Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/865

Rh CANAL 783 the 14th century the introduction of locks, whether of Dutch or Italian origin, gave a new character to inland navigation, and laid the basis of its rapid and successful extension. And here it may be proper to remark, that the early canals of China and Egypt, although destitute of locks, do not appear to have been on that account formed on a uniformly level line, unadapted to varying heights. It is very doubtful, indeed, if the use of locks has even yet been introduced into China, intersected as it is by many canals of great antiquity and extent, the imperial canal being about 1000 miles in length. &quot; This canal appears to have been completed in 1289, and is said to extend fora distance of forty days navigation, and is provided with many sluices, and when vessels arrive at these sluices they are hoisted by means of machinery, whatever be their size, and let down on the other side into the water.&quot; 1 Nevertheless the invention of locks was, as has been stated, a most important step in the history of canals ; and that mode of surmounting elevations may be said to be almost universally adopted throughout Europe and America. Inclined planes and perpendicular lifts have, it is true, been employed in those countries, as will be noticed hereafter ; but the instances of their application are undoubtedly rare. mguedoc But without tracing the gradual introduction of canals au & from country to country, we remark at once that we find the French at the end of the 17th century, in the reign of Louis XIV., forming the Languedoc Canal, designed by Riquet, between the Bay of Biscay and the Mediterranean, a gigantic work, which was finished in 1681. It is 148 miles in length, and the summit level is GOO feet above the sea, while the works on its line embrace upwards of one hundred locks and fifty aqueducts, an undertaking which is a lasting monument of the skill and enterprise of its projectors ; and with this work as a model it seems strange that Britain should not, till nearly a century after its Execution, have been engaged in vigorously following so laudable an example. This seems the more extraordinary, as the Romans in early times had executed works in England, which, whatever might have been their original use, whether for the purposes of navigation or drainage, were ultimately, and that even at an early period, converted into navigable canals. Of these works we particularly specify the Caer Dyke and Foss Dyke cuts in Lincoln shire, which are by general consent admitted to have been of Roman origin. The former extends from Peter borough to the River Witham near the city of Lincoln, a distance of about 40 miles ; and the latter extends from Lincoln to the River Trent, near Torksey, a distance of 11 miles. Dyke. Of the Caer Dyke the name only now remains ; but the Foss Dyke, though of Roman origin, still exists, and as it is the oldest British canal, the reader may be interested to learn the following facts as to its history. Camden in his Britannia, states that the Foss Dyke was a cut originally made by the Romans, probably for water supply or drainage, and that it was deepened and rendered in some measure navigable in the year 1121 by Henry I. In 17G2 it was reported on by Smeaton and Grundy, who found the depth at that time to be about 2 feet 8 inches. 2 They, however, discouraged the idea of deepening by excavation. They say they .found &quot; the bottom to be either a rotten peat earth, or else a running sand,&quot; and that though the deepening of the navigation is in &quot; nature possible,&quot; yet it cannot be effected without removing one of the banks in order to widen the same,&quot; which would not only turn out expensive, but would &quot;occasion much loss of time and profit to the proprietor while the work is executing.&quot; Nothing 1 Travels of Marco Polo, by Col. Yule, C.B. 2 Smeivton s Reports, vol. i. p. 55, London, 1812. followed on this report; but in 1782 Smeaton was again called in, and deepened the navigation to 3 feet 6 inches, not, however, by widening the canal or dredging, but by raising the water-level 10 inches. 3 From that period nothing more was done to enlarge the water-way, or adapt it to increased traffic. Meantime the adjoining Witham navigation having been improved, the defects of old Foss became more apparent, and in 1838 Mr Vignoles was consulted, and made an elaborate report on alternative schemes for increasing the depth to 4 and 6 feet ; nothing, however, was done till 1840, when Messrs Stevenson were employed to design works for assimilating the Foss Dyke as far as practicable, both as regards width and depth, to the navigable channel of the Witham. The depth was found to be 3 feet 10 inches, and its breadth in many places was insufficient to admit of two boats passing each other, and for their convenience occasional passing places had been provided. It was resolved to increase the dimensions of the canal, and to repair the whole work. Accordingly it was widened to the minimum breadth of 45 feet, and deepened to the extent of G feet throughout. The entrance lock communicating with the River Trent at Torksey was renewed, and a pumping engine was erected for supplying water from the Trent during dry seasons, and thus that ancient canal, which is quoted by Telford and Nimmo as &quot; the oldest artificial canal in Britain,&quot; was restored to a state of perfect efficiency, at a cost of 40,000, and now forms an important connecting link between the. Trent and Witham navigations. Notwithstanding the existence of this early work, how- Bridge- ever, and of some others in the countiy, particularly the wat er Sankey Brook navigation, opened in 17GO, it cannot be cana s doubted that the formation of the Bridgewater Canal in Lancashire, the Act for which was obtained in 1759, was the commencement of British Barge Canal Navigation, of which we propose first to treat, and that Francis, duke of Bridgewater, and Brindley the engineer, who were its projectors, were the first to give a practical impulse to a class of works which, under the guidance mainly of Smeaton, Watt, Jessop, Nimmo, Rennie, and Telford, has been very generally adopted throughout the country, and has un doubtedly been of vast importance in promoting its com mercial prosperity. 4 According to Mr Smiles, the barge-canals laid out by Brindley, although not all executed by him, were : 5 Miles. The Duke s Cana], Longford Bridge to Kuncorn 24 &quot;Worsley to Manchester 10 Grand Trunk, from Wilden Ferry to Preston Brook 88 Wolverhampton 46 Coventry 36 Birmingham 24 Droitwich 5 Oxford 82 Chesterfield 46 361 It is believed that the length of the inland boat naviga tions constructed in Britain exceeds 4700 miles, and the system has been extensively carried out both in Europe and America. Many of them were made at great cost through hills and over valleys. The Harecastle tunnel on the Grand Trunk Canal, made by Brindley, and afterwards doubled by Telford, is nearly a mile and a half in length, and the Pont-y-Cyssylte aqueduct, on the Ellesmere Canal, over the Dee, constructed by Telford at a cost of 47,000, has nineteen openings 45 feet span, and is elevated 12G 3 Smeaton s Rf ports, vol. i. p. 74, London, 1812. 4 History of Inland Navigation, particularly those of the Duke of Eridfjewater, London, 1768 ; Hughes s Memoir of Erindley ; Wesile s Quarterly Papers, London, 1843. Smiles s Lives of the Engineers.