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NOTES RELATIVE TO TOWING PATHS AND BANKS OF CANALS IN GREAT BRITAIN. By M. Vuigner, Inspector of the Paris Canals. ( With an Engraving, Plate IV.) (Translated from the French.) M. Vuigner, being commissioned by the company of the Ourcq and St. Denis canals to study the various systems of works in use on the British canals, and particularly to examine the different methods used in forming the foundations of the hauling or towing paths, and protecting the slopes of the interior banks from the effects produced by the ordinary and irregular fluctuations of the water, he visited, for this purpose, in the course of 1837, the canals of that country, which stand the first in construction, and collected consider able information on the subject. In England the canals of Taunton & Bristol, those of Birmingham, (from Liverpool to Leeds) Preston & Lancaster, in Scotland those of Paisley or Ardrossan, the Forth and Clyde, and the Union Canals, fur nished him with every information that could be required. On his return to France, the company, who wished to establish on the Ourcq canal a set of passage boats, empowered M. Vuigner immediately to apply the information he had acquired. He was first engaged to macadamize the towing path of the left bank of the Ourcq canal between LaVillette and Meanx, and caused part of its banks to be im proved, and he also applied some improvements resulting from his observations in Great Britain. The present paper will contain a description relative to the metal ling of the towing paths, and the protecting of the banks on the English •and Scotch canals, as well as describing the macadamizing and facing used on the Ourcq canal to prevent damage by the action of the water. Towing or Hauling Paths. In England there is generally only one towing path, though, upon some new lines, especially the Birmingham, there are two paths. This is an exception which a particular circumstance required, but which, however, is not a deviation from the general rule. The Birmingham has a towing path on both sides until it is divided into two branches, one to Wolverhampton, and the other to Walsall, each having their towing paths, one on the right side and the other on the left. On that part where there is a towing path on each bank, the navigation is extremely active, amounting to more than 1000 boats per week. The navigation is facilitated, and at the same time the horses that tow the boats coming from Wolverhampton and Walsall have not to change their sides, nor obstruct one another. The breadth of the towing paths is generally not more than 10 feet, which is considerably less on some canals, and especially at Taunton, a canal of very small section, navigated by boats of only 10 tons. On the new line of the Birmingham canal, the breadth of the towing path in cuttings is about 12 feet, and on embankments 15 feet. The path is generally divided into three parts, one part next the canal forms a fender or raised mound 1 ft. li in. to 2 feet wide, which is turfed over, the middle part forms the trackway for the horses, and is covered with metalling or broken stone to the width of five or six feet, and the other part is the remainder of the land unappropriated; sometimes it contains a drain for carrying oil' the surface water, and is enclosed with a hedge which determines the limit of the canal pro perty. On the opposite bank, there is, in some parts, a footpath about 3 feet wide, but more frequently the underwood or cultivated land reaches to the water’s edge, so that no more land is taken than what is absolutely necessary for the canal. On the Preston, Lancaster, Paisley, Forth & Clyde, and Union Ca nals, where there are fast passage-boats, the width reserved for the fender between the towing path and the interior slope of the canal, is on the average two feet wide at the base, and raised from (1 to 8 inches above the path, or from 2 ft. to 2 ft. ti in. above the surface of the water, the top, about 1 ft. to 1 ft. 4 in. wide, is generally turfed over. The interior edge forms the continuation of the interior slope of the canal, and the outer edge is sloped aud protected with large round pebbles placed at intervals of 2 to 3 feet, which are partly imbedded in the earth, and project about 2 inches above the fender; these peb bles are now abandoned, as they were found inconvenient for the towing ropes when the speed was slackened. On some parts of the canals the fender is formed of flat stones, the edge of which forms the top of the stone facing of the bank, as shown in sections, Figs. 17, IS, and IS). The fenders answer the purpose for limiting the track of the horse, preventing the mud being washed over the path, and a pro tection to the edge of the slope. No. 43.—Vol. IV.