the top varying from 162 to 290 feet. The canal extends from the Chicago River in Chicago to Lockport, where it joins the Des Plaines River. It has been proposed to deepen this canal and also the Illinois and Mississippi rivers and construct locks so that barges and light-draught vessels could pass direct from the Great Lakes to the Gulf of Mexico.
Besides the Erie and the Illinois and Michigan, the other large canals of the United States are the Delaware and Hudson (now in disuse), at one time the great coal route to New York from the Pennsylvania mines, 108 miles long, completed in 1820, cost $6,300,000; the Chesapeake and Ohio, 185 miles, cost $11,375,000; the Schuylkill Coal and Navigation Company's Canal, 108 miles, cost $13,207,000; and the Wabash and Erie in Indiana, 274 miles, cost $6,000,000. There are 13 canals in New York, 14 in Pennsylvania, 5 in Ohio, 4 in Virginia, 2 in New Jersey, and 1 each in Delaware, Maryland, Indiana, Illinois, and Michigan. The Chesapeake and Ohio Canal originated in a project formed by Washington as early as 1774, to make the Potomac navigable from tidewater to Cumberland, and to connect it by common roads and portages with the affluents of the Ohio west of the Alleghanies. The War of the Revolution postponed the scheme, but in 1784 it was again broached by Washington, and Maryland and Virginia appointed a joint commission, with him at the head, to investigate the subject. The result was the incorporation of a company to make the Potomac navigable from the tidewater to the highest possible point by the construction of such locks as might be necessary for that purpose. Of this company, Washington was the president until his election as President of the United States compelled his resignation. The project encountered many obstacles, until at last, in 1820, it was abandoned as impracticable; when the Board of Public Works of the State of Virginia took steps which led to the organization of a new company, which constructed the Chesapeake and Ohio Canal from Georgetown to Cumberland, completing it in 1850. It passes through the Potomac Valley to Paw Paw Bend, from which point it passes through the mountains by a tunnel 3118 feet long. The whole length of the canal is 184 miles, its depth 6 feet, its width to Harper's Ferry, 60 feet at the surface and 42 feet at the bottom. By means of 74 locks 100 feet long and 15 feet wide, an elevation of 609 feet is gained. All the water is supplied from the Potomac. At Georgetown the canal was led over the Potomac by means of a great wooden aqueduct bridge. The cost of the work was over $11,000,000. The Morris Canal connects the Delaware at Phillipsburg, N. J., with the Hudson at Jersey City. It is 102 miles long and accommodates vessels of 80 tons. An interesting feature of this canal is the use of inclines for connecting the different levels; there are 23 of these inclines, with an average rise of 58 feet.
The only boat canal, strictly speaking, which has been constructed in the United States since 1850 is the Illinois and Mississippi Canal, now under construction in Illinois. This canal is designed as a short route from the upper Mississippi River to Lake Michigan in connection with the existing water routes of Illinois. It extends from Hennepin, Ill., to Rock Island, Ill., 77 miles, of which 50 miles are canal and 27 miles are slack water navigation down the Rock River. The canal proper and the summit-level feeder will be 7 feet deep and 80 feet wide at water-level. The feeder will be 34.75 miles long. There will be 37 concrete locks, 35 × 70 feet, with lifts of from 3 feet to 10 feet. Construction was begun in July, 1892, and in 1902 was in progress.
The Canadian canal system is one of the most important in the world, and comprises the Saint Lawrence and Lake Navigation, the Ottawa and Rideau Navigation, the Richelieu and Champlain Navigation, and the River Trent Navigation. Of these, the Saint Lawrence system is the most important, as it gives a 14-foot waterway from the head of Lake Superior to the Gulf of Saint Lawrence. The canals of the Saint Lawrence system are the following:
| NAME OF CANAL | Length, Miles |
Number of Locks |
Lockage, Feet |
Dist. from Prec. Canal |
| St. Mary's | 0.66 | 1 | 18. | |
| Welland | 26.75 | 25 | 362.75 | 600 miles |
| Galops | 7.625 | 3 | 15.5 | 226 miles |
| Rapids Plat | 4. | 2 | 11.5 | 4.5 “ |
| Farrens Point | 0.75 | 1 | 4. | 10.5 “ |
| Cornwall | 11.5 | 6 | 48. | 5. “ |
| Soulanges | 14. | 4 | 82.5 | 32.75“ |
| Lachine | 8.5 | 5 | 45. | 15.25“ |
Ship Canals. Examples.—In the last half of the Nineteenth Century, with the development of steam navigation and maritime trade, a demand arose for the construction of canals of large dimensions across isthmuses to shorten the route by sea between certain countries, to connect important internal manufacturing and commercial cities with the ocean, or to afford communication between bodies of water in the interior of a continent. Among the more notable examples of such ship canals are the Suez, Corinth, Manchester, Saint Mary's, Saint Petersburg and Kronstadt, Baltic, and Amsterdam. The Suez Canal (q.v.) cuts through the Isthmus of Suez and connects the Mediterranean with the Red Sea. It is about 100 miles long, has a bottom width of 72 feet, and a depth of 26 feet, and was built 1860-69. The Manchester Canal runs from the Mersey at Eastham just above Liverpool, to Manchester, is 35.5 miles long, 26 feet deep, and has a minimum bottom width of 120 feet. It is built in four reaches connected by three sets of docks at Latchford, Islam, and Barton, the sizes of the locks of each set being 550 × 60 feet, 300 × 40 feet, and 100 × 20 feet. One of the notable structures of this canal, and the only one of its kind, is a swing aqueduct by which the Bridgewater Canal is carried over the Manchester Canal. This aqueduct opens exactly like a swing-span drawbridge to permit vessels with masts to pass through. The Corinth Canal is another of the trans-isthmian type, crossing the Isthmus of Corinth with a cut 4 miles long, 72 feet wide, and 26.5 feet deep. This canal was completed in 1893. It is stated that this canal was projected by Alexander the Great, determined upon by Julius Cæsar, and actually begun by Nero, though the work never progressed beyond a few hundred yards.
The Saint Mary's Canal, commonly known as the Sault Sainte Marie Canal, connecting the waters of Lake Superior with those of the Saint Mary's River and Lake Huron around the Saint Mary's Falls in Michigan, is but a few thousand
