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last SG · 2005-03-28T01:23:34+00:00

Celtic Sea The Celtic Sea (Irish: An Mhuir Cheilteach) is the area of the Atlantic Ocean off the south coast of Ireland. It is bounded to the east by Saint...

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Tierra del Fuego

Tierra del Fuego (Spanish: Land of Fire) is an archipelago at the southernmost tip of South America. In 1881 it was divided between Argentina and Chile. The archipelago consists of a main island (Isla Grande de Tierra del Fuego, often called Tierra del Fuego as well), and a group of smaller islands. It is separated from the continent by the Strait of Magellan. The southern point of the archipelago, in Chile, forms Cape Horn.

A true-colour image of Tierra del Fuego captured by NASA's Terra satellite on March 28, 2003.

The main industries are oil, natural gas, sheep farming and ecotourism. The largest island is Tierra del Fuego, or Isla Grande, with an area of 48,100 km². Half of this island, and the islands west and south of it, are part of the Magallanes Region of Chile, the capital and chief town of which is Punta Arenas, situated on the mainland across the strait. The biggest Chilean towns are Porvenir, on the main island, and Puerto Williams, on Navarino Island. Puerto Toro lies a few kilometers south of Puerto Williams and is the southernmost town in the world.

Cities of Tierra del Fuego

The eastern part of the archipelago belongs to Argentina, being part of the Tierra del Fuego Province; its capital, Ushuaia, is the world's most southerly city, the other important town being Rio Grande, near the Atlantic coast.

Its name comes from Ferdinand Magellan, who was the first European to pass it in 1520, he (likely incorrectly) believed he was seeing the many fires (fuego in Spanish) of the Amerindians, which were visible from the sea. He believed that the "Indians" were waiting in the forests to ambush his armada. It is however, more likely that the fires he witnessed were from natural sources such as lightning.

Cerro Sombrero Village, Chile. It was founded to serve as a petroleum campsite.

Four native Fuegians, including "Jemmy Button" (Orundellico), were brought from Tierra del Fuego by Robert Fitzroy on the first voyage of the Beagle in 1830. They were taken to meet the King and Queen in London and were to an extent celebrities. The surviving three returned to Tierra del Fuego with the Beagle with Charles Darwin, who made extensive notes about his visit to the islands.

Issue #210

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Cape Reinga

Cape Reinga (or Te Rerenga Wairua in the Maori language) is the northwesternmost tip of the Aupouri Peninsula, at the northern end of the North Island of New Zealand.

Cape Reinga

Cape Reinga is located over 100 km north of the nearest small town of Kaitaia. There is a road all the way but suitable vehicles can travel much of the way via Ninety Mile Beach and Te Paki stream bed.

Meeting of the seas

The cape separates the Tasman Sea from the Pacific Ocean. From the lighthouse it is possible to watch the tidal race, as the Tasman Sea meets the Pacific Ocean. This makes for unsettled waters just off the coast.

Cape Reinga Lighthouse

Cape Reinga is often mistaken as being the northernmost point of the North Island. North Cape's Surville Cliffs, 30 kilometres to the east of Cape Reinga, are slightly more northerly.

Maori mythology

According to Maori mythology, the spirits of the dead travel to Cape Reinga on their journey to the afterlife in the spiritual homeland of Hawaiki. At Cape Reinga they depart the mainland by leaping off the ancient pohutukawa tree on the cape. They turn briefly at the Three Kings Islands for one last look back towards the land, then continue on their journey. Reinga means the leaping-off place and Te Rerenga Wairua means the leaping-off place of spirits.

Lighthouse

The lighthouse at Cape Reinga was built in 1941 and first lit during May of that year.

The Cape Reinga lighthouse replaced a lighthouse located on nearby Motuopao Island, which had been built 1879. Accessing the lighthouse was difficult due to the rough seas in the area. In 1938, it was decided to move the lighthouse to Cape Reinga for safety reasons. The complete lantern fittings from Motuopao Island were reused at Cape Reinga.

Cape Reinga Lighthouse

The lighthouse was fitted with a 1,000 watt electrical lamp that could be seen for 26 nautical miles (48 km). The lamp was powered by a diesel generator.

In 1987, the lighthouse was fully automated and the lighthouse keepers were withdrawn. The lighthouse is now monitored remotely from Wellington. In May of 2000 the original lens and lamp were replaced by a 50 watt beacon. The beacon is powered by batteries that are recharged by solar cells. The beacon flashes every 12 seconds and can be seen for 19 nautical miles (35 km).

Issue #211

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Johnson Street Bridge

The Johnson Street Bridge is a bascule bridge that spans the harbor of Victoria, British Columbia. It is nicknamed "Big Blue" because of its distinctive blue color.

