CHAPTER II.

ENGLISH RIVERS. “Rivers, arise; whether thou be the son Of utmost Tweed, or Ouse, or gulphy Don, Or Trent, who, like some earth-born giant, spreads His thirty arms along the indented meads; Or sullen Mole, that runneth underneath; Or Severn swift, guilty of maiden’s death; Or rocky Avon, or of sedgy Lee; Or coaly Tine, or ancient hallowed Dee; Or Humber loud, that keeps the Cythian’s name; Or Medway smooth, or royal-towered Thame.” —_Milton._ One of the earliest pioneers of inland navigation was Wm. Sandys, of Ombersley Court, in Worcestershire, who, in 1636, applied for Parliamentary powers to make the river Avon navigable for boats and barges, from the Severn at Tewkesbury to the city of Coventry. Part of the work which was executed in pursuance of the powers so obtained exists to the present time. In 1661 Sandys sought for Parliamentary authority to make the Salwarp navigable from the Severn to his own town of Droitwich, and to make navigable the rivers Wye and Lug, and the brooks running into the same in the counties of Hereford, Gloucester, and Monmouth. Our great rivers, the Thames, Severn, Trent, Ouse, &c., were the recognised means of transit long before the time of the Romans, who were so far advanced in inland navigation as to cut canals of forty miles in length, as instanced in the Caerdyke, between Peterborough and Lincoln (though now filled up), as also to build docks, as shown in the old dock walls, &c., still standing at the outfall of the Trym into the Avon below Bristol. The Fossdyke navigation from Lincoln to the Trent is also of Roman origin, and probably an extension of the Caerdyke, on their route to York. Torksey, at the junction with the Trent, was a Roman town and fort, and continued possessed of many privileges, down to the Norman period, on condition that the knights who held it should carry the King’s Ambassadors, as often as they came that way, down the Trent in their own barges, and conduct them to York. This is recorded in ‘Domesday Book.’ Itchin Dyke to Winchester was also cut by the Romans. It is usual to date the first beginning of canal navigation in England from the time when Brindley constructed the famous canal between Worsley and Salford for the Duke of Bridgwater. This, no doubt, was the first important artificial navigation throughout. But Sandys had practically undertaken canal construction about a hundred years before. The Act of Parliament which sanctioned the various enterprises that he had projected, authorised him to construct new channels, and to set up, in convenient places, “locks, wears, turnpikes, penns for water, cranes, and wharfs, to lay timber, coals, and all other materials that shall be brought down;” to have and use “a certain path, not exceeding four feet in breadth, on either side of the said rivers and passages,” for the “towing, pulling, or drawing-up of their barges, boots, leighters, and other vessels passing and repassing them, or any part of them, by strength of men, horses, lines, ropes, winches, engines, or other means convenient;” and “to dig, carry, trench, or cut, or make any trench, river, or new channel, or wharf,” &c., after having arranged with the “respective Lords, owners, or occupiers of the said lands.”[29] Sandys, however, did not succeed in carrying out the intended navigation between the cities of Hereford and Bristol as he proposed. He attempted to make the Wye navigable by locks and weirs on the pound-lock system, which did not suit its rapid current. The enterprise was accordingly abandoned, after a trial of several years. In 1688 the project of making the Wye navigable was revived. It was now proposed to abandon the pound-lock system, to purchase and remove all the mill-weirs and fishing-weirs between Hay, in Herefordshire, and the sea, and to deepen the channels of the shallow streams. The weir-owners rose in opposition to these proposals, and for several years the subject was the occasion of a bitter controversy. When the Bill was applied for in 1695, the city of Hereford, and thirty-two parishes in the county, petitioned in its favour; while the towns of Ross and Monmouth, and thirteen parishes, petitioned against it. The Bill, however, ultimately became law,[30] and although, owing to the uncertainty of its depth and current, the Wye was never adapted for regular navigation, it was so far improved that throughout the eighteenth century it was of great service to the county of Hereford.[31] One of the earliest to advocate river improvements in Britain was Andrew Yarranton, an original genius, who had ideas and plans quite a hundred years in advance of his times.[32] He occupied himself with many different projects designed to effect improvements in means of communication, and in developing the resources of the country generally. At one time serving as a soldier, at another engaged in the manufacture of iron; now planning how to provide employment for the poor, and again studying how to bring about more economical processes of husbandry, Yarranton made a special hobby of the improvement of navigation, undertaking surveys of the principal rivers in the West of England at his own cost, and urging upon the people the importance of opening up the facilities of communication thereby available to them. In 1665 Yarranton proposed to the burgesses of Droitwich to deepen the small river Salwarp, so as to connect that town, now an important centre of the salt industry, with the river Severn. He was offered terms to carry out his plans, but the offer does not appear to have been good enough.