DOCK  . established on the See also:

• SEA (in O. Eng. sae, a common Teutonic word; cf. Ger. See, Dutch Zee, &c.; the ultimate source is uncertain)
• SEA, COMMAND OF THE

sea-See also:

• COAST (from Lat. costa, a rib, side)

coast of tideless seas, such as the Mediterranean, on See also:

• ACCOUNT
• ACCOUNT (through O. Fr. acont, Late Lat. comptum, cornputare, to calculate)

account of the See also:

• RIVERS
• RIVERS, ANTHONY WOODVILLE, or WYDEVILLE, 2ND EARL (c. 1442—1483)
• RIVERS, EARL
• RIVERS, RICHARD SAVAGE, 4TH EARL (c. 1660—1712)

rivers being barred by deltas at their outlets, like the See also:

• RHONE
• RHONE (Fr. Rhone, Lat. Rhodanus)

Rhone and the See also:

• TIBER (anc. Tiberis; Ital. Tevere)

Tiber, and thus rendered inaccessible, open basins, provided with quays and protected by as exemplified by the See also:

• SUNDERLAND
• SUNDERLAND, CHARLES SPENCER, 3RD EARL OF (c. 1674-1722)
• SUNDERLAND, ROBERT SPENCER, 2ND EARL OF (1640-17o2); English politician, was the only son of Henry Spencer (162o--1643)

Sunderland docks adjacent to the mouth of the See also:

• RIVER

river See also:

• WEAR

Wear, and the See also:

• HAVRE
• HAVRE, LE

Havre docks at the outlet of the See also:

• SEINE
• SEINE (Lat. Sequana)
• SEINE, or SEAN (O. Fr. seigne, mod. seine, Lat. sagena, Gr. vaytivrl, a draw-net)

Seine See also:

• ESTUARY (from the Lat. aestuarium, a place reached by aestus, the tide)

estuary (fig . 2) . Some old ports, originally established on sandy coasts where a See also:

• CREEK
• CREEK (Mid. Eng. crike or creke, common to many N. European languages)

creek, maintained by the influx and efflux of the See also:

• TIDE (O. Eng. lid, cf. Ger. Zeit, time or season, connected with root of Sanskrit a-diti, endless)

tide from See also:

• LOW, SETH (1850- )
• LOW, WILL HICOK (1853- )

low-lying spaces near the See also:

• SHORE

shore, afforded some shelter and an outlet to the sea across the See also:

• BEACH

beach, have had their See also:

• ACCESS (Lat. accessus)

access improved by parallel jetties and dredging; and docks have been readily formed in the low-lying See also:

• LAND

land only . 355 of. suction dredgers in See also:

• SAND
• SAND, GEORGE (1804-1876)

sand (see DREDGE), together with the increasing See also:

• DRAUGHT (from the common Teutonic word " to draw "; cf. Ger. 7'racht, load; the pronunciation led to the variant form " draft," now confined to certain specific meanings)

draught of vessels, has resulted in a considerable increase being made in the available See also:

• DEPTH

depth of rivers and channels leading to docks, and has necessitated the making of due See also:

• ALLOWANCE (from "allow,' derived through 0. Fr. alouer from the two Lat. origins adlaudare, to praise, and allocare, to assign a place; so that the English word combined the general idea of "assigning with approval")

allowance for the possibility of a reasonable improvement in determining the depth to be given to a new dock . On the other See also:

• HAND
• HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
• HAND, FERDINAND GOTTHELF (1786-185r)

hand, there is a limit to the deepening of an approach channel, depending upon its length, the See also:

• LOCAL

local conditions as regards Fm . 5.-See also:

• PORT

Port of See also:

• MARSEILLES

Marseilles . Basins and Extensions . separated by sand See also:

• DUNES

dunes from the sea, as ,at See also:

• CALAIS

Calais, See also:

• DUNKIRK
• DUNKIRK (Fr. Dunkerque)

Dunkirk (fig . 6) and See also:

• OSTEND (Flemish and French Ostende)

Ostend (see See also:

• HARBOUR (from M.E. hereberge, here, an army; cf. Ger. Heer and -beorg, protection or shelter. Other early forms in English were herberwe and haiborow, as seen in various place names, such as Market Harborough.. The French auberge, an inn, derived through

HARBOUR) . In sheltered places on the sea-coast, docks have sometimes been constructed on low-lying land bordering the shore, with See also:

• DIRECT

direct access to the sea, as at See also:

• BARROW
• BARROW (from A.S. beorh, a mount or hillock)
• BARROW, ISAAC (1630-1677)
• BARROW, SIR JOHN (1764-1848)

Barrow and See also:

• HARTLEPOOL

Hartlepool; whilst at Mediterranean ports open basins have been formed in the sea, by establishing quays along the See also:

• FORESHORE

foreshore, from which wide, solid jetties, lined with See also:

• QUAY
• QUAY, MATTHEW STANLEY (1833-1904)

quay walls, are carried into the sea at intervals: at right angles to the shore, being sheltered by an outlying break- See also:

• WATER

water parallel to the coast, and reached at each end through the openings See also:

• LEFT

left between the projecting jetties and the See also:

• BREAKWATER

breakwater, as at Marseilles (fig. s) and See also:

• TRIESTE (Ger. Triest; Slay. Trst; the Roman Tergeste, q.v.)

Trieste, and at the extensions at See also:

• GENOA (anc. Genua, Ital. Genova, Fr. GPnes)

Genoa (see HARBOUR) and See also:

• NAPLES
• NAPLES (Ital. Napoli, and Lat. Neapolis)
• NAPLES, KINGDOM OF

Naples . Where, however, the basins are formed within the partial See also:

• PROTECTION

protection of a See also:

• BAY

bay, as in the old ports of Genoa and Naples, the requisite additional shelter has been provided by converging breakwaters across the opening of the bay; and an entrance to the port is left between the breakwaters .

