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PIER (older forms per or Pere, from M...

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Originally appearing in Volume V21, Page 590 of the 1911 Encyclopedia Britannica.
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PIER (older forms per or Pere, from Med. See also:Lat. pera; the word for piers out of See also:water. For See also:river piers, where a See also:firm, watertight is of obscure origin, and the connexion with Fr. See also:Pierre, Lat. stratum is found at a moderate See also:depth below the river-See also:bed, the pctr  a, See also:stone, is doubtful; equivalents are Fr. piedroit, pilier, site is often enclosed within a See also:coffer-See also:dam or a See also:plate See also:iron See also:caisson lrunneaue; Ital. pila; Ger . Pfeiler), the See also:term given in See also:architecture carried down into the stratum and raised out of See also:water; and then, to a See also:vertical support in See also:masonry or See also:brickwork, usually rect- after the water has been pumped out and the See also:surface layers angular on See also:plan, which carries an See also:arch or superstructure . The removed, the See also:pier is readily built within the enclosure in the term is also sometimes given to the See also:great circular columns which open See also:air . When, however, a See also:river-See also:bed consists of silt, See also:sand or in some See also:English cathedrals and churches carry the See also:nave See also:arches. other soft materials extending down to a considerable See also:depth, In See also:early See also:Christian churches, when See also:antique columns, such as brickwork See also:wells are gradually sunk tc a See also:firm stratum by removing abounded in See also:Rome, were not procurable, square piers took the the material within them with grabs, and on them the piers are See also:place of columns and sometimes alternated with them . The built out of water; or bottomless caissons are carried down by introduction of vaulting, however, in the 11th See also:century, neces- excavating their interiors under compressed air, and the piers sitated a support of much greater dimensions than those which are built on See also:top of them within a plate-iron enclosure, a See also:system adopted for the piers of the See also:Brooklyn, St See also:Louis, Forth and other large See also:bridges, and essential for forming See also:foundations on sloping See also:rock, such as was encountered in places under the See also:Firth of Forth . The methods indicated above as employed for the foundations of the piers of bridges under favourable conditions belong equally to the foundations of other structures (see FOUNDATIONS); but there are some methods which, by combining See also:bridge piers and their foundations in a single structure, appertain entirely to piers . Thus iron See also:screw piles, sunk by turning into the soft bed of a river till they reach a firm stratum or one sufficiently consolidated by the superincumbent layers to enable it to support the wide See also:blades of the screws with the See also:weight imposed on them, were formerly often arranged in converging clusters joined together at the top, so as to serve as the piers of bridges having several comparatively small spans, and intended for carrying lightly constructed See also:railways across See also:rivers in See also:India and elsewhere . Hollow, See also:cast-iron, cylindrical piles also, with a broad circular disk at the bottom to increase their bearing surface, have been used for piers founded in sandy or silty strata bolted together with a specially strong bottom See also:ring, sometimes made of wrought iron and having a cutting edge, have been often employed for the construction of the river piers of bridges, being gradually carried down to a watertight stratum by excavating inside, and subsequently filled up solid with See also:concrete and See also:brick-See also:work; the piers of the Charing See also:Cross and See also:Cannon See also:Street bridges across the See also:Thames are notable instances of the See also:adoption of this method, which is well illustrated by the piers of the bridges across the River Chittravati in India (fig . 2) . Sometimes, instead of two or more See also:independent cylinders being sunk, the whole site of a pier is enclosed within a wrought-iron caisson, usually divided into sections ccago by vertical partitions, which is sunk and filled up solid in the same way as cylinders, a system adopted, for instance, for the piers of the bridge across the Hawkesbury River in New See also:South See also:Wales . See also:Promenade Piers.—The term pier is often applied to See also:works sheltering harbours, such as the See also:Tynemouth piers, which are strictly breakwaters . Landing stages also, whether solid or open, have for a See also:long See also:time been called piers, as the See also:Admiralty Pier and the See also:Prince of Wales's Pier at See also:Dover; but the open promenade piers which See also:form a See also:common feature at seaside resorts are the type of pier best known to the See also:general public .

These piers are supported upon open pilework of See also:

timber or iron, and consequently expose little surface to waves in storms and do not interfere with the See also:drift of See also:shingle or sand along the See also:coast (fig . 3).1 Timber piles are best suited for withstanding the shocks of vessels at landing stages, at which places they are generally used; but since they are subject to the attacks of the See also:teredo, and expose a considerable surface to the waves, iron piles are generally adopted for the See also:main portion of these piers . The See also:pioneer of these piers was the old See also:chain pier at See also:Brighton, which was erected in 1822-1823 . It was founded upon See also:oak piles, was 1136 ft. long, and had a timber landing-See also:stage at the end . It consisted of four spans suspended from chains on the See also:model of the Menai Suspension Bridge, then in course of construction, and was destroyed by a See also:gale in See also:December 1896 . A wider and more See also:modern type of pier was erected at the See also:west end of Brighton in 1865–1866, of considerable thickness; they are sunk to the requisite depth by lowering a See also:pipe down the inside of the See also:pile to the bottom and emitting a powerful See also:jet of water which, stirring up the soft material and scouring it away from under the disk, causes the pile to descend . This system was first adopted for the piers of a railway viaduct See also:crossing the wide, sandy See also:Kent and See also:Leven estuaries opening into See also:Morecambe See also:Bay (fig . I) . Cast-iron cylinders, consisting of a See also:series of rings formed of segments all and subsequently extended; whilst a new pier was completed in 1900 near the site of the old chain pier, I700 ft. tong . The See also:Southport pier, erected in 1859–186o and afterwards prolonged, furnishes an example of an iron pier supported on disk piles sunk in sand as described above (fig . I); whilst the much more commonly used iron screw piles, adopted as early as 1847 for an open landing-pier on the Irish coast at Courtown, which was exposed to a great littoral drift of sand, are shown as the mode of support for the pier 1 The Engineer (1888), i . 38o, 381 and 384 .

at St Leonards (fig . 3) . The length given to these promenade piers depends mainly on the slope of the See also:

foreshore, which deter-mines the distance from the See also:shore at which a sufficient depth is reached for steamers of moderate See also:draught to come alongside the end of the pier . Thus, whereas a length of 90o ft. has sufficed for the St Leonards pier on a somewhat steep, shingly See also:beach, the pier at See also:Ryde, constituting the See also:principal landing-place for the Isle of See also:Wight passengers, has had to be carried out about See also:half a mile across a See also:flat alluvial foreshore to reach water deep enough for the See also:access of the steamboats crossing the See also:Solent . The vast sands, moreover, at the outlet of the Ribble See also:estuary, stretching two or three See also:miles in front of Southport at See also:low water of See also:spring tides, have necessitated the construction of a pier 4395 ft. long merely to get out to an old See also:flood-See also:tide channel, which is now completely severed by the sands at low water from all connexion with the river . (L . F .

End of Article: PIER (older forms per or Pere, from Med. Lat. pera; the word for piers out of water. For river piers, where a firm, watertight is of obscure origin, and the connexion with Fr. Pierre, Lat. stratum is found at a moderate depth below the river-bed, the pctr
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FRANKLIN PIERCE (1804—1869)

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