The Johnson Street Bridge

It was designed by the Strauss Bascule Company and built by the City of Victoria Engineering Department. The bridge was completed in January 1924 at a cost of Can$918,000. The original wood deck was replaced by a steel grid in 1966 and the steel structure was repainted in 1979 as part of an extensive renovation.

The Johnson Street Bridge opening

The bridge has two separate structures, the railroad and the highway, that operate independently. The main span is 148 ft (45 m) in length and weighs 350 tons. The approaches are fixed girders, the east is 110 ft (34 m) and the west is 73 ft (22 m). The counterweights are made of hollow concrete and total 780 tons. Daily traffic is 30,000 vehicles.

Issue #212

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Lake Huron

Lake Huron is one of the five Great Lakes of eastern North America and separates Michigan from Ontario. Georgian Bay, the easternmost part of Lake Huron, is entirely within Canada. Lake Huron's name comes from early French explorers who named it based on the Huron Indians inhabiting the region.

The Great Lakes from space; Lake Huron is the third from the left.

Lake Huron is separated from Lake Michigan, which lies at the same level, and connects by the narrow Straits of Mackinac, making them geologically and hydrologically the same body of water (sometimes called Lake Michigan-Huron). Lake Superior is slightly higher than both. It drains into the St. Marys River at Sault Ste. Marie which then flows southward into Lake Huron. The water then flows south to the St. Clair River, at Port Huron, Michigan and Sarnia, Ontario. Cities on Lake Huron include: Saginaw, Michigan, Bay City, Michigan, Alpena, Michigan, Cheboygan, Michigan, St. Ignace, Michigan, Port Huron, Michigan, and Sarnia, Ontario.

The Great Lakes Waterway continues thence to Lake St. Clair, the Detroit River and Detroit, Michigan, into Lake Erie and thence, via Lake Ontario and the St. Lawrence River, to the Atlantic Ocean.

Ipperwash Beach, Lake Huron.

The surface of Lake Huron is 579 feet (176 metres) above sea level. The lake's average depth is 195 feet (59 metres), while the maximum depth is 750 feet (230 metres). It covers an area of about 23,000 square miles (59 600 square kilometres). It contains 3,538 cubic km of water. The shoreline extends roughly 3,827 miles (6,159 kilometres). Like the other Great Lakes, it is the remnant of the larger Glacial Lake Agassiz, formed by melting ice as the continental glaciers retreated.

A notable feature of the lake is Manitoulin Island, the world's largest lake island.

Issue #213

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Rio Grande

Known as the Rio Grande in the United States and as the Río Bravo (or, more formally, the Río Bravo del Norte) in Mexico, the river rises in the San Juan Mountains of Colorado, USA, flows through the San Luis Valley, then south into New Mexico through Albuquerque and Las Cruces to El Paso, Texas, on the U.S.Mexico border.

The Rio Grande flowing in Big Bend National Park

The river has, since 1845, marked the boundary between Mexico and the United States from the twin cities of El Paso, Texas, and Ciudad Juárez, Chihuahua, to the Gulf of Mexico. As such, it was across this river that Texan slaves fled when seeking their freedom, aided by Mexico's liberal colonization policies and abolitionist stance.

The major international border crossings along the river are Ciudad Juárez and El Paso; Laredo, Texas, and Nuevo Laredo, Tamaulipas; McAllen-Hidalgo, Texas, and Reynosa, Tamaulipas; and Brownsville, Texas, and Matamoros, Tamaulipas. Other notable border towns are the Texas/Coahuila pairings of Del RioCiudad Acuña and Eagle PassPiedras Negras.

Use of the water of the Rio Grande is regulated by the Rio Grande Compact, an interstate pact between Colorado, New Mexico and Texas; and a treaty between the United States and Mexico. The Rio Grande is over-appropriated, that is, there are more users for the water than there is water in the river. Since the summer of 2003, much of the river from southern New Mexico to the Big Bend National Park has been dry. Ecologists fear that unless rainfall returns to normal levels during the next few years and strict water conservation measures are adopted by communities along the river, the Rio Grande may soon become extinct.

The watershed of the Rio Grande

The Rio Grande rises in high mountains and flows for much of its length at high elevation; El Paso is 1,147 m (3,762 feet) above sea level. In New Mexico the river flows through the Rio Grande Rift from one sediment-filled basin to another, cutting canyons between the basins and supporting a fragile bosque ecosystem in its floodplain. From El Paso eastward the river flows through desert. Only in the sub-tropical lower Rio Grande Valley is there extensive irrigated agriculture. The river ends in a small sandy delta at the Gulf of Mexico. During periods of extended dry weather, the river will actually cease flowing into the Gulf.

Millions of years ago, the Rio Grande ended at the bottom of the Rio Grande Rift in Lake Cabeza de Vaca. But about 1 million years ago the stream was "captured" and began to flow east.