The two deep arms of the sea at New See also:

• YORK
• YORK (HOUSE OF)
• YORK, EDMUND OF LANGLEY, DUKE OF (1341-1402)
• YORK, EDWARD
• YORK, FREDERICK AUGUSTUS, DUKE OF (1763-1827)
• YORK, RICHARD, DUKE

York, known as the See also:

• HUDSON
• HUDSON, GEORGE (180o-1871)
• HUDSON, HENRY
• HUDSON, JOHN (1662–1719)

Hudson and See also:

• EAST
• EAST, ALFRED (1849- )

East rivers, are so protected by Staten See also:

• ISLAND (O.E. ieg =isle, +land')

Island and See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

Long Island that it has been only necessary to See also:

• FORM (Lat. forma)

form open basins by, projecting wide jetties or quays into them from the See also:

• WEST
• WEST, BENJAMIN (1738-1820)
• WEST, NICHOLAS (1461-1533)

west and east shores of Manhattan Island, and from the New See also:

• JERSEY
• JERSEY, EARLS OF

Jersey and See also:

• BROOKLYN

Brooklyn shores, at in- tervals, to provide adequate See also:

• ACCOMMODATION (Lat. accommodare, to make fit, from ad, to, cum, with, and modus, measure)

accommodation for See also:

• ATLANTIC

Atlantic liners and the sea-going See also:

• TRADE (O. Eng. trod, footstep, from tredan, to tread; in M. Eng. the forms teed, trod and trade appear, the last in the sense of a beaten track)
• TRADE, BOARD OF

trade of New York . The accessibility of a port depends upon the depth of its approach channel, which also determines the depth of the docks Approach or basins to which it leads; for it is useless to give a chancels. depth to a dock much in excess of the depth down to which there is a prospect of carrying the channel by which it is reached . The See also:

• GREAT

great See also:

• AUGMENTATION

augmentation, however, in the See also:

• POWER [WILLIAM GRATTAN] TYRONE (1797-1841)

power and capacity for See also:

• WORK

work of See also:

• MODERN

modern dredgers, and especially silting, and the resources and prospects of trade of the port, for every addition to the depth generally involves a corresponding increase in the cost of See also:

• MAINTENANCE (Fr. maintenance, from maintenir, to maintain, support, Lat. manu tenere, to hold in the hand)

maintenance . At tidal ports the available depth for vessels should be reckoned from high water of the lowest See also:

• NEAP

neap tides, as the See also:

• STANDARD
• STANDARD, BATTLE OF THE

standard which is certain to be reached at high tide; and the See also:

• PERIOD
• PERIOD (Gr. irepioSos, a going or way round, circuit, aepi, round, and &Sis, way, road)

period during which docks can be entered at each tide depends upon the nature of the approach channel, the extent of the tidal range and the manner in which the entrance to the docks is effected . Thus where the tidal range is very large, as in the See also:

• SEVERN
• SEVERN, JOSEPH (1793-1879)

Severn estuary, the approach channels to some of the See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

South See also:

• WALES (Cymru, Gwalia, Cambria)

Wales ports are nearly dry at low water of See also:

• SPRING (from " to spring," " to leap or jump up," " burst out," O. Eng., springau, a common Teut. word, cf. Ger. springer, possibly allied to Gr. QnrFpxecOac, to move rapidly)

spring tides, and it would be impossible to make these ports accessible near low tide; whereas at high water, even of neap tides, vessels of large draught can enter their docks . At See also:

• LIVERPOOL
• LIVERPOOL, EARLS
• LIVERPOOL, EARLS OF

Liverpool, with a rise of 31 ft. at equinoctial spring tides, owing to the deep channel between Liverpool and See also:

• BIRKENHEAD

Birkenhead and into the See also:

• OUTER

outer estuary of the See also:

• MERSEY

Mersey iri Liverpool a W N x 0 z Bay, maintained by the powerful tidal scour resulting from the filling and emptying of the large inner estuary, access to the river by the largest vessels has been rendered possible, at any See also:

• STATE
• STATE, GREAT OFFICERS OF

state of the tide, by dredging a channel through the Mersey See also:

• BAR
• BAR (0. Fr. barre, Late Lat. barra, origin unknown)
• BAR, CONFEDERATION OF
• BAR, FRANCOIS DE (1538-1606)
• BAR, THE

bar; but the docks cannot be entered till the water has risen above See also:

• HALF

half-tide level, and the See also:

• GATES, HORATIO (1728-1806)

gates are closed directly after high water . A large floating landing-See also:

• STAGE (Fr. 6/age; from Lat. stare, to stand)

stage, however, about half a mile in length, in front of the centre of the docks, connected with the shore by several hinged See also:

• BRIDGES
• BRIDGES, ROBERT (1844– )

bridges and rising and falling with the tide, enables Atlantic liners to come alongside and take on See also:

• BOARD (O. Eng. bord)

board or disembark their passengers at any See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time . Comparatively small tidal rivers offer the best opportunity of a considerable See also:

• IM(K2+a2+h2—2 ah cos 0)

im- provement in the approach channel to a port; for they can be converted into artificially deep channels by dredging, and their necessary maintenance is somewhat aided by the increased influx and efflux of tidal water due to the lowering of the low-water See also:

• LINE

line by the outflow of the ebb tide being facili- tated by the deepening . Thus systematic, continuous dredging -:::enl'Tot . CHANNEL.- in the See also:

• TYNE

Tyne and the 'See also:

• CLYDE (Welsh, Clwyd, " far heard," " strong," the Glotta of Tacitus)
• CLYDE, COLIN CAMPBELL, BARON (1792-1863)

Clyde has raised the Tyne ports and See also:

• GLASGOW

Glasgow into first-class ports . In large tidal rivers and estuaries, docks should be placed alongside a See also:

• CONCAVE

concave See also:

• BANK

bank which the deep navigable channel hugs, as effected at See also:

• HULL
• HULL (in O.Eng. hulu, from helan, to cover, cf. Ger. Hiille, covering)
• HULL (officially KINGSTON-UPON-HULL)
• HULL, ISAAC (1775-1843)

Hull and See also:

• ANTWERP
• ANTWERP (Fr. Anvers)

Antwerp, or dose to a permanently deep channel in an estuary, such as chosen for See also:

• GARSTON

Garston and the entrance to the See also:

• MANCHESTER
• MANCHESTER (popularly Manchester-by-the-Sea)
• MANCHESTER, EARLS AND DUKES OF

Manchester See also:

• SHIP

ship See also:

• CANAL
• CANAL (from Lat. canalis, " channel " and " kennel " being doublets of the word)

canal at Eastham in the inner Mersey estuary, and for See also:

• GRIMSBY, or GREAT GRIMSBY

Grimsby and the authorized Illingham dock in the See also:

• HUMBER

Humber estuary; for a channel carried across an estuary to deep water requires See also:

• CONSTANT, BENJAMIN (1845-1902)

constant dredging to maintain its depth . Occasionally, extensive draining See also:

• WORKS

works and dredging have to be executed to form an adequately deep channel through a shifting estuary and shallow river to a port, as for instance on the See also:

• WESER (O. Ger. Visuracha, Wisura, Lat. Visurgis)

Weser to See also:

• BREMERHAVEN

Bremerhaven and See also:

• BREMEN

Bremen, on the Seine to See also:

• HONFLEUR

Honfleur and See also:

• ROUEN

Rouen, on the See also:

• TEES

Tees to Middlesborough and See also:

• STOCKTON
• STOCKTON, FRANCIS RICHARD (1834–1902)

Stockton, on the Ribble to See also:

• PRESTON
• PRESTON, JOHN (1587-1628)

Preston, on the See also:

• MAAS, JOSEPH (1847-1886)

Maas to See also:

• ROTTERDAM

Rotterdam and on the Nervion to See also:

• BILBAO

Bilbao (see RIvER See also:

• ENGINEERING

ENGINEERING) .

