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shield,in geology: see continentcontinent,
largest unit of landmasses on the earth. The continents include Eurasia (conventionally regarded as two continents, Europe and Asia), Africa, North America, South America, Australia, and Antarctica.
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shield,piece of defensive armorarmor,
apparatus for defense of persons, horses, and such objects as vehicles, naval vessels, and aircraft. Body armor developed early as protective suits made of such materials as leather, shells, wood, and basketwork, later supplemented by metal.
..... Click the link for more information. , worn on the arm or shoulder to ward off weapons during combat, used prior to the dominance of gunpowder. Originally for individual defense during hand-to-hand combat, it is the most primitive and universal item of defensive armor. Shields were made of hide or wood, often reinforced with metal, and could be round, oblong, or rectangular. As armies developed, soldiers carried matching shields to link together for fighting in formations, such as those used by Assyria (2500 B.C.). A soldier's body armor complemented his shield. Heavy infantry carried larger shields than did skirmishers, cavalry carried smaller shields, and bowmen often carried none. Modern riot police carry plastic shields for protection.
(1) A type of protective armament used to ward off the blows of cold-steel weapons. Shields were worn on the arm, which was passed through straps or rigid bands. The earliest shields were of various shapes and were made of wood, leather, or plaited twigs. Mesopotamians of the third millennium B.C. used wooden shields that were partially covered with copper plates. Bronze shields appeared in the second millennium B.C. in Assyria. The bronze shields of the kings of Urartu were covered with relief work and cuneiform characters.
The round, wooden—less often, iron—shields used in ancient Greece bore warriors’ emblems, such as the dolphin or the lion. The Romans used round, iron shields and four-cornered shields made of wood and leather. Shields in early medieval Europe were also round and had umbones. Almond-shaped shields came into wide use in the 11th century; in the mid-13th century they were supplanted by triangular shields.
Symbols—rudimentary coats of arms—appeared on shields in the 12th century. In the second half of the 14th century and in the 15th century, the warriors of northern Rus’ used the paveza, a rectangular pavis with rounded corners. The field of the pavis was divided into three parts by a trough, which facilitated defensive movements. The Russian cavalry used round shields from the 14th to early 16th centuries. Shields became smaller with improvements in armor and went out of use when firearms were developed.
The shield served as a symbol of military honor and victory. Pagan warriors took oaths on their shields. In 907, in Tsar’grad (Constantinople), Oleg “hung his shield on the gates as a sign of victory.” Shields in Rus’ were made by special artisans known as shchitniki (shield-makers). There was in Novgorod a street called Shchitnaia (Shield), where, apparently, the shield-makers lived.
(2) An armor plate with slots for gun or machine-gun sights. The shield is used to protect the gun crew and the gun’s mechanisms from bullets and shrapnel. On some towed weapons, the shield is mounted forward of the sight and sighting devices.
REFERENCEKirpichnikov, A. N. Drevnerusskoe oruzhie, issue 3. Leningrad, 1971.
D. A. AVDUSIN
(geology), the largest positive structure of cratons, contrasted to the platform. Within the shields there are outcrops of strongly metamorphosed Precambrian crystalline rocks (granites, gneisses, and schists), which constitute the basement of the cratons. Shields are irregular, flat uplifts and are usually uplifted segments of the crust. Their outlines show great stability for long periods of time.
The term “shield” was first suggested by E. Suess in 1885 for the extensive outcrops of Precambrian rocks in North America (the Canadian Shield) and Northern Europe (the Baltic Shield). The term “crystalline shield” was proposed by N. S. Shatskii in 1947.