OF THE RIVER SAINT LAWRENCE. 



287 



the barrier which separates, and maintains the difference of level between Lake Eric and 

 Lake Ontario, the natural discharge of the former being by Niagara River and Cataract. 



The work consists of a reach of canal extending from Lake Erie to the head of a series 

 of lockages overcoming a lift of three hundred and thirty-one feet, which, as shown in the 

 section, are grouped rather closely together on the rapid descent through the villages of 

 Thorold, St. Catharine's, and Port Dalhousie. The entire length of the canal is twenty- 

 eight miles, in addition to which there is a feeder of twenty-one miles in length, derived 

 from the Grand River, which is dammed up to the extent of seven feet, for the purpose 

 of affording a steady supply of water, as well as of avoiding an expensive difficulty in con- 

 struction by extending the depth of the excavation, which has been a constant source of 

 trouble, but it was, perhaps, the more desirable, in consequence of the extreme fluctua- 

 tions which take place in the level of Lake Erie. The chief work upon this canal is the 

 Summit Level Cutting, cut through the Niagara limestone, which has caused very con- 

 siderable difficulty by slips and slides. The locks, twenty-four in number, are one hundred 

 and fifty feet long, twenty-six feet six inches wide, and vary from fourteen feet to nine 

 feet lift. The capabilities of the canal admit of vessels one hundred and forty-two feet 

 long, twenty-six feet beam, and ten feet draft. There is also a work connected with this, 

 called the Welland Feeder, extending to Dunville, and the Broad Creek Branch, con- 

 necting the last-named feeder with Port Maitland. The Welland Feeder lias the same 

 width at top and bottom as the main canal, viz., seventy-one feet at top, and thirty-five feet 

 at bottom, and has eight feet depth ; while the Broad Creek Branch has ten feet depth, and 

 in width is eighty-five and forty-five feet respectively at top and bottom. The locks are 

 built of stone, and the whole work, which is under the able control and management of 

 the Hon. II. II. Killaly, Commissioner of Public Works, has received every attention and 

 appliance for facilitating and economizing the transit of the very heavy traffic of which it 



is the medium. 



The Lachine Canal, as before described, was started in the year 1819, upon the limited 

 width described, but in the year 1833, after the fullest attention given to the subject by 

 the Provincial Government, a new system was begun, which proposed to construct works 

 up the line of the St. Lawrence, capable of passing sea-going vessels, and large steamers, 

 suited to the navigation of the upper lakes. And the important works which followed, 

 including the reconstruction of the Lachine Canal, are quite worthy of the age in an 

 engineering point of view. 



The Lachine Canal has been widened and deepened, to one hundred and twenty feet 

 width at top, eighty feet at bottom, and ten feet in depth. The terminal points, and the 

 length (which is eight and a half miles) are the same. The locks, which are four in 