See also:

• SOUTHAMPTON
• SOUTHAMPTON, EARL OF
• SOUTHAMPTON, HENRY WRIOTHESLEY, 3RD EARL OF (1J73—1624)

Southampton possesses the very rare See also:

• COMBINATION (Lat. combinare, to combine)

combination of advantages of a well-sheltered and fairly deep estuary, a rise of only 12 ft. at spring tides, and a position at the See also:

• HEAD (in 0. Eng. heafad; the word is common to Teutonic languages; cf. Dutch hoofd, Ger. Haupt, generally taken to be in origin connected with Lat. caput, Gr. KerbOvi7)
• HEAD, SIR EDMUND WALKER, BART
• HEAD, SIR FRANCIS BOND, BART

head of Southampton Water at the confluence of two rivers (fig . 4), so that, with a moderate amount of dredging and the construction of quays along the See also:

• LOWER

lower ends of the river with a depth of 35 ft. in front of them at low water, it is possible for vessels of the largest draught to come alongside or leave the quays at any state of the tide . This circumstance has enabled Southampton to attract some of the Atlantic steamers formerly See also:

• RUNNING

running to Liverpool . Ports on tideless seas have to be placed where deep water approaches the shore, and where there is an See also:

• ABSENCE (Lat. absentia)

absence of littoral See also:

• DRIFT (from "drive ")

drift . The basins of such ports are always accessible for vessels of the draught they provide for; but they require most efficient protection, and, unlike tidal ports, they are not able to exceptional occasions to admit a See also:

• VESSEL (O. Fr. vaissel, from a rare Lat. vascellum, dim. of vas, vase, urn)

vessel of larger draught than the basins have been formed to accommodate . Occasionally, an old port whose approach channel has become inadequate for modern vessels, or from which the sea has receded, has been provided with deep access from the sea by a ship canal, as exemplified by See also:

• AMSTERDAM
• AMSTERDAM (NEw AMSTERDAM)

Amsterdam and See also:

• BRUGES (Flemish Brugge, a name signifying the bridge or place of bridges)

Bruges; whilst Manchester has become a sea-port by similar works (see MANCHESTER SHIP CANAL) . In such cases, however, perfectly sheltered open basins are formed inland at the head of the ship canal, in the most convenient available site; and the See also:

• SIZE

size of vessels that can use the port depends wholly on the dimensions and facility of access of the ship canal . Docks require to be so designed that they may provide the maximum length of quays in proportion to the water See also:

• AREA

area consistent with easy access for vessels to the quays; but often the space available does not admit of the See also:

• ADOPTION (Lat. adoptio, for adoptalio, from adoptare, to choose for oneself)

adoption of the best forms, and the See also:

• DESIGN (Fr. desiin, drawing; Lat. designare, to mark out)

design has Design of to be made as suitable as practi- Doffs. See also:

• CABLE (from Late Lat. capulum, a halter, from capere, to take hold of)
• CABLE, GEORGE WASHINGTON (1844– )

cable under the existing conditions . On this account, and owing to the small size of vessels in former times, the docks of old ports See also:

• PRESENT

present a great variety in size and arrangement, being for the most See also:

• PART

part narrow and small, forming a sort of See also:

• STRING

string of docks communicating with one another, and See also:

• PRO

pro- vided with locks or entrances at suitable points for their See also:

• COMMON

common use, as noticeable in the older See also:

• LONDON

London and Liverpool docks . Though narrow See also:

• TIMBER

timber jetties were introduced in some of the wider London docks for in- creasing the length of quays by placing vessels alongside them, no definite arrange- ment of docks was adopted in carrying out the large See also:

• VICTORIA
• VICTORIA (or VITTORIA), TOMMASSO LUDOVICO DA (C. I540-C. 1613)
• VICTORIA [ALEXANDRINA VICTORIA]

Victoria and See also:

• ALBERT
• ALBERT (1490'1545)
• ALBERT (149o-1568)
• ALBERT (1522–1557)
• ALBERT (FRANCIS CHARLES AUGUSTUS ALBERT EMMANUEL) (1819—1861)
• ALBERT (FRIEDRICH RUDOLF ALBRECHT)
• ALBERT, FREDERICK AUGUSTUS
• ALBERT, MADAME (c. 2805—2846)

Albert docks between 185o and 188o; whilst the Victoria dock was made wide with solid quays, provided with warehouses, projecting from the See also:

• NORTHERN

northern quay See also:

• WALL (O. Eng. weal, weall, Mid. Eng. wal, wane, adapted from Lat. vallum, rampart; the original O. Eng. word for a wall was wag or tenth)
• WALL, RICHARD (1694-1778)

wall, thereby affording a large accom- modation for vessels lying end on to the See also:

• NORTH
• NORTH, BARONS
• NORTH, MARIANNE (1830—1890)
• NORTH, ROGER (1653-1734)
• NORTH, SIR THOMAS (1535?-16o1?)

north quay, the Albert dock subsequently constructed was given about half the width of the earlier dock, but made much longer, so that vessels See also:

• LIE, JONAS LAURITZ EDEMIL (1833—1908)
• LIE, MARIUS SOPHUS (1842–1899)

lie alongside the north and south quays in a long line . This See also:

• CHANGE (derived through the Fr. from the Late Lat. cambium, cambiare, to barter; the ultimate derivation is probably from the root which appears in the Gr. «a urmu', to bend)

change of form, however, was probably dictated by the See also:

• ADVANTAGE

advantage of stretching across the See also:

• REMAINDER, REVERSION

remainder of the wide See also:

• BEND

bend, in See also:

• ORDER
• ORDER (through Fr. ordre, for earlier ordene, from Lat. ordo, ordinis, rank, service, arrangement; the ultimate source is generally taken to be the root seen in Lat. oriri, rise, arise, begin; cf. " origin ")
• ORDER, HOLY

order to obtain a second entrance in a lower reach of the river . The Tilbury docks, the latest and lowest docks on the See also:

• THAMES

Thames, were constructed on the most approved modern See also:

• SYSTEM

system, consisting of a See also:

• SERIES (a Latin word from serere, to join)

series of See also:

• BRANCH (from the Fr. branche, late Lat. branca, an animal's paw)

branch docks separated by wide, well-equipped solid quays, and opening straight into a See also:

• MAIN (from the Aryan root which appears in " may " and " might," and Lat. magnus, great)
• MAIN (Lat. Moenus)

main dock or See also:

• BASIN, or BASON (the older form bacin is found in many of the Romanic languages, from the Late Lat. baccinus or bacchinus, probably derived from bacca, a bowl)
• BASIN, THOMAS (1412—1491)

basin communicating with the entrance See also:

• LOCK (from the O. Eng. loc.; the word appears, in different forms, in many Teutonic languages, but with such various meanings as " hole," Ger. Loch, " lid," Swed. lock, &c.; probably the original was a root meaning " to enclose ")
• LOCK, MATTHIAS

lock, in which vessels can turn on entering or leaving the docks (fig .