Issue #214

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Gaspé Peninsula

The Gaspé Peninsula or just the Gaspé (la Gaspésie in French) is a North American peninsula on the south shore of the Saint Lawrence River, in Quebec. It extends into the Gulf of Saint Lawrence and is bounded on the south by New Brunswick, from which it is partially divided by Chaleur Bay and the Restigouche River.

NASA satellite image of the Gaspé Peninsula. Part of Anticosti Island appears to the northeast

The interior is rugged, being a northward extension of the Appalachian Mountains. A section of the International Appalachian Trail travels along the peninsula.

Highway 132 circles the peninsula, with one branch following the coast and the other cutting across the peninsula at Sainte-Flavie. Forillon National Park is found at the tip of the Gaspé.

Together with the Magdalen Islands, the Gaspé makes up the Quebec region of Gaspésie-Îles-de-la-Madeleine.

There is a town on the peninsula that is also called Gaspé. The easternmost point of the peninsula jutting into the Gulf of St. Lawrence is called Cap Gaspé.

The name "Gaspé" comes from a Mi'kmaq word gespeg meaning "land's end".

Inside the coast

Travelling along the northern shore of the Gaspé Peninsula, a small highway numbered the 198 turns off towards the higher lands of the Gaspé Peninsula. A few minutes into your voyage up from sea level, the majestic beauty of the forest of the Gaspé Peninsula will captivate your attention. As you head further and further into the hills, you'll cross several small rivers and reach the town of Murdochville at about 660 meters up from sea level. The small town has been around for 50 years or so and offers a large history of ups and downs. Currently, the small town is leading the way in the development of several large windmill farms that are amazing to see. The towers sprout up over the city limits with one of the largest wind generating capacities in the world. As you continue along your voyage, the 198 winds its way along the York River to spill out on the city of Gaspé.

Southern coast

At the communities of Restigouche and Gesgapegiag there are sizeable Mi'kmaq settlements. There is a small remnant left of a once-thriving English-speaking community. It is found opposite New Brunswick and on the coast of Chaleur Bay, especially in the settlements of Carleton and New Carlisle; despite these origins, the majority of people speak French. As a tribute to the colonial Loyalist communities that once inhabited the now more diverse area, a section of New-Richmond has recreated a Loyalist settlement (called le village loyaliste).

Issue #215

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Taklamakan

The Taklamakan (also Taklimakan) is a desert of Central Asia, in the Xinjiang Uighur Autonomous Region of the People's Republic of China. Some references state that Taklamakan means "if you go in, you won't come out"; others state that it means "Desert of Death" or "Place of no return".

Dust storm in Taklamakan from space, June 25, 2005

"Makan" is a Turkic word meaning "place", of Arabic origin: the word may mean something different if treated as original pre-Islamic native Turkic.

It covers an area of 270,000 km² of the Tarim Basin, extending between roughly 78° to 88° E longitude and 37° to 40° N latitude. It is crossed at its northern and at its southern edge by two branches of the Silk Road. The key oasis towns are Kashgar, Yarkand, and Khotan (Hetian) in the South-West, Kuqa and Turfan in the North, and Loulan and Dunhuang in the East.

The White Jade River flows into the Taklamakan.

The archeological treasures found in its sand buried ruins point to Tocharian, early Hellenistic, and Indian/Buddhistic influences. Its treasures and dangers have been vividly described by Aurel Stein, Sven Hedin, Albert von Le Coq, and Paul Pelliot.

Numerous mummies, some 4,000 years old, have been found in the region. They show the wide range of peoples who have passed through. Many of the mummies appear European and may have been members of the Tocharian people, who spoke an Indo-European language.

Later, the Taklamakan was inhabited by Turkic peoples. Starting with the Tang Dynasty, the Chinese periodically extended their control to the oasis cities of the Taklamakan in order to control the important silk route trade across Central Asia. Periods of Chinese rule were interspersed with rule by Turkic and Mongol and Tibetan peoples. The present population consists largely of Turkic Uyghur and Kazakh people in the countryside, while the population of the larger cities is predominantly Han Chinese.

Bruce Sterling has written a science fiction short story titled Taklamakan and set in this desert.

Issue #216

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Bay of Plenty

The Bay of Plenty, often abbreviated to BoP, is a region of New Zealand situated around the body of water of the same name.

The bay itself

The bay stretches from the Coromandel Peninsula in the west to Cape Runaway in the east. The region is bound by the Kaimai and Mamaku Ranges in the west and extends inland to the sparsely populated forest lands around Rotorua, Kawerau and Murupara. Several islands are located in the bay, notably Mayor Island/Tuhua, Motiti Island, Whale Island and, most famously, the