[33] In 1666 Yarranton proposed to make the river Stour navigable between Stourport and Kidderminster, and to connect it with the river Trent by a navigable canal. He carried out this work so far as to make the river navigable from Stourbridge to Kidderminster; but his scheme was not completely adopted for lack of means. He says that he “laid out near 1000_l._,” and “carried down many hundred tons of coal,”[34] although, on account of the novelty of his enterprise, it was greatly ridiculed. At a later date Yarranton proposed to connect the Thames and the Severn by means of an artificial cut, “at the very place where, more than a century after his death, it was actually carried out by modern engineers.”[35] Although the proprietors in what was called the “Old Quay Company” had obtained an Act of Parliament in 1733 for improving by weirs and cuts the rivers Mersey and Irwell, between Runcorn and Manchester, the first association incorporated for making a regular navigable canal in England was not till more than twenty years later, six centuries after the first canals in Italy and Flanders, and a hundred years subsequent to some of the chief canals of France being in operation. It is but fair to add that England carried the movement further than most other countries. It is unnecessary to enter into the history of the development of the navigable resources of the rivers of the United Kingdom during the last two centuries, even if it were possible, which, of course, it is not in a work of this description. The dates when the several principal navigation works were undertaken will be found set out in Appendix I. But we may, nevertheless, bestow some consideration upon the principal steps that have brought about the remarkable facilities that England, Scotland, and, to a less extent, Ireland, respectively enjoy at the present time in the matter of internal transport. The Clyde, the Tyne, the Tees, the Wear, and other prominent English rivers have been transformed from shallow brawling streams, some of them easily fordable at all states of the tide, into magnificent waterways, capable of bearing on their bosoms the largest vessels afloat. This work has necessarily involved great engineering capacity, a large expenditure, and a judicious administration of their powers and resources by the public bodies through whom it has been carried to completion. THE MERSEY. On the Liverpool side of the Mersey there are sixty docks and basins of the ordinary type, having a total water area of 368 acres and 25 miles of quay berthing. On the Birkenhead side, there are 164½ acres of docks, with 9½ miles of quayage, three graving docks, having a total length of 2430 feet, and every facility for loading and unloading ships. The total expenditure incurred on this enormous provision for shipping has been upwards of twenty millions, and the total annual revenue of the Mersey dock estate is about a million and a half sterling. The entire length of the Mersey is 56 miles. For the first 37 miles of this distance, the river has a tortuous course, ill-adapted for navigation, and passes through an almost exclusively agricultural country. From Runcorn to the sea, the form of the river is that of a bottle, of which the wide expanse between Runcorn and Liverpool forms the body, and the narrow part opposite Liverpool the neck. Through this neck there annually passes nearly twenty million tons of shipping, including entrances and clearances. The unassisted efforts of nature have hitherto maintained the navigable channels of the Mersey, so that the conditions of navigation remain practically uniform. The bar, however, is gradually moving in a seaward direction, while maintaining its general form and characteristics. In Liverpool Bay there is a great range of tide, which insures a depth of at least 30 feet over the bar once in every twelve hours, even on the lowest neaps. Some two or three million cubic yards of upland water every twelve hours are discharged into the estuary, chiefly by the Mersey and the Weaver, which, with 710 million cubic yards on a high spring tide, maintains the normal capacity of the estuary, and counteracts the process of silting. Some 17,300 acres of a deposit of sand in the estuary are above the low-water mark. Through this the upland water forms and maintains a channel in its course to the sea, and any serious exclusion of this tidal water would be likely to so far injure the sea channels as to interfere with the trade and shipping of the port. The Mersey is the outlet for several important canal navigations, including the Weaver Navigation Canal, near Weston Point, the Bridgwater Canal at Runcorn, the Sankey Canal at Widnes, the Shropshire Union Canal at Ellesmere, the Leeds and Liverpool Canal at the Docks, and the Manchester Ship Canal, now under construction, at Eastham. The position of these several canals in relation to the river may be traced in a map accompanying a paper read by Mr. Lyster, the engineer, before the Institution of Naval Architects. These canals are important factors in assisting the growth of the trade of the Mersey. The Leeds and Liverpool is, however, the only canal that has a direct connection with the Liverpool Docks. By this canal Liverpool has water communication with the important town of Leeds, and thence, by the Aire and