7) . The most recently constructed Liverpool docks, also, at the northern end have been given this form ; and the older docks adjoining them to the south have been transformed by reconstruction into a similar series of branch docks opening into a dock alongside the river wall, leading to a half-tide basin or river entrances (fig . I) . The Manchester and See also:

• SALFORD

Salford docks were laid out on a precisely similar system, which was also adopted for the most See also:

• RECENT

recent docks at Dunkirk (fig . 6) and See also:

• PRINCE
• PRINCE (Lat. princeps, from primus capio, " I am the first to take "; Ital. principe, Fr. prince)

Prince's dock at Glasgow (fig . 3), and at some of the See also:

• PRINCIPAL

principal See also:

• RHINE (Lat. Rhenus, Ger. Rhein, Fr. Rhin, Dutch Rhyn, or Rijn)

Rhine ports; whilst the Alexandra dock at Hull resembles it in principle . The basins in tideless seas have naturally been long formed in accordance with this system (fig . 5) . The See also:

• BARRY
• BARRY, ELIZABETH (1658—1713)
• BARRY, JAMES (1741—1806)
• BARRY, SIR CHARLES (1795-1860)
• BARRY, SIR REDMOND (1813-188o)
• BARRY, SPRANGER (1719-1777)

Barry docks furnish an example of the See also:

• SPECIAL

special arrangements for a See also:

• COAL

coal-See also:

• SHIPPING

shipping port, with numerous coal-tips served by sidings (fig . 8idal basins, as they are termed, are generally interposed in the docks of London between the entrance locks and the docks, with the Tideland See also:

• OBJECT

object of facilitating the passage of vessels out of and into Ti the docks before and after high water, by lowering the half-Me water in the basin as soon as the tide has risen sufficiently, basins. and opening the lock gates directly a level has been formed with the tide in the river . Then the vessels which have collected in the basin, when level with the dock, are readily passed successively into the river . The incoming vessels are next brought into the basin, and the gates are closed; and the water in the basin having been raised to the level in the dock, the gates shutting off the basin from the dock when the water was lowered are opened, and the vessels are admitted to the dock .

In this manner, by meansof an inner pair of gates, the basin can be used as a large lock without unduly altering the water-level in the dock, and saves the delay of locking most of the vessels out and in, the lock being only used for the smaller vessels leaving See also:

• EARLY
• EARLY, JUBAL ANDERSON (1816-1894)

early or coming in See also:

• LATE

late on the tide . Similar tidal basins have also been provided at See also:

• CARDIFF

Cardiff,See also:

• PENARTH

Penarth, Barry (fig . 8), Sunderland, Antwerp and other docks . The large half-tide docks introduced at the most modern Liverpool docks (fig. i) serve a similar purpose as tidal basins; but being much larger, and approached by entrances instead of locks, the exit and entrance of vessels are effected by lowering their water-level on a rising tide, and opening the gates, which are then closed at high water to prevent the lowering of the water-level in the dock, and to avoid closing the gates against a strong issuing current: The tidal basins outside the locks at Tilbury and Barry are quite open to the tide, and have been carried down to 24 ft. and 16 ft. respectively below low water of spring tides, in order to afford vessels a deep sheltered approach to the lock in each See also:

• CASE
• CASE, JOHN (d. 1600)

case, available at or near low water (See also:

• FIGS

figs . 7 and 8) . Such basins, however, open to a considerable tidal range where the water is densely charged with silt, are exposed to a large See also:

• DEPOSIT (Lat. depositurn, from deponere, to lay down, to put in the care of)

deposit in the fairly still water, and their depth has to be constantly maintained by sluicing or dredging . Where the range of tide is moderate, or on large inland rivers, docks or basins are usefully supplemented by river quays, which River though subject to changes in the water-level, and exposed to currents in the river, are very convenient for access, quays. and are sometimes very advantageously employed in regulating a river and keeping up its See also:

• BANKS, GEORGE LINNAEUS (1821-1881)
• BANKS, NATHANIEL PRENTISS (1816–1894)
• BANKS, SIR JOSEPH
• BANKS, THOMAS (1735-1805)

banks when deepened by dredging . Generally to to 12 ft. is the limit of the tidal range convenient for the adoption of open basins and river quays; but the banks of the Tyne have been utilized for quays, jetties and coalstaiths, with a somewhat larger maximum tidal range; and a long line of quays stretching along the right bank of the See also:

• SCHELDT (Fr. Escaut, Flem. Schelde)

Scheldt in front of Antwerp, constructed so as to regulate this reach of the river, accommodates a large sea-going See also:

• TRAFFIC

traffic, with a rise at spring tides of 15 ft . When a dock has to be formed on land, the excavation is effected by men with barrows and powerful See also:

• STEAM
• STEAM (0. Eng. steam, vapour, smoke, cf. Du. steam; the origin is unknown)

steam navvies, loading into wagons See also:

• DRAWN

drawn in trains by locomotives to the See also:

• PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)

place of Excava- deposit, usually to raise the land at the sides for forming floes for quays . Directly the underground water-level is reached, docks. the water has to be removed from the excavations by pumps raising the inflowing water from sumps, lined with timber, sunk down below the lowest See also:

• FOUNDATIONS

foundations at suitable positions, so that the lower portions of the dock walls and sills of the lock or entrance maybe built out of water . A See also:

• COFFERDAM

cofferdam has to be constructed extending out from the bank of the river or approach channel in front of the site of the proposed entrance or lock, so that the excavations for the entrance to the dock may be pushed forwards, and the lock or entrance built under its protection . Sometimes the lowest portion of the excavation for the dock can be accomplished economically by dredging, after the dock walls and lock have been completed and the water admitted .

