Canal, an artificial water-course. Canals are used principally for navigation, but also for drainage, for irrigation and for supplying cities and towns with water.
Navigation canals are of two kinds: (a) ordinary canals which are only a few feet deep and are traversed principally by special canal boats and barges, and (b) ship canals which admit sea-going vessels. A canal must be built in a series of level stretches. Where a change of level is made, the boats are generally raised by means of locks, but sometimes by lifts and cars. Canals for inland navigation have been used for many centuries. The Grand Canal of China was built in the 8th century, is 650 miles long and is still in use. Canal systems in Europe are very extensive. In Russia the system of canals was started by Peter the Great, and St. Petersburg is connected with the Caspian and Black Seas. Sweden has 800 miles of canals. Both Germany and Austria have their principal rivers connected by canals, and Austria has recently planned a large increase of its canals. The canals of Holland are almost the roads of the country. In Great Britain there are about 5,000 miles of navigable canals, so that every town in the island is within a few miles of navigable water. The first canal in the United States was built in 1793 around the falls of the Connecticut River at South Hadley, Mass. In the early part of the 19th century a very extended system of canals was planned, but of the 5,000 miles planned, less than 3,000 miles were constructed, and many of these have since been abandoned. This is due to the building of railroads and the great reduction in the cost of overland transportation in recent years, owing to improvements in railroad service. Most engineers are agreed that the ordinary canal can never be made to compete with the railroads in the United States. Now, however, the tremendous growth of the country's commerce has made it absolutely indispensable to improve all our waterways and make new canals. The railroads cannot carry the freight. An unofficial inland waterways commission appointed by the government in March, 1907, has made a careful study of the rivers and canals of the whole country. In May, 1908, the governors of all the states in the Union, together with private delegates from every state, conferred on the subject at Washington with the national government, and Congress is considering a bill to create an official inland waterways commission. Several of the canals built in the early part of the century are noteworthy on account of the effect they have had on trade relations. The principal of these canals is the Erie Canal, built by the state of New York and opened in 1825. It extends from Buffalo to Albany, a distance of 352 miles. Originally it was but four feet deep, but it has been widened and deepened at great cost to the state, so that it now can accommodate boats drawing seven feet. The traffic on the canal is not, however, satisfactory, and propositions are being urged to make it a ship canal. Other notable canals are the Chesapeake and Delaware Canal (1824-29) and the Delaware and Raritan Canal (1831-34), which connect the cities of New York, Philadelphia and Baltimore.
Ship-canals are built to connect two bodies of water so as to shorten routes. The most notable of these canals is the Suez Canal connecting the Mediterranean and Red Seas. It was opened in 1869 and reduced the distance of water transportation between Europe and India from over 11,000 miles to about 7,500 miles, and caused a saving of 36 days in the journey. The canal is about 100 miles long, and had originally a depth of 26 feet and a width at bottom of 72 feet. The depth has been increased to 28 feet and the width to over 200 feet, so as to accommodate the enormous traffic. The total cost of the canal, including the approaches at both ends, is said to have been $100,000,000. Other notable ship canals are the Caledonian Canal (a minor ship canal), the Corinth Canal, the Kiel Canal, opened in 1895, 63⅓ miles long and connecting the Baltic and North Seas, the Manchester Ship Canal, the Panama Canal now under construction to connect the Atlantic and Pacific Oceans and the Welland, Huron and “Soo” Canals, the last of which has more traffic in seven months than the Suez Canal in a year.
Drainage-canals are for the purpose of carrying off the sewerage of cities. The most notable of these canals is the Chicago drainage canal connecting the Chicago River with the Illinois River by the way of the Desplaines River. The current in the Chicago River is thus turned backward and 300,000 cubic feet per minute are thus taken from Lake Michigan and reach finally the Mississippi River instead of the St. Lawrence. The cost of the work has been over $63,000,000, and owing to the effect of the current on navigation in the Chicago River, a large additional sum will have to be expended to enlarge the river channel to provide an additional inlet. It has been in the plans of the construction of this canal to make it a ship-canal, so as to connect Chicago with the Gulf of Mexico for large vessels, and as engineers who have studied the problems and prepared plans pronounce the project feasible, and the entire country is entering on an era of building canals and improving waterways, it is not improbable that this will be done.