Calder Canal, with Hull and the other ports on the Humber. By the Shropshire Union Canals the Mersey is connected with the network of canals in the Midland Counties and with the River Severn. In Camden’s time Liverpool must have been a very obscure place. The author of ‘Britannia’ dismisses it almost in a sentence, observing that “from Warrington, the River Mersey, spreading abroad, and straightwaies drawing in himselfe again, with a wide and open outlet, very commodious for merchandise, entereth into the Irish Sea, where Litherpoole, called in the elder ages Lipen-poole, common Lirpoole, is seated, so named, as it is thought, of the water spreading itself in manner of a poole.” With the exception of the Thames—which it rivals, and with which for a number of years past it has run a neck-to-neck race—the Mersey is, so far as its volume of business is concerned, the most important river in the world. This, however, is an attainment of comparative modern origin. The first wet dock was constructed at Liverpool, in 1708-9, on the site now occupied by the Custom House. In the latter part of the same century several other docks were constructed. The dock estate has now an area of 1078 acres, the whole of which is appropriated to basins, docks, quays, and premises worked in connection therewith. THE WEAVER. The history of the navigation of the river Weaver, which adjoins the Mersey in Cheshire, supplies a notable example of what may be made of an originally insignificant and tortuous stream in order to adapt it for the requirements of commerce. The river has been canalised between Northwich and Chester, twenty miles of the navigation being artificial navigation, and the other thirty miles being river proper. In 1721 three Cheshire gentlemen obtained the first Act of Parliament for making the river Weaver navigable. The depth then provided for was only 4 feet 6 inches, and boats of more than 40 to 50 tons could not enter. About the year 1760, the navigation was carried down so as to enable vessels to enter at nearly all tides, and in 1810 the river was further improved by the Weston Canal, which is four miles long, enabling vessels of much deeper draught to enter without navigating a dangerous part of the old river. This canal forms a junction with the Bridgwater Docks at Weston Point, and a dock was formed in connection with it so as to enable vessels to wait for the tide. In 1830 the depth was increased to 7 feet 6 inches, with locks 88 feet long and 18 feet wide, capable of taking cargoes of 100 to 150 tons. There were at this time eleven single locks on the river, not including the entrances to the Mersey. About 1860, a second set of locks, having 10 feet of water on the sills, and 100 feet long by 22 feet wide, was placed by the side of the existing locks, and the number was reduced to nine pairs. The larger size, owing to the vessels being built almost to the shape of the lock, were capable of passing vessels with nearly 320 tons on board. This continued until about seventeen years ago, when it was decided to replace these locks by some of very much larger dimensions, and also to greatly reduce the number. With this object, locks were built at Dutton and Saltersford near the site of existing locks, and of sufficient height of walls to enable the two ponds above to be thrown into one, thus doing away with the four smaller locks. The same has been done at Hunts, and, more recently, at Valeroyal, above Northwich. The locks at Dutton and Saltersford are entirely built of masonry, having limestone sills and rubbling courses, with the intermediate part sandstone. All the work on the river is of this description, with the exception of the Hunts and Valeroyal large locks, which are built of concrete. When these improvements are completed there will be only four locks on the twenty miles of navigation, the larger of each pair of locks being 220 feet long, by 42 feet 6 inches wide, and having 15 feet of water on the sills. Most of the river is now dredged to 12 feet, there only being 10-feet bars at certain points. The ordinary width is about 95 to 100 feet at water level, and 45 feet at the bottom. More than a million tons of salt annually pass down the Weaver to the Mersey. THE TYNE. This noble river, from Newcastle to the sea, is one of the greatest triumphs of modern engineering. Good old Camden quaintly remarks, that “where the wall (Roman) and the Tine almost met together Newcastle sheweth itself gloriously, the very eye of all the townes in these parts, ennobled by a notable haven, which Tine maketh, being of that depth that it beareth very tall ships, and also defendeth them, that they can neither easily be tossed with tempests nor driven upon shallows and shelves.”