Where a dock is partially or wholly constructed on reclaimed land, the reclamation bank for enclosing the site and excluding the tide has to be undertaken first by tipping an See also:

• EMBANKMENT

embankment from each end with wagons, protected and consolidated along its outer toe by See also:

• RUBBLE

rubble See also:

• STONE
• STONE (0. Eng. shin; the word is common to Teutonic languages, cf. Ger. Stein, Du. steen, Dan. and Swed. sten; the root is also seen in Gr. aria, pebble)
• STONE, CHARLES POMEROY (1824-1887)
• STONE, EDWARD JAMES (1831-1897)
• STONE, FRANK (1800-1859)
• STONE, GEORGE (1708—1764)
• STONE, LUCY [BLACKWELL] (1818-1893)
• STONE, MARCUS (184o— )
• STONE, NICHOLAS (1586-1647)

stone or See also:

• CHALK

chalk . When the ends of the embankments are approaching one another, it is essential to connect them by a long low bank of selected materials brought up gradually in successive layers, and retaining the water in the enclosure to the level of this bank, so that the influx and efflux of the tide, filling and emptying the reclaimed area, may take place over a long length, and in smaller See also:

• VOLUME

volume as the low bank is raised . In this way a reduction is effected of the tidal current in and out, which in the case of a large enclosure and a considerable tidal range, would create such a scour in the narrowing See also:

• GAP

gap between two high embankments as to See also:

• WASH, THE

wash away their ends and prevent the closing of the gap . Occasionally the final See also:

• CLOSURE (Fr. clooture)

closure is effected by lowering timber panels in grooves betweena series of piles driven down at intervals across the gap . On the closing of the reclamation bank the water is pumped out; and the excavation is carried on in the See also:

• ORDINARY (med. Lat. ordinarius, Fr. ordinaire)

ordinary manner . It is very, important that such an embankment should be carried well above the level of the highest tide which might be raised by a high See also:

• WIND
• WIND (a common Teut. word, cognate with Skt. vats, Lat. ventus, cf. " weather," to be of course distinguished from to " wind," to coil or twist, O.Eng. windan, cf. "wander," "wend," &c.)

wind; and in exposed sites, the outer slope of the bank should be protected by pitching from the See also:

• ACTION

action of waves, for any overtopping or erosion of the bank might result in a large See also:

• BREACH (Mid. Eng. breche, derived from the common Teutonic root brec, which appears in " break," Ger. brechen, &c.)

breach through it, and the flooding of the works inside . Docks are generally surrounded by walls retaining the quays, alongside which vessels lie for discharging and taking in cargoes . In order to ascertain the nature of the strata upon which these walls have to be founded, borings are taken at the Fouadaoutset to the requisite depth at intervals near the line flops for of the walls, but inside the dock area if the piercing of dock walls. quicksand is anticipated, as in excavating for the foundations, these holes might give rise to the outflow, under pressure, of underlying quicksand into the foundations . As docks are generally formed near rivers or estuaries, these strata are commonly alluvial; but being situated at some depth below the See also:

• SURFACE

surface, they are usually fairly hard . When they consist of See also:

• GRAVEL, or PEBBLE BEDS

gravel, See also:

• CLAY (from O. Eng. claeg, a word common in various forms to Teutonic languages, cf. Ger. Klei)
• CLAY, CASSIUS MARCELLUS (1810-1903)
• CLAY, CHARLES (1801–1893)
• CLAY, FREDERIC (1838–1889)
• CLAY, HENRY (1777–1852)

clay or See also:

• FIRM

firm sand, the walls can be founded on the natural bottom excavated a few feet below the bottom of the dock, their See also:

• WEIGHT

weight being somewhat distributed by making them See also:

• REST (O. Eng. rest, reste, bed, cognate with other Teutonic forms, e.g. Ger. Rast, Riiste, rest, and probably Gothic Rasta, league, i.e. resting or stopping place)

rest on a broad See also:

• BED
• BED (a common Teutonic word, cf. German Bett, probably connected with the Indo-European root bhodh, seen in the Lat. fodere, to dig; so " a dug-out place " for safe resting, or in the same sense as a garden " bed ")

bed of See also:

• CONCRETE
• CONCRETE (Lat. concretes, participle of concrescere, to grow together)

concrete filling up the excavation at the bottom . When, however, See also:

• FINE

fine sand or silt charged with water, or quicksand is met with at the required depth, the necessary pumping and excavation for the foundations might occasion the influx of sand or silt with the water into the excavations, leading to See also:

• SETTLEMENT
• SETTLEMENT, ACT OF

settlement and slips; or the soft stratum might be too thick to remove . The wall may then be founded on bearing piles driven down to a solid stratum, and having their tops joined together by walings and planking, or by a layer of concrete, upon which the wall is built .

Or the soft stratum can be enclosed with a See also:

• DOUBLE
• DOUBLE (from the Mid. Eng. duble, the form which gives the present pronunciation, through the Old Er. duble, from Lat. duplus, twice as much)

double See also:

• ROW, JOHN (c. 1525—1580)

row of See also:

• SHEET

sheet piling along the front and back of the line of wall, by which it sometimes becomes sufficiently confined and consolidated to sustain the weight of the wall on a broad See also:

• FOUNDATION (Lat. fundatio, from fundare, to found)

foundation of concrete; or it can be excavated without any danger of sand or silt running in from outside; whilst the sheet piling at the back relieves the wall to some extent from the pressure of the See also:

• EARTH
• EARTH (a word common to Teutonic languages, cf. Ger. Erde, Dutch aarde, Swed. and Dan. jord; outside Teutonic it appears only in the Gr. 'pq'e, on the ground; it has been connected by some etymologists with the Aryan root ar-, to plough, which is seen in
• EARTH, FIGURE OF
• EARTH, FIGURE OF THE

earth behind it, and in front retains the wall from sliding forwards . Firmer foundations have been obtained by sinking See also:

• BRICK (derived according to some etymologists from the Teutonic bricke, a disk or plate; but more authoritatively, through the French brique, originally a " broken piece," applied especially to bread, and so to clay, from the Teutonic brikan, to break)

brick, concrete or See also:

• MASONRY

masonry See also:

• WELLS
• WELLS, CHARLES JEREMIAH (1798?–1879)
• WELLS, DAVID AMES (1828—1898)
• WELLS, HERBERT GEORGE (1866— )
• WELLS, SIR THOMAS SPENCER, 1ST BART

wells through soft ground to a solid stratum, upon which the dock wall is built . Clusters of small concrete cylinders, in sets of three in front, and a line of double cylinders at the back, were used for the foundations of the walls of Prince's dock at Glasgow . Wells of rubble masonry were sunk in the silty fore-shore of the Seine estuary for the walls of the See also:

• BELLOT, JOSEPH RENE (1826–1853)

Bellot docks at Havre; and they served as piers, connected by See also:

• ARCHES, COURT OF

arches, for the foundations of a continuous dock wall above, being carried down to a considerable depth through See also:

• ALLUVIUM

alluvium at the St Nazaire, See also:

• BORDEAUX

Bordeaux and See also:

• ROCHEFORT
• ROCHEFORT, HENRI, MARQUIS DE

Rochefort docks . These well foundations, derived from the old See also:

• INDIAN

Indian system, are built up upon a curb, sometimes furnished with a cutting edge underneath, and gradually sunk by excavating inside; and eventually the central hollow is filled up solid with concrete or masonry . The walls See also:

