Rhodes, Cecil (John) (b. July 5, 1853, Bishop’s Stortford, Hertford¬ shire, Eng.—d. March 26, 1902, Muizenberg, Cape Colony) Financier, statesman, and empire builder of British South Africa. Rhodes grew up in the English countryside and in 1871 was sent to assist his brother in business in South Africa, where he became interested in diamond mining. He founded De Beers Consolidated Mines (1888), and by 1891 his com¬ pany was mining 90% of the world’s diamonds. Seeking expansion to the north and dreaming of building a Cape-to-Cairo railway, he persuaded Britain to establish a protectorate over Bechuanaland (1884), clashing with Boer president Paul Kruger. He obtained digging concessions from Lobengula (1889), but in 1893 Rhodes overran him militarily. At his insti¬ gation Britain chartered the British South Africa Co. (1889) and put Rhodes in charge. He extended the company’s control to two northern provinces, which were eventually named after him as Southern Rhodesia (now Zimbabwe) and Northern Rhodesia (now Zambia). Interested in the mineral-rich Transvaal, he plotted to overthrow Kruger (1895); the attempt was botched by Leander Starr Jameson, and Rhodes was forced to resign as prime minister of Cape Colony and head of the British South Africa Co. His last years were marked by disappointment and scandal brought about by the scheming of Princess Radziwill. His will bequeathed most of his fortune to establishing the Rhodes scholarship.
Rhodes, Colossus of Enormous that towered more than 100 ft (30 m) over the harbour at the city of Rhodes in Greece. The work of Chares of Lindos, the statue commemorated the raising of Demetrios Poliorcetes’ long siege of Rhodes (305-304 bc). One of the Seven Wonders of the World, it was toppled by an earth¬ quake c. 225 bc. The fallen Colossus was left in place until ad 653, when raiding Arabs broke up its remains and sold the bronze for scrap.
Rhodes scholarship Grant to attend the University of Oxford. The program was established in 1902 by the will of Cecil Rhodes. Until 1976, candidates had to be unmarried male residents in a Commonwealth coun¬ try, the U.S., or South Africa. In 1976 women were accepted. Two candi¬ dates each year are also chosen from Germany. The scholarships, which are highly competitive, are usually fi
statue of the sun god Helios
Colossus of Rhodes, constructed c. 292-280 bc, wood engraving recon¬ struction by Sidney Barclay, c. 1875.
HISTORICAL PICTURES SERVICE, CHICAGO
two years.
Rhodesia Region, south-central Africa, now divided into Zimbabwe in the south and Zambia in the north. Named after British colonial adminis¬ trator Cecil Rhodes, it was administered by the British South Africa Com¬ pany in the 19th century and exploited mostly for its gold, copper, and coal deposits. In 1911 it was divided into Northern and Southern Rhode¬ sia; Southern Rhodesia became a self-governing British colony (1923) and Northern Rhodesia a British protectorate (1924). They joined with Nyasa- land to become the Federation of Rhodesia and Nyasaland (1953-63). See also Malawi.
Rhodesia See Zimbabwe
Rhodesian ridgeback or African lion dog South African hound breed characterized by a narrow band of hair growing forward along its back, against the direction of the rest of the coat. The ridge is inher¬ ited from a half-wild local hunting dog that was crossbred with Euro¬ pean dogs. Strong, active, and of great endurance, it is trim and short- haired, with hanging ears and a glossy brown coat. It stands 24-27 in. (61-69 cm) and weighs 65-75 lbs (30-34 kg). It is an able guard and hunter (especially of lions) and a good companion.
Rhodian Sea Law \'ro-de-on\
Regulations governing trade and navigation in the Byzantine Empire.
Based on a statute in the Code of Jus¬ tinian and on ancient maritime law in Rhodes, the Rhodian Sea Law focused on liability for lost or dam¬ aged cargo. It divided the cost of the losses among the shipowner, the owners of the cargo, and the passengers, thus serving as a form of insurance against storms and piracy. It was effective from the 7th through the 12th century.
rhodium Metallic chemical element, one of the transition elements, chemical symbol Rh, atomic number 45. Chemically related to platinum, it is a precious, silver-white metal mainly used as an alloying agent for the latter element. Rhodium added to platinum in small amounts yields alloys that are harder and that lose mass at high temperatures more slowly than pure platinum. Such alloys are used for laboratory furnace crucibles, spark-plug electrodes, catalysts in very hot chemical environments (including automobile catalytic converters), and high-temperature thermo¬ couples. Because rhodium resists tarnishing at ordinary temperatures and is highly reflective, it is in demand as a surface electroplating for jewelry and other decorative articles. The plated metal is also used for reflecting surfaces in optical instruments.
rhodochrosite \ l ro-d3- , kro-,sIt\ Carbonate mineral composed of man¬ ganese carbonate (MnC0 3 ), a source of manganese for the ferromanga¬ nese alloys used in steel production. It is commonly found in ore veins formed at moderate temperatures, in high-temperature metamorphic deposits, and in sedimentary deposits.
rhododendron \,ro-d3-'den-dr3n\ Any of about 800 diverse species of woody plants that make up the genus Rhododendron in the heath family, notable for their attractive flowers and handsome foliage. They are native chiefly in the northern temperate zone, especially in South Asia and Malaysia. Some are evergreens, others deciduous. Some are low-growing ground covers; others are tall trees. Flowers are usually tubular to funnel- shaped and occur in a wide range of colours: white, yellow, pink, scarlet, purple, and blue. See also azalea.
rhodonite Vro-ds-.nlA Silicate mineral that occurs in various manganese ores, often with rhodochrosite. A manganese silicate, MnSi0 3 , with small amounts of iron and calcium, it is found in the Ural Mountains,
Sweden, Australia, California, New Jersey, and elsewhere. Rhodonite is the primary source of some impor¬ tant manganese oxide deposits, such as the manganese ores of India. Fine¬ grained rhodonite of clean, pink colour is a desirable gem and orna¬ mental stone.
Rhodope Vra-da-peX Moun¬ tains Mountain range, Balkan Pen¬ insula, southeastern Europe. Extending southeast from Bulgaria through Macedonia and Greece, the range is drained by tributaries of the Maritsa River. It forms an important climatic barrier, protecting the Aegean low-
Rhodonite from Pajsberg, Swed.
COURTESY OF THE FIELD MUSEUM OF NATURAL HISTORY, CHICAGO; PHOTOGRAPH, JOHN H. GERARD
Rhodesian ridgeback.
WALTER CHANDOHA
© 2006 Encyclopaedia Britannica, Inc.
rhodopsin ► Ribera I 1617
lands from cold northerly winds. The mountains were a refuge for Slavic peoples during the period of Turkish rule (15th—19th century), and ancient customs survive. The lakes, river valleys, and extensive forests form the basis of a tourist industry.
rhodopsin \r6-'dap-son\ or visual purple Light-sensitive, purple-red organic pigment contained in the rod cells of the retina that allows the eye to see in black and white in dim light. It is composed of opsin, a protein, linked to retinal, a conjugated molecule (see conjugation) formed from vitamin A. Photons of light that enter the eye are absorbed by retinal and cause it to change its configuration, starting a biochemical chain of events that ends with impulses being sent along the optic nerve to the brain. In bright light, to protect rod cells from overstimulation, rhodopsin breaks down into retinal and opsin, both of which are colourless. In dim light or darkness the process is reversed (dark adaptation), and purple-red rhodop¬ sin is reformed. Similar light-sensitive compounds made of retinal and other opsin proteins are the pigments in the retina’s cone cells responsible for colour vision in bright light.