[36] No better example of what has been done within recent years in the way of providing additional facilities for the wants of British shipping, could be quoted than the case of the Tyne. That river is the natural outlet of the great northern coalfield. It is also the outlet for a very great trade in chemicals, engineering, iron and steel, and other industrial products. But in order to adapt it for the purposes of its large and rapidly-growing commerce, it was necessary not only to provide several docks—the more important of which, the Northumberland and the Coble Dene, cost 352,000_l._ and 528,000_l._ respectively—but it was also requisite to expend over 1,300,000_l._ in dredging the bed of the river, so as to provide access for the largest size of vessels, to expend nearly three-quarters of a million on other river works, to construct North and South Piers at a cost of over 820,000_l._; and to incur a total outlay considerably exceeding 4,000,000_l._ The effect of these improvements and structural works has been that the Tyne has been transformed from “a series of shoals, with a narrow and generally serpentine channel between and past them, through which vessels of about 15-ft. draught could get up at high-water spring tides, whilst at low-water it was a not uncommon occurrence for small river steamers, drawing from 3 to 4 ft. of water, to be aground on their passage between Shields and Newcastle for three or four hours,” to a magnificent navigable highway, that admits vessels of 3000 tons and upwards at all states of the tide with perfect safety. At the time that the great work was commenced, and for many years afterwards, the revenue from shipping dues was quite insufficient to enable any substantial progress to be made, and the trade grew so rapidly that it became imperative to either borrow money in order to carry out the required works, or allow the shipping to seek other ports, where better facilities were provided. The works to the end of 1882 had, therefore, to be chiefly carried out by the aid of borrowed money. As a matter of fact, only 426,000_l._ was expended out of income, while 3,673,000_l._ was borrowed. The results, however, appear to have justified the course. The annual income from dues and tolls has grown, within twenty years, from 91,000_l._ to over 251,000_l._ The Tyne Improvement Commission, chiefly under the presidency of Sir Joseph Cowen, have deepened the river to a uniform depth of nearly 30 feet, built training walls, dredged the bar, built new channels, and otherwise revolutionised the old order of things. The results have been extremely striking. In 1888 14,668 vessels, having a total tonnage of 6,734,000 tons, cleared from the Tyne ports; while 6093 ships, having 1,662,000 tons register, entered the same ports. The people of Tyneside are proud of their river, as well they may be. THE RIBBLE. Preston is a busy town and port in the county of Lancashire, situated on the river Ribble, about seventeen miles from the sea. The navigation of the port has hitherto been confined to coasting vessels drawing about 14 feet of water. The amount of shipping entering the port has been under 30,000 tons a year. The Ribble rises in the West Riding of Yorkshire, at the east foot of Whernside, and arrives at Preston after a course of fifty-seven miles. With its tributaries it drains about 800 square miles of land, a great part of which is moorland. The annual rainfall over this district averages about 37 inches. Below Preston, the channel of the river opens out into a broad sandy estuary, four or five miles in width, the whole of which is covered at high water of spring tides, and the greater part of which is dry at low water. The course of the river, after it leaves the trained portion, is along the northern shore of this estuary to Lytham, whence the main navigable channel, called “The Gut,” bends in a south-westerly direction between the Salt-house and the Horse-shoe banks to the Irish Sea. The width of the estuary between the two forelands on the coast, Stanner Point on the north, and Southport on the south, is five miles. The sands extend four miles seaward beyond this line, and are uncovered at low water. The depth at low water spring tides on the bar, or the portion of the navigable channel with deep water, is four feet. Beyond this the depth seawards rapidly increases, from 20 feet immediately beyond, till, at the Nelson buoy—which is two miles beyond the bar, and the first buoy belonging to the Ribble navigation—the depth is six fathoms. The depth above the bar along the Gut channel, which is rather tortuous and narrow, being shown on the Admiralty chart as less than a quarter of a mile wide, varies from 4 to 24 feet. This channel is buoyed out with eight buoys, which are shifted as the channel varies. There are three other channels between Lytham and the sea, called, respectively, the South Channel, the Penfold, and the North Channel. These are more or less navigable; but the Gut is the main sea-fairway. From Lytham a shallow channel runs near the shore for about a mile to “The Dock,” where ships can lie at anchor. Thence it winds towards the Wage through the sands. This channel is continually shifting its course, owing to gales and freshets. From this point the river has been trained by rubble-stone training walls, put in about thirty-four years ago, which continue for seven miles up to Preston. These walls rise seven feet above low water, and are 300 feet apart at the top. Spring-tides rise 24 feet at the bar, and neaps 17 feet, and at Preston the rise is 10 feet and 4 feet 6 inches. The project of constructing a dock at Preston has been agitated for some years, and has been strongly advocated by Mr. Garlick, M.I.C.E., who was the engineer to the Navigation Commissioners. It was considered that by providing deep-water accommodation to the town, its trade and prospects would be greatly increased, having regard to the large manufactories by which it is surrounded, the immense population in the immediate neighbourhood, and the nearness of the Wigan coalfield. This work is now in progress, including the division of the river; the estimated