• ROUND (O. Fr. rond, Lat. rotundus, the Fr. is the source also of Du. rond; Ger., Swed., Dan. and Nor. rond)

round a dock serve as retaining walls to keep up the quays; and though they have the support of the water in front of them when the docks are in use, they have to sustain the full pressure of the filling at the back on the completion of the dock before the water is admitted . They have, accordingly, to be increased in thickness downwards to support the pressure increasing Dock with the depth . This pressure, with perfectly dry material, Dot* would be represented by the weight of half the See also:

• PRISM (Gr. rrpivµa, properly a thing sawn, Irpii"ety, to saw)

prism of filling between the natural slope of the material behind and the back of the wall ; but the pressure is often increased by the See also:

• ACCUMULATION (from Lat. accumulare, to heap up)

accumulation of water at the back, which, with fine silty backing, is liable to exert a sort of fluid pressure against the wall proportionate to the See also:

• DENSITY (Lat. densus, thick)

density of the mixture of silt and water . The increase of thickness towards the See also:

• BASE

base used formerly to be effected by a See also:

• BATTER

batter on the See also:

• FACE (from Lat. fades, derived either from facere, to make, or from a root fa-, meaning " appear "; cf. Gr. cbatvstv)

face, as well as by steps out at the back; but the See also:

• VERTICAL (from Lat. vertex, highest point)

vertical form now given to the sides of large vessels necessitates a corresponding fairly vertical face for the wall, to prevent the upper part of the vessel being kept unduly away from the quay . Examples of the most modern types of dock walls are given in figs . 9 to 12 . The height of a dock wall depends upon the depth of water always available for vessels, at tideless sea-ports and at ports removed from tidal influences, such as Manchester, Bruges and the ports on the Rhine ; this depth should not be less than 28 to 30 ft. for large sea-going vessels, together with a margin of 5 to 8 ft. above the normal water-level for the quays, and the foundations below .

At tidal ports, however, an addition has to be made equal to the difference in height between the high-water levels of spring and neap tides; so that at ports with a large tidal range, such as the South Wales ports on the Severn estuary and Liverpool, specially high dock walls are necessary . Under normal conditions, a dock wall should Dock Wall . be given a width at a height half-way between dock-bottom and quay-level', equal to one-third of its height above dock-bottom, and a width of half this height at dock-bottom . Dock walls are constructed of masonry, See also:

• BRICKWORK

brickwork or concrete, or of concrete with a facing of masonry or brickwork . Masonry is adopted where large stone quarries are readily accessible, in the form of rubble masonry with dressed stone on the face, as for instance at ~.7 the Hull and Barry docks, and forms a very durable wall; but strong overhead staging i-• carrying powerful gantries is necessary for { laying large blocks . Brickwork has been often used where bricks are the ordinary See also:

• BUILDING

building material of the See also:

• DISTRICT

district or can be made on the ,l works, and requires only ordinary scaffolding; 1 and harder or pressed bricks are employed for the facework . Concrete is very commonly resorted to now where sand and stones are ; readily procured; and where clean, See also:

• SHARP, GRANVILLE (1735-1813)
• SHARP, JAMES (1618-1679)
• SHARP, JOHN (1645-1714)
• SHARP, RICHARD (1759-1835)
• SHARP, WILLIAM (1749-1824)
• SHARP, WILLIAM (1856-1905)

sharp ` sand and gravel are found in thick layers in the excavations for a dock, aasin the alluvial strata bordering the Thames, dock walls can FIG . 1o.—Liverpool be constructed cheaply and economically with Dock Wall. concrete deposited within timber framing, dispensing with See also:

• REGULAR

regular scaffolding and skilled . labour . Such walls require to be given a facing of stronger See also:

• CON

con- See also:

• CRETE (Gr. Kp;rrrr; Turk. Kirid, Ital. Candia)

crete, or of See also:

• BLUE (common in different forms to most European languages)

blue bricks, as at Tilbury, to guard against See also:

• ABRASION (from Lat. ab, off, and radere, to scrape)

abrasion by vessels, chains and See also:

• ROPES, JOHN CODMAN (1836–1899)

ropes; and dock walls are commonly pro- vided at the See also:

• TOP (cf. Dan. top, Ger. Topf, also meaning pot)

top with See also:

• GRANITE (adapted from the Ital. granite, grained; Lat. granum, grain)

granite or other hard stone See also:

• COPING (from " cope," Lat. capa)

coping where the wear is greatest . The foundations for dock walls are excavated in a See also:

• TRENCH, RICHARD CHENEVIX (1807-1886)

trench below dock-bottom, only lined with timbering where the faces of the trench cannot stand for a See also:

• SHORT, FRANCIS JOB (1857– )

short time without support, and with sheet piling through very unstable silt or sand; and the trench is conveniently filled up solid . with concrete,carried out in short lengths in untrustworthy ground .

To reduce the amount of filling behind the wall,thc+ excavation at the back above dock bottom, preparatory for the trench, is given as steep a slope as practicable, supported sometimes towards the base by timbering and struts; but occasion- ally the wall is built within a timbered trench carried down to the required depth, before the excavation for the dock in front of it has been executed; as effected at Tilbury . The filling at the back is thus reduced to a minimum, and the lower portion of the excavation can Wall. ent, after the See also:

• ADMISSION

admission of the water, the dock wall in this way being exposed totheleast possible pressure behind . The walls of open basins are often constructed out of water precisely like dock walls, as in the case of the basins forming the Manchester, Bruges and Glasgow docks; and basin walls open to the tide, as at Glasgow and in the tidal basin outside Tilbury docks (fig . 7), differ only from dock :6 -c• walls in being exposed to See also:

• VARIATIONS
• VARIATIONS, CALCULUS
• VARIATIONS, CALCULUS OF

variations i wosx' ~~~~ c _.__-;_~'•~'~ in the pressure at the back resulting from the lowering of the water-level in front, which is, indeed, shared to some extent by the walls round closed docks where the difference in the high- ! water levels of springs and neaps 1—= is considerable . The walls, however, round basins in tideless seas, such as _ Marseilles, occasionally those inside _\ harbours, and especially quay walls alongsidrivers and round e rivers, have to be constructed — under water . ' At Marseilles, the See also:

• SIMPLE

simple expedient was long ago adopted of constructing the quay walls lining the basins formed Wall. concrete blocks on a rubble foundation, one on top of the other, till they reached sea-level, and then building a solid masonry quay wall Open basin out of water on the top up to quay-level, faced with See also:

• ASHLAR

ashlar and river behind)up to the water-level. bThe rubble system was em quay wails ployed for the quay walls at' Trieste, and at Genoa and founded other See also:

• ITALIAN

Italian ports . A quay wall inside Marmagao har- under See also:

• HOUR

hour, on the west coast of See also:

• INDIA
• INDIA, FRENCH

India, was erected on a founda- water. tion layer of rubble by the sloping-See also:

