Amorphous Solid

There are two main classes of solids: crystalline and amorphous. What distinguishes them from one another is the nature of their atomic-scale structure. The essential differences are displayed in Figure 2. The salient features of the atomic arrangements in amorphous solids (also called glasses), as opposed to crystals, are illustrated in the figure for two-dimensional

Cable

The first successful stranded iron wire rope was developed in 1831–34 by Wilhelm Albert, a mining official of Clausthal

Ciliate

The cilia are usually arranged in rows, known as

Todos Os Santos Bay

Also called  All Saints Bay,  Portuguese  Baía De Todos Os Santos,   sheltered bay of the Atlantic Ocean, eastern coast of Brazil. A natural harbour, it is 25 miles (40 km) long and 20 miles (32 km) wide. Salvador, the principal seaport and capital of Bahia state, is on the peninsula that separates the bay from the Atlantic. Todos os Santos Bay receives the Paraguaçu River and is surrounded by the Recôncavo, a fertile coastal lowland. Its main channel is

Probus, Marcus Aurelius

The son of a Balkan military officer, Probus served with distinction in the army and apparently was eastern praetorian prefect when his troops proclaimed him emperor in opposition to Florian, who was soon killed by his own men. Probus' reign was spent in continual frontier warfare against hostile tribes on the Rhine and Danube, complicated

Chasuble

Liturgical vestment, the outermost garment worn by Roman Catholic priests and bishops at mass and by some Anglicans and Lutherans when they celebrate the Eucharist. The chasuble developed from an outer garment worn by Greeks and Romans called the paenula or casula (“little house”), a conical or bell-shaped cloak made from a semicircular piece of cloth sewn partially

Alunogen

A sulfate mineral formed by sulfate solutions that attack aluminous minerals; alunogen is hydrated aluminum sulfate, formulated Al2(SO4)3×18H2O. It typically occurs as an efflorescence or crevice filling in pyrite-containing coal formations, shales, or slates, as well as in the gossan (weathered capping) of sulfide ore deposits and in volcanic fumarole deposits. In older

La Tène

(French: The Shallows), archaeological site at the eastern end of Lake Neuchâtel, Switz., the name of which has been extended to distinguish the Late Iron Age culture of European Celts. La Tène culture originated in the mid-5th century BC, when the Celts came into contact with Greek and Etruscan influences from south of the Alps. This culture passed through several phases

La Plata River

Spanish  Río De La Plata,   river in east-central Puerto Rico, rising on the western slope of Mount Santa (2,963 feet [903 m]), a peak of the Sierra de Cayey. Part of the stream is impounded by Lake Carite; the reservoir's outlet diverts waters for a series of hydroelectric stations on the Guamaní River in the coastal Guayama area to the south. The La Plata itself flows about 45 miles (70 km) northwest and north, dropping

Islam, Sacred places and days

The most sacred place for Muslims is the Ka'bah sanctuary at Mecca, the object of the annual pilgrimage. It is much more than a mosque; it is believed to be the place where the heavenly bliss and power touches the earth directly. According to Muslim tradition, the Ka'bah was built by Abraham. The Prophet's mosque in Medina is the next in sanctity. Jerusalem follows in third

Diplomatics

The study of documents. The term is derived from the Greek word diploma, meaning “doubled” or “folded.” Besides the documents of legal and administrative import withwhich it is properly concerned, diplomatics also includes the study of other records such as bills, reports, cartularies, registers, and rolls. Diplomatics is therefore a basic and not simply an auxiliary

Cairo, Development of the city

Modern urban growth began in the 1830s, but only during Isma'il's reign (1863–79) was the city fundamentally transformed. Influenced by Baron Haussmann's renovation of Paris, Isma'il ordered the construction of a European-style city to the west of the medieval core. French city-planning methods dominated the design of the districts of Al-Azbakiyah (with its large park), 'Abdin, and Isma'iliyah

Hope

City, seat (1939) of Hempstead county, southwestern Arkansas, U.S., about 35 miles (56 km) northeast of Texarkana. It was founded in 1852 as a station on the Cairo and Fulton (now Union Pacific) Railroad and was named for the daughter of James Loughborough, a railroad land commissioner who laid out the town site. It developed as a shipping centre for timber and agricultural products, notably