cost being about 440,000_l._ THE SEVERN. This famous river is navigable up to Welshpool, a distance of 155 miles by water, from the mouth of the Bath Avon river. The extreme branch of this river may be traced for about 45 miles above Welshpool, to Plinlimmon Hill, and numerous other branches extend for great distances into the country on both sides. The whole of this great length of navigation was, till lately, unimproved by art, the river having no locks, weirs, or other erections throughout its whole length, for surmounting the numerous shallows and irregularities which the current over variable strata had formed in its bed. The first or lowest 42 miles of this river, extending to the city of Gloucester, are very wide for a great part of the way, and have a most rapid tide; but the last 28 miles are so crooked, that ships are said to be often several days in passing it; on which account, a ship canal, calculated for vessels of 300 tons burthen, was in the year 1793 projected and begun between Gloucester and Berkeley, of 18¼ miles in length, for avoiding these 28 miles of the river. From Gloucester to Worcester the distance is 30 miles by the course of the stream, the rise in this length being 10 feet, or at the rate of 4 inches a mile; from Worcester to Stourport the distance by water is 13 miles, and the rise 23 feet, or at the rate of 1 foot 9 inches per mile; from Stourport to Bridgnorth it is 18 miles, and the rise 41¾ feet, or 2 feet 4 inches per mile on the average; and from Bridgnorth to the new town at the junction of the Shropshire canal, called Coalport, the distance is about 7 miles, and the rise about 19 feet, being a rate of about 2 feet 8 inches per mile. William Reynolds, the founder of Coalport, caused an account to be daily registered of the depth of the stream in the bed of the Severn at that place, between the 7th of October, 1789, and the 23rd of December, 1800, of which Mr. Telford has given the particulars, except on twelve occasions when the river had overflown its bounds and covered the usual marks (on Sundays during some part of the time), the intervals of frost in which the river was frozen over, and for three short intervals, when, unfortunately, the experiment was by some accident suspended. During all the months of January, in the above period of eleven years, ending the 6th of October, 1800, the river does not appear to have exceeded the depth of 16 feet, that being the greatest depth at any time recorded; and several times, when no depths are inserted to the great floods, it is stated in the table that the water was above all the marks. Besides these, there were thirty-two smaller floods, or times when the water had risen, and was falling again for some days after; the highest of these had a depth of 13 feet (5th January, 1790), the lowest 4 feet, and the mean of the whole of these floods is 7½ feet. In the months of February there were two of these overflowings, one of which (11th February, 1795) followed a frost and continued for five successive days: nineteen floods, the two highest of which were equal (17th and 20th February, 1799) to 12 feet. THE WITHAM. On the Witham, for a distance of thirty miles, between Boston and Lincoln, the river is practically a canal. The tide is stopped by a sluice at Boston, and a weir and locks had to be constructed at Bardney and Lincoln. The inland water is held up to a constant height on the sill of this sluice by penstocks, for the purposes of the navigation. The navigation having been taken over by the Great Northern Railway Company, the works are maintained in efficient condition; but the obligation imposed by the original Act of holding up the water seriously affects the drainage. The river Slea, from Sleaford to the Witham, was made into a canal in 1792. The navigation on this river having almost entirely ceased, the company was dissolved by an Act of Parliament. The Bane, another affluent of the Witham, was also canalised, forming a navigation from the Witham to the town of Horncastle; but the dues obtained are insufficient to maintain the works in proper order. THE NENE AND OUSE. On the Nene, which is canalised from Peterborough to Northampton, the navigation is reduced to a few barges. The constant floods on this river are ascribed in a great measure to the defective condition of the works. The proprietors of the navigation, on whom was cast the duty of maintaining the river, no longer have the funds, and there is nobody to take their place. The same thing has occurred on the Ouse between Earith and Bedford. On some of the affluents of these rivers, which, under legislative powers granted last century, had been converted into “navigations,” the proprietors have obtained Acts of Parliament relieving them of their rights and liabilities, and there is now no jurisdiction over these rivers, or anybody responsible for removing shoals or cutting weeds. The beds of these streams have consequently become shallow, and they are no longer capable of acting as efficient arterial drains. Thus, on the Ivel, an affluent of the Ouse, the navigation trust, created in the reign of George II., was abolished in 1876. The river is said to have since diminished one-half in width, and one-half in depth, and the bottom is being gradually raised to the level of the land. In like manner, the Lark, another canalised affluent, has almost entirely silted up since the navigation of the river ceased. The Ouse