Canals.

River St. Lawrence and Lakes.

The St. Lawrence navigation extends from the Straits of Belle-Isle to the head of Lake Superior, 2, 84 miles This lake is 60 feet above the highest tidal flow of the St Lawrence. The first interruption in the navigation occurs at Montreal, 386 miles from Belle-Isle, in the St. Louis Rapids. The Lachine Canal around these rapids is 8½ miles long. Very extensive new works are rapidly approaching completion on this canal These form new entrances at Montreal and Lachine duplicating the locks, give a channel between the harbour of Montreal and Point st. Charles, for vessels drawing 18 feet of water, and all the way to Lachine for vessels drawing 12 feet. The navigation was only once interrupted during the season of 1877, and then only for 24 hours. 15¼ miles from the head of the Lachine Canal, on the south side of the river, the Beauharnois Canal avoids the three rapids of the "Cascades,' "Cedars" and "Cotean" The navigable season on this canal in 1877 was 209 days, and no interruption of any kind occurred, though a great main repairs were made. Above the Beauharnois Canal, lake st. Francis, a widening of the St. Lawrence, is navigable for 32¼ miles. Here the Cornwall Canal, 11½ miles long is constructed around the Long Sault Rapids. This Canal is being enlarged and improved. There was no interruption to navigation, five miles from the head of the Cornwall Canal commence 3 short canals known as the Williamsburg Canals. Two of these Farran's Point, ¾ of a mile long, and the Rapid Flat, 4 miles long, are only used by vessels ascending the river, the rapids offering no difficulties to vessels in the descent of the river. The distance between the two is 10½ miles; 4½ miles further up is the third of the Williamsburg Canals, 7? miles long. Beyond this the navigation is uninterrupted to Port Dalhousie at the head of Lake Ontario, 229 miles Here the Welland Canal, over 27 miles long, passes between Lakes Erie and Ontario. When the new works on this Canal are completed, a navigation will be established 26 27 miles long, 25 feet deep, with a breadth of 100 feet at bottom, with 24 locks 270 feet long, 45 wide and 14 feet deep on the sills The mean difference of level between the two lakes has been determined at 326¾ feet. The basin at the harbour of Port Dalhousie will extend over 10 acres, with a depth of 16 or 17 feet. At Sault St. Marie, between Lakes Huron and Superior, 623 miles from the Lake Erie entrance of the Welland Canal, the United States Government have constructed a canal, a mile in length, 18 feet lockage and 16 feet on the sills, to avoid the St. Mary Rapid. The distance from this point to the head of Lake Superior is 397 miles, giving, in the total St. Lawrence navigation 2,312¼ miles open navigation, and 7131 miles canal: 2,234 statute miles. At the western end of Lake Ontario, a small anal, half a mile long is cut through the sand bar separating Burlington Bay from the Lake, and gives access to the Port of Hamilton.