The whole course of the river, from its source to the Nore, is reckoned at from 205 to 210 miles.

The removal of the old London Bridge has caused a considerable change in the river above, and also, though in a less degree, below the bridge. Owing to the contracted arches through which the water had to make its way at the old bridge, there was a fall of from 4 feet 9 inches to 5 feet at low water; this fall is now reduced to about 2 inches; so that the low water line above the bridge is nearly 5 feet lower at spring tides than formerly. In consequence, a greatly increased body of tidal water now flows up and down the river; and as it meets with no obstruction, it flows with a decidedly greater velocity. The effect of this is to scour and deepen the channel of the river; its influence in this respect being already sensibly felt as far up as Putney Bridge, 71⁄2 miles above London Bridge. The shores above the latter, that were formerly foul and muddy, are now becoming clean shingle and gravel, and near low water the beach is quite hard and firm. The shoals are also decreasing below the bridge; and there can be little doubt that the change will, at no distant period, be felt from the Nore up to Teddington.

Before the removal of the old bridge, a barge, starting from the pool with the first of the flood, could not get farther than Putney Bridge without the assistance of oars. But, under similar circumistances, a barge now reaches Mortlake, 4 miles farther up, before using oars, and with a little help she may reach Richmond; and taking horses there, may get to Teddington in a tide. The descent down the river has been equally facilitated; the mean velocities of the flood and ebb between London Bridge and Westminster Bridge, are flood, 3 miles an hour, extreme, 34; ebb, 31, extreme, 34.*

Of the tributaries of the Thames, the Kennet, Wey, Lea, and Darent only are navigable, and are, therefore, the only ones that we need notice. "The Kennet swift, for silver eels renowned," rises on Marlborough Downs, in Wiltshire, and, pursuing an easterly course, falls into the Thames at Reading. It has been made navigable as far as Newbury; whence the canal previously mentioned is carried by Devizes and Bradford to Bath and Bristol. The Wey falls into the Thames near Oatlands; it has its source in the eastern part of Hampshire, and has been rendered navigable from Godalming to the Thames, a distance of about 20 miles. The first navigation locks used in England are said to have been constructed on this river. The Lea rises in the chalk hills near Luton, in Bedfordshire; and, pursuing a southerly course, falls into the Thames near the East India Docks. It has been made navigable, by collateral cuts and otherwise, as far as Hertford. This navigation, which is of considerable importance, began to command the attention of the legislature so early as 1425, in the reign of Henry VI. It has not even yet, however, received all the improvement and extension of which it is capable. -(Priestly on Inland Navigation, &c. p. 411.) The Darent has its source near Westerham, in Kent; it falls into the Thames about four miles below Dartford, to which it is navigable.

We are indebted for these details to John Smeaton, Esq., assistant to Messrs. Rennie, the engineers.

The Medway can hardly be called a tributary of the Thames; but as it falls into the estuary of the latter, it may be most properly noticed in this place.

The Medway was called by the ancient Britons Vaga, to which the Saxons prefixed the syllable Mad, signifying mid or middle, because it ran through the middle of the kingdom of Kent: hence it came to be called Medweg, and latterly Medway. — (Hasteď's Kent, 8vo. ed. vol. i. p. 273.)

This important river rises in the south-east corner of Surrey, between the north and south chalk ranges; being joined at Penshurst Place by streams from the north of Sussex. Its course is thence north-east to Maidstone, and then north to Rochester and Chatham; about two miles below which it turns nearly east, expanding at the same time into a wide æstuary interspersed with islands. After prosecuting an easterly course for 8 or 10 miles, it turns once more to the north, falling into the mouth of the Thames at Sheerness. The tide is interrupted by locks, otherwise it would flow up the river to Maidstone. In consequence of works begun in the reign of Charles II., and resumed at different subsequent periods, it has been rendered navigable as far as Tonbridge; affording a channel of communication of much importance to the surrounding country. From Sheerness to Chatham there is water to float the largest ships; and the ground being soft, and the reaches short, it forms an admirable harbour for men-of-war, many of which are usually laid up here when out of commission. The arsenal at Chatham is one of the most important in Great Britain. Considering the shortness of its course, the Medway is one of the deepest of European rivers.

In 1667, the Dutch, under De Ruyter, took Sheerness; and, sailing up the river as far as Chatham, destroyed several sail of the line and a great quantity of stores. They accomplished this daring and brilliant achievement without incurring any material loss; but the fortifications were soon after so much improved and strengthened, as to render a coup de main of this sort no longer possible.

