet at top and one hundred feet at bot- 

 tom, with a depth of ten feet. It is principally formed by reclaiming out of the space 

 originally occupied by the river and its bank, sufficient space for the formation of the cross 

 section described. 



It may be as well to remark that the centre of the river from this point onwards, is the 

 dividing line between Canada and the United States, the line of forty-five degrees north 

 latitude striking the River St. Lawrence at St. Regis, a short distance below the lower 

 end of this canal. And it is interesting to observe the small width of the river near this 

 point, as shown on an enlarged plan, and that the narrowest width between United 

 States territory and the Canadian shore is about six hundred feet, measured between the 

 northwestern side of Croiles Island and the canal bank. The locks on this canal are two 

 hundred feet long, fifty-five feet on the top of the walls, and fifty-three and a half feet at 

 the lower level. 



The Williamsburg Canal, consisting of four short canals, the last of these so-called St. 

 Lawrence Canals, commences at eighty-nine and a half miles above Montreal, and was 

 constructed to avoid the Farren's Point, Rapid Plat, Point Iroquois, and Galops Rapids, 

 which have a total fall of twenty-nine and a half feet. With the construction of these 

 canals was completed, in 1847, the last link of this great inland system. Their aggregate 

 length is nine and three-quarters miles ; their cross section is ninety feet top, fifty feet 

 bottom, and ten feet deep. There are six locks two hundred feet long, forty-five feet wide 