• BLOCK
• BLOCK (from the Fr. bloc, and possibly connected with an Old Ger. Block, obstruction, cf. " baulk ")
• BLOCK, MAURICE (1816–19or)

block system, to provide against unequal settlement on the soft bottom (see BREAK-WATER) . The quay walls alongside the river Liffey, and round the adjacent basins below See also:

• DUBLIN

Dublin, were erected under water by building rubble-concrete blocks of . 36o tons on staging carried out into the water, from which they were lifted one by one by a powerful floating See also:

• DERRICK

derrick, which conveyed the block to the site, and deposited it on a levelled bottom at low tide in a depth of 28 ft.; raising the wall a little above low water . After a row of these blocks had been laid, and connected together by filling the grooves formed at the sides and the interstices between the blocks with concrete, a continuous masonry wall faced with ashlar was built on the top out of water . A quay wall was built up to a little above low water on a similar principle at See also:

• CORK
• CORK (perhaps through Sp. corcha from Lat. cortex, bark, but possibly connected with quercus, oak)
• CORK, RICHARD BOYLE

Cork, with three smaller blocks as a foundation; in lengths. of 8 ft . Cylindrical well foundations have been extensively used for the foundations of the quay walls along the Clyde, formerly made of brick, but subsequently of concrete, sunk through a considerable, variety of alluvial strata, but mostly sand and gravel fully charged with water .

Compressed See also:

• AIR (from an Indo-European root meaning " breathe," " blow ")
• AIR, or ASBEN

air in bottomless caissons has been increasingly employed in recent years for carrying down the," subaqueous founda tions of river quay walls, through alluvial deposits, to a solid stratum . About 1880, a long — line of river quays — was commenced in front of Antwerp, extending in the central portion a considerable distance out into the Scheldt, with the object of regulating the width of the river simultaneously with the See also:

• PROVISION (Lat. provisio)

provision FIG.' 14.—Antwerp Quay Wall, founded by of deep quays for compressed air. sea-going vessels; and the quay wall was erected, out of water, on the See also:

• FLAT (a modification of O. Eng. flet, an obsolete word of Teutonic origin, meaning the ground beneath the feet)

flat tops of a , series of wrought-See also:

• IRON [symbol Fe, atomic weight 55.85 (0=16)]

iron caissons, 82 ft. long and 29 ft. wide, constructed on shore, floated out one by one to their site in the river between two See also:

• BARGES

barges, and gradually lowered as the wall was built up inside a See also:

• PLATE

plate-iron enclosure round the roof of the See also:

• CAISSON (from the Fr. caisse, the variant form " cassoon " being adapted from the Ital. casone)

caisson, which was eventually sunk by aid of compressed air through the bed of the river to a compact stratum (fig . 14)• . The weight of the wall counteracted the tendency of the caisson and the enclosure above it to See also:

• FLOAT (in O. Eng. floc and flota, in the verbal form f eotan; the Teutonic root is flut-, another form of flu-, seen in " flow," cf. " fleet "; the root is seen in Gr. a-M e, to sail, Lat. pluere, to rain; the Lat, fluere and fluctus, wave, is not connect

float; and the caisson, furnished with seven circular wrought -iron shafts, provided with air-locks at the top for the ad-See also:

• MISSION

mission of men and materials and for the removal of the excavations, was gradually carried down by ex- cavating inside the Genoa. working chamber at the bottom, 64 ft. high, till a See also:

• GOOD, JOHN MASON (1764-1827)

good foundation was reached . The, working chamber was then filled with concrete through some of the shafts, the plate-iron sides of the upper enclosure were removed to be used for another length of wall, the shafts were drawn out and the hollows left by them filled with concrete, the apertures between adjacent lengths were closed at each face with wooden panels and filled with concrete, and a continuous quay wall was completed above . The most recent quay walls constructed in the old harbour, -- .~ r IAS SHALE . at Genoa were founded under water on a rubble See also:

• MOUND

mound in a similar manner by the aid of compressed air (fig . 15) . Quay walls also on the Clyde have been founded on caissons, consisting of a bottom-less See also:

• STEEL, FLORA ANNIE (1847– )

steel structure, surmounted by a brick superstructure having hollows filled with concrete, in lengths of 8o ft. and 27 ft., and widths of 18 ft. and 21 ft. respectively, carried down by means of compressed air from 54 to 70 ft. below quay-level, on the top of which a continuous wall of concrete, faced with brickwork, and having a = granite coping, j was built up from ra+asr . ; = een~uNC wirM near low-water level (fig . 16) . In .asr = Q`- 'Y many cases where / soft strata extend to considerable depths, river ~i 'o quays and basin walls have been n > - constructed by building a See also:

• LIGHT

light series of wall bearing a and raking piles driven into, and if possible aum .

Thus the walls along the Seine, and round the basins at Rouen, were built upon bearing piles carried down through the alluvial bed of the river to the chalk . The lower portion of the quay wall was constructed of concrete faced with brickwork within water-tight timber caissons, resting upon the piles at a depth of 91 ft. below low water; and upon this a rubble wall faced with bricks was erected from low water to quay-level, backed by rubble stone laid on a timber flooring sup-ported by piles, together with chalk, to form a quay right back to the top of the slope of the bank of the deepened river (fig . 17) . The quay walls of the open basins bordering the t Hudson river at New w o T . `.:~',~~!y1~e~~~-~~r,-g.~a.i York have had, in cer- See also:

• TAIN

tain parts, to be founded o'"~~ ::' =~ `"'' ^"'~:~:'•a ;~ on bearing piles com- . bined with raking piles, • ;J ~I~ $911 • ! - driven into a thick bed le.ln of soft silt where no firm 2n : stratum could be reached, ~ and where, therefore, the weight could only be . ~.' See also:

• BORNE, KARL LUDWIG (1786–1837)

borne by the adherence of the long piles in the f`' silt . Before See also:

• DRIVING (from " to drive," i.e. generally to propel, force along or in, a word common in various forms to the Teutonic languages)

driving the piles, however, the silt ;-z: round the upper part of the piles and under the chpuc . •' quay wall was consoli- dated by depositing small stones in a trench dredged to a depth of 30 ft. below low water; the piles were driven through these stones, and were further kept in place by a long toe of rubble stone in front and a backing of rubble stone behind carried nearly up to quay-level, behind which a light filling of ashes and earth was raised to quay-level . The slight quay wall resting upon the front rows of bearing piles was carried up under water by 7o-ton concrete blocks deposited by means of a floating derrick; and the upper part of the wall was built of concrete faced with ashlar masonry (fig . 18) . The basin and quay walls at Bremen, Bremerhaven and See also:

• HAMBURG

Hamburg were built on a series of bearing and raking piles driven down to a firm stratum, the wall being begun a few feet below low water .