The Stour, the Colne, and the Chelmer fall into the mouth of the Thames at different points on the Essex coast. The Stour rises near Haverhill, on the confines of Essex, Suffolk, and Cambridgeshire. Having passed Sudbury, to which it is navigable, and Manningtree, it falls into the mouth of the Thames at Harwich. The harbour of the latter is of great extent, and has sufficient water to float ships of the largest class; but the access to it is a good deal obstructed, so that a pilot should be always employed. The entrance to the harbour is marked by two lighthouses. The Colne is navigable from Colchester to the mouth of the Thames; and the Chelmer from Chelmsford to the estuary of the Blackwater, and thence to that of the Thames.

The basin of the Thames, that is, the country drained by it and its tributary streams, including the Medway, is of large extent, and is exceedingly populous: it comprises the greater part of Kent, with the whole of Surrey, Berks, Oxford, Bucks, Herts, Middlesex, Essex, and Suffolk, with part of Gloucester and Wilts, being an area of about 8,500 square miles, containing, in 1831, about 3,500,000 inhabitants;

so that on this space, including between one sixth and one seventh part of the surface of England and Wales, is accumulated between a third and a fourth part of their inhabitants, and decidedly more than the third part of their wealth.

This statement seems sufficient to show that the fears of those who anticipate any great falling off in the trade of London must be, in a great degree, imaginary. The foreign trade of Liverpool, Glasgow, and Hull, particularly the first, from their situation in the coal and manufacturing districts, may, it is to be fairly presumed, continue, as it has done for the last half century, to increase more rapidly than that of the metropolis. But we do not think that there is much reason to apprehend any material falling off in the trade of the latter. The great population and vast wealth of the basin of the Thames seem quite sufficient, exclusive of its advantageous situation, to insure the ascendency of London as an immense commercial entrepôt.

Severn, &c.- The Severn, the second river in the kingdom in point of magnitude, and perhaps, also, in importance, has its principal source in a small lake on the eastern side of Plynlimmon mountain, in Montgomeryshire. At its outset it is called the Hafren; the name by which, through its whole course, it was known to the Britons. It flows first towards the south-east, and afterwards turns to the north-east as it approaches Newton, where it takes the name of Severn. Hence, through the vale of Montgomery, its course is almost due north; till, entering the great plain of Salop, beyond Welshpool, it turns abruptly to the south-east; and pursuing the same direction, it almost encircles Shrewsbury. Flowing through Colebrook Dale, and passing Bridgenorth, it follows a southerly course as it leaves Salop, and enters Worcestershire at Bewdley. Being now become a broad and deep river, crowded with barges, it rolls through a pleasant country in a tranquil stream, passing the city of Worcester, and traversing the vales of Evesham and Gloucester. In the latter it divides into two channels, one of which washes the walls of Gloucester; but, being again united, it forms a great tidal river. Its course from Gloucester to Nass Point is tortuous; from the latter it flows south-west, till it assumes the name of the Bristol Channel, expanding and insensibly losing itself in the Atlantic Ocean.

The Severn, particularly below Gloucester, has frequently overflowed its banks, and occasioned much damage to the surrounding country. It is remarkable for its tide, which rushes in with a head 4 or 5 feet high, and a loud noise. This, no doubt, arises from the wide expanse of the waters of the Atlantic in the Bristol Channel being gradually narrowed, till at length they are forced violently up the river. Outside the Bristol Channel, spring tides rise from 22 to 24 and 26 feet; but in King's Road, at the mouth of the Lower Avon, they rise to the height of 48 feet, and sometimes more; and at Chepstow the rise is 60 feet.* The opposition which the current

from the sea meets with from the adverse current of the river occa

Norie's Sailing Directions for the Bristol Channel, p. 20.

sions that dashing and grinding of the waves known by the name of hygre or eagre.

The Severn is navigable from the Flatholm Lighthouse, where it loses itself is the Bristol Channel, to Welshpool — a distance of about 178 miles; and its navigation is continued by the Montgomery canal to Newton. It is, consequently of the highest importance as a channel of internal communication; its capacity in this respect being materially increased by its numerous large tributary streams, and by the canals and railroads that join it. By means of the latter, it commands a large share of the commerce of Birmingham, and of the various trading towns of Staffordshire, Warwickshire, &c.; and is united with the Thames, the Trent, and the Mersey. From Welshpool to the sea it has a gradual fall of 225 feet. — (Priestley on Inland Navigation, &c. p. 596.)

The navigation of the Severn from Nass Point to Gloucester is both tedious and difficult. To obviate this inconvenience, a canal on a large scale has been dug from Berkeley-pill to Gloucester. It is 18 miles long, from 70 to 90 feet wide, and from 15 to 18 feet deep; and may consequently be navigated by vessels of 350 tons. There is a basin at each end for the accommodation of shipping. This canal, which was opened in 1827, has become the channel of an extensive commerce; and Gloucester is now rising fast in importance as a trading and shipping town.