itself, above Earith, is obstructed by numerous shoals, and an enormous growth of weeds. These were originally kept down by the constant passage of the vessels, and the shoals were removed by the trustees of the navigation. THE TEES. The improvements that have been carried out for the purpose of opening up the navigation of the river Tees, although less considerable than those carried out for some of the larger rivers of Great Britain, are yet entitled to take rank as among the most notable river engineering achievements of the century. They are also among the most recent. It was not until 1852 that the Act was passed creating the Tees Navigation Commission. At that time there were three or four channels in the estuary, all of them very shallow. The shifting sandbanks caused great trouble and not a little danger to navigation, and the depth of water near to Middlesbro’ did not admit of the passage of vessels of large size. Since then, about twenty miles of low water training walls have been erected for the purpose of confining the navigable channel. The volume of water and its scour have thereby been much increased. The river has been continuously dredged in order to secure a depth of water that would allow of the passage of vessels of large tonnage into the Middlesbro’ Docks. About 23 million tons of material have been dredged from the bed of the river, and the channel has been generally straightened and widened. Breakwaters have been constructed on both sides, one of them, called the North Gare, being about two miles and a half long. A remarkable feature of the work is that these breakwaters have been constructed of slag, obtained from the blast-furnaces in the neighbourhood. Some millions of tons of slag have been employed in this way, the ironmasters having paid to the Conservancy Commissioners a small sum for removing the slag, the disposal of which had been a great source of difficulty previous to this application. As a result of the works that have been carried out for the improvement of the navigation of the Tees, the shipping trade of the river, and especially of the port of Middlesbro’, has greatly increased. The main element in this development has been the growth of the iron industry; but the second element has undoubtedly been the increased facilities for navigation. The popular impression about Middlesbro’ is that only a single house stood in 1830, where there is now a busy town of more than 70,000 inhabitants. This may or may not be a legend, but there is no doubt about the fact that in 1850 there were only from two to three feet of depth on the bar of the Tees, where it was possible to wade across at low water; whereas now there is about 20 feet of water, and a harbour of refuge has been provided in which ships can ride in safety whatever the condition of the usually stormy seas outside. THE IRWELL. This river has been partly canalised, in order to afford a means of communication between Warrington, Manchester, and other large towns, and Liverpool, but it was only adapted for light craft and has consequently fallen largely into disuse. The Mersey and Irwell Navigation was acquired by the Bridgwater Company, and has now, with the rest of the Bridgwater property, passed under the control of the Manchester Ship Canal Company. THE WEAR. This river, which has its rise in the district that unites Durham and Westmoreland, falls into the North Sea at Sunderland after a course of thirty miles. The river is under the jurisdiction of the Wear Commissioners from about nine miles from the bar to the sea. Over this distance very considerable improvements have been carried out during the last half century. These improvements have resulted in making the Wear one of the foremost shipbuilding rivers in the United Kingdom, and have given it the second place in the coal-shipping trade. The revenue of the Wear Trust, which only averaged about 14,000_l._ a year between 1840 and 1850, has within recent years amounted to about 130,000_l._ a year. One of the most extensive works undertaken on the river, besides graving docks, wharves, &c., and the deepening of the bed, was the construction of a lock at the sea outlet, designed to obviate the detention of screw-colliers when waiting for the tide. This lock is 481 feet in length by 90 feet in breadth, and has a depth of 29½ feet at ordinary spring tides. The present docks can accommodate 200 ships of large size, drawing up to 24 feet of water. The area of the docks is over 78 acres, and they are fitted with nineteen coal spouts, at which 15,000 tons of coal can be shipped daily. In this chapter we have dealt with a few only of the more notable examples of river improvement in modern times. The list might be almost indefinitely extended. There is hardly a brawling mountain torrent between Land’s End and John o’ Groat’s that has not been reclaimed, deepened, widened, or otherwise improved upon by the art and the genius of the engineer. Nor has the work been confined to modern times. The Romans are known to have constructed embankments for the control of British rivers during the period of their occupation, although for something like 1000 years afterwards their example was not followed. The engineers and the local authorities of the nineteenth century have done much to redeem this reproach. The improvement and conservancy of rivers have now been reduced to a science, founded mainly upon the following general principles[37]:—