- —April, 1841. The towing path of the above canals is mostly formed of a layer of broken or round pebbles laid to a thickness of 4 to (i inches according to the nature of the soil, and then covered with a layer of gravel from 1 in. to 1 i in. thick. On some parts marly clay is used to bind the pebbles, and on other parts, especially at the stopping places, at the bridges, ami even the whole length of the Paisley canal, the pebbles are covered with a layer of iron slag, which, when well beaten in, forms a path extremely hard and compact, besides, it is not slippery in rainy weather, and is free from dust in summer. The broken pebbles used are generally not larger than 1) inch at most. The best macadamized paths are those made of broken limestone, and better still with basalt; these materials are found nearly every where on the banks of canals, which renders their formation and repair very cheap. The transverse slopes of the towing path, where there are fast pas sage boats, have an inclination of about 2 inches to the yard declining from the canal; this inclination is found to give the best hold for the horses’ feet. The surface water is carried off on the outside of the path, and is seldom allowed to run into the canal, excepting in such parts where the canal is formed in cutting; it is then carried off by under drains of dry stones, which pass under the towing path trans versely from longitudinal gutters or drains, formed on the outside of the path. Toning Paths of V Ourcq Canal. The towing paths of this canal, and in general on all the French canals were formed on the natural soil, without the least metalling or stoning of any sort; in winter time .they were quite impassable in parts, especially in the Paris division, between La Villette and Claye. In this state of things it was difficult to think seriously of establishing passage boats, which the Ourcq and St. Denis canal company was de sirous of introducing into France; they therefore determined upon adopting the English system of macadamizing the towing path of the left bank of the Ourcq canal between La Villette and Meaux. On the Ourcq canal the ordinary boats are towed up by one horse; but the passage boats, as well as the Government boats, are towed by two horses abreast, as well going up as down, which is still the case. The experiments which were made on the speed of passage boats, showed that three horses, two horses abreast in front and one behind, were necessary for towing these boats. It thus became necessary to increase the width of the towing path. In those places where the banks had retained their first form the breadth of the path was 13 ft,, which was diminished to 11 ft. 0 in., where the banks were raised 1 ft. 6 in. above the surface of the water. The towing path is now reduced throughout to a breadth of 1) ft. G in., consisting of a fender 2 ft. wide at the base, the trackway for the horses G ft. G in. wide, and a drain 13 inches wide. In the Meaux division they have only al lowed a breadth of G feet for the towing path, but the drain has been increased to 19 inches wide, which still gives a breadth of near S feet upon which the horses can walk or run with ease. This breadth might be considered insufficient at the points of crossing, where four horses have to pass ; but the company decided that in case that should occur, they would cause the front horses to be harnessed one before the other. Another important consideration which determined the company to adhere to 9 ft. G in. was that of economy, as it would involve an extension of the work for more than 30 miles between La Villette and Meaux, and double that distance if extended between La Villette aud Mareuil. Experience has proved that the adopted width is sufficient for the different boats, as the horses of the passage boats in general never pass each other, excepting at the different stages, where the path is widened. As regards the horses of the other boats when they pass, the horses go a little on one side, or on to the exterior slopes, and if it be found too inconvenient to act thus, it is immediately obviated by har nessing the horses one before the other as before observed. The breadth being settled, it then became necessary to fix the height of the towing path above the surface of the water. Between La Villette and Meaux the top of the interior slope was S ft. above the bottom, but between La Villette. and Claye it was only G ft. G, and from Meaux to Claye 5 feet, so that the same height of path could not be adopted throughout. Between La Villette and Meaux the height of the fender was fixed at 2 ft. G in. above the surface of the water, and 6 inches above the towing path, which made the latter 2 feet above the water, as shown in sections, Figs. 5, 7, & 14. The paths were formed in some places with broken limestone, in other places with clean pebbles mixed with sand or coarse gravel, and laid to a thickness of 4 to 5 inches, and covered with a layer of gra velly sand from 1 in. to 1.) in. thick; the pebbles, when mixed with coarse gravel, were used without an extra coat, and laid to a thickness of G inches. As soon as the paths were finished,a roller 5 feet broad, Q