The barges which navigate the Severn are about 120 feet in length, from 19 to 20 in breadth, and 5 in depth. They carry above 100 tons. The trows are from 60 to 70 feet long, 20 broad, and 5 deep, carrying 75 tons. They carry a square-sail, and have a mainmast and topmast.

Of the tributaries of the Severn, the most important are the Teme, the Upper and Lower Avon, the Wye, and the Usk. The Teme, rises in the mountains which divide Radnor and Montgomery shires; and, pursuing a south-easterly course, joins the Severn Worcester.

near

The Upper Avon rises on the confines of Leicestershire and Northamptonshire, about 300 feet above the level of the sea. It flows in a south-westerly direction, but with a very winding course, through Warwick, Stratford-on-Avon, and Evesham, falling into the Severn at Tewkesbury. It has a large body of water; and is navigable by barges for about 40 miles, or from the Severn to Stratford, where it is joined by the Stratford canal.

The Lower Avon has its source near Malmesbury, in North Wiltshire. Its course is circular, passing Chippenham, Bradford, Bath, and Bristol. As a shipping and commercial town, Bristol used to be second only to London; but though now far surpassed by Liverpool, and also by Newcastle and Hull, it is still a place of great trading importance. It is situate about 8 miles above where the Avon falls into the Bristol Channel; but, owing to the great rise of the tide, the largest class of merchantmen reach the quays without difficulty. A lateral canal accompanies the river from Bristol to Chippenham.

The Wye, the largest of the tributaries of the Severn, is justly celebrated for its romantic and beautiful scenery. It rises on the

south side of Plynlimmon, near the source of the Severn; and pursuing a south-easterly winding course, falls into the latter a little below Chepstow. It is navigable for barges from its mouth as far as Hay, in Brecknock- a distance by water of about 100 miles; but the navigation in the upper parts of the river is liable to much interruption, sometimes from a scarcity of water, and sometimes from floods, The latter are occasionally so violent as to make considerable alterations in the bed of the river. Its principal tributaries are the Lugg and the Munnow. Owing to its being the entrepôt of the country traversed by the Wye, Chepstow has a good deal of trade. The tide, as already mentioned, rises here to the extraordinary height of 50 or 60 feet, and sometimes more. Vessels of the largest burthen may consequently come up to the town. Owing, however, to the violence of the ebb and flow, the navigation is rather dangerous.

The Usk rises in Brecknockshire; and, taking an east and south course, falls into the Severn about 4 miles below Newport. It is navigable to the latter for the largest ships. The Brecon and Abergavenny canal terminates at Newport; and it also communicates with various railroads. In consequence, partly of this command of internal intercourse, and partly of the rapid increase of iron-works in Monmouthshire, Newport has become a place of considerable commercial importance.

Besides the affluents now mentioned, the British Channel or embouchure of the Severn, receives the rivers that drain Glamorganshire, Caermarthenshire, and the greater part of Pembrokeshire. Of these the Taaf, the Neath, and the Towey are the most important; but with the exception of the latter, which is navigable as far as Caermarthen, none of them seems to require any particular notice.

On its southern side, the Bristol Channel receives the rivers of Somersetshire. Of these, the Parret is by far the most important. It rises a little to the south-east of Crewkerne, on the borders of Dorsetshire, and, flowing northwards, is joined by the Yeo or Ivel, which passes through Ilchester; and by the Thone, which passes through Taunton. The Parret is navigable for vessels of 200 tons burthen to Bridgewater; the Yeo, or Ivel, is navigable as far as Ilchester; and a canal has been cut from Bridgewater to Taunton.

It is clear, from these statements, that the basin of the Severn is of great extent and importance. It includes the counties of Somerset, Worcester, Warwick, Salop, Montgomery, Radnor, Hereford, Monmouth, Glamorgan, Brecknock, Caermarthen, with the greater part of Gloucester, Pembroke, and part of Wilts. Its total area may be taken at about 11,600 square miles, having, in 1831, a population of about 2,150,000.

Trent, &c. With the exception of the Thames and Severn, the Trent is by far the most important of the rivers of England, on account not only of the length of its course, but of the fertile districts through which it passes, the immense number of canals with which it communicates, and the considerable rivers it receives in its progress.

This fine river has its source near the Cheshire border, in the moorlands of Staffordshire, about four miles north from Burslem. At first its course is nearly south-east, when it makes a sudden turn