At Southampton, ferro-concrete piles were employed in constructing the deep quays; and a wharfing of timber pilework has been frequently used for river quays . Where the increase of trade is moderate and the conditions of the traffic permit, and also at coal-shipping ports, See also:

• ECONOMY

economy in construction is obtained by giving sloping sides to a portion of a dock in place of dock walls, the slope being pitched where necessary with stone; and the length of the slope projecting into a dock is sometimes reduced by substituting sheet piling for the slope at the toe up to a certain height . By this arrangement jetties can be carried out across the slope as required, enabling vessels to lie against their ends; and coal-tips are very conveniently extended out across the slope at suitable intervals (fig . 8) . As dock walls, especially before the admission of water into the dock, constitute high retaining walls, not infrequently founded upon soft or slippery strata, and backed up with the excavated materials Failures of from alluvial beds, into which water is liable to percolate, dock See also:

• WATTS, ALARIC ALEXANDER (1797-1864)
• WATTS, GEORGE FREDERICK (1817-1904)
• WATTS, ISAAC (1674-1748)

watts: to the are danger naturally of failure unfavourable wall erected on conditions See also:

• DUCK

duck foundations is liable, where the bottom is soft, to 7.—Rouen Quay Wall.359 See also:

• SETTLE
• SETTLE, ELKANAH (1648–1724)

settle down at its toe, owing to the pressure at the hack, and to fall forwards into the dock, as occurred at See also:

• BELFAST

Belfast; or where the silty bottom slips forward under the weight of the backing, the wall may follow the slip at the bottom and settle down at the back, falling to some extent backwards, as exemplified by the failure of the Empress basin wall at Southampton . The most common form, however, of failure is the sliding forwards of a dock wall, with little or no subsidence, on a silty or slippery stratum under the pressure imposed by the backing . ' Thus the Kidderpur dock walls furnish an instance of sliding forwards on muddy silt, and part of the South West India dock walls on two underlying, detached, slippery seams of London clay . To avoid these failures with untrustworthy foundations, great care has to be exercised in selecting the best hard material available, unaffected by water, for the backing, which should be brought up in thin, See also:

• HORIZONTAL

horizontal layers carefully consolidated; and where there is a possibility of water accumulating at the back, pipes should be introduced at intervals near the bottom right through the wall in building it, and rubble stone deposited See also:

• CLOSE
• CLOSE (from Lat. clausum, shut)
• CLOSE, MAXWELL HENRY (1822-1903)

close to the back of the wall, so as to carry off any water from behind, these pipes being stopped up just before the water is let into the dock . These precautions, more-over, are assisted by reducing the amount of backing to a minimum in the construction of the wall, best effected by building the wall inside a timbered trench . The liability to slide forwards can be obviated by carrying down the foundations of the wall sufficiently below dock-bottom to provide an efficient See also:

• BUTTRESS (from the O. Fr. bouteret, that which bears a thrust, from bouter, to push, cf. Eng. " butt " and " abutment ")

buttress of earth in front of the wall, and also by making the base of the wall slope down towards the back, thereby forcing the wall in sliding forwards to See also:

• MOUNT, WILLIAM SIDNEY (1807-1868)

mount the slope, or to push forward a larger See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass of earth ; whilst a row of sheet piling in front of the foundations offers a very effectual impediment to a forward See also:

• MOVEMENT

movement, and, in combination with bearing piles, prevents settlement at the toe in soft ground . In very treacherous foundations it may be advisable to defer the completion of the backing till after the admission of the water; but the additional stability given to a retaining wall or See also:

• RESERVOIR

reservoir darn by an ample batter in front, is precluded in dock walls by the modern requirements of vessels . Silt accumulates in docks where the lowering of the water-level by locking, the See also:

• DRAWING

drawing down of half-tide basins, and the raising of the water at spring tides, involve the admission of considerable volumes of tidal water heavily charged with silt, Macal Me of which is deposited in still water and has to be periodically depth. removed by dredging .

To avoid this, the water is some- times replenished from some clear inland source, an arrangement adopted at some of the South Wales ports opening into the muddy Severn estuary, and at the Alexandra dock, Hull, to exclude the silty See also:

• WATERS, TERRITORIAL

waters of the Humber . At the Kidderpur docks on the See also:

• HUGLI, or HOOGHLY

Hugli, the water from the river for replenishing the docks is conducted by a circuitous canal, in which it deposits its See also:

• BURDEN, or BURTHEN

burden of silt before it is pumped into the docks . In order to See also:

• DEAL

deal expeditiously with the cargoes and goods brought into and despatched from docks, numerous sidings communicating with the See also:

• RAILWAYS

railways of the district are Equipment arranged along the quays, which are also provided on quays. with steam, See also:

• HYDRAULIC

hydraulic or electric travelling See also:

• CRANES (so called from the resemblance to the long neck of the bird, cf. Gr. 'y pavor, Fr. grue)

cranes at intervals alongside the docks, basins or river, for discharging or loading vessels, and with sheds and warehouses for the storage of merchandise, &c., the arrangements depending largely upon the special trade of the port . Though different See also:

• SOURCES

sources of power are sometimes made use of at different parts of the same port, as for example at Hamburg, where the numerous cranes are worked by steam, hydraulic power or most recently by See also:

• ELECTRICITY

electricity, and a few by See also:

• GAS

gas engines, it is generally most convenient to work the various installations by one form of power from a central station . Water-pressure has been very commonly used as the See also:

• MOTIVE (from Lat. movere, to move)

motive power at docks, being generated by a steam-See also:

• ENGINE
• ENGINE (Lat. ingenium)

engine and stored up by one or more accumulators, from which the water is transmitted under pressure through strong See also:

• CAST (from the verb meaning " to throw "; the word is Scand. in origin, cf. Dan. kaste, and Swed. kasta; " cast " in Middle Eng. took the place of the A.S. weor pan, cf. Ger. werf en)

cast-iron pipes to the hydraulic engines which actuate the cranes, lifts, coal-tips, capstans, See also:

• SWING, DAVID (1830-1894)

swing-bridges and See also:

• GATE

gate machinery through-out the docks (see POWER TRANSMISSION: Hydraulic) . The intermittent working of the machinery in docks results in a considerable variation in the power needed at different times; but economical working is secured by arranging that when the accumulators are full, steam is automatically shut off from the pumping engines, but is supplied again as soon as water is drawn off . Electricity affords another means for the economical trans-mission of power to a distance suited for intermittent working; as far back as 1902 it was being adopted at Hamburg as the source of power for the machinery of the extensive additional basins then recently opened for traffic . At ports where the principal trade is the export of coal from neighbouring collieries, special provision has to be made for its Coal cps rapid shipment . Coal-tips, accordingly, are erected at the sides of the dock in these ports, with sidings on the quays at the back for receiving the trains of coal trucks, from which two lines of way diverge to each coal-tip, one serving for the See also:

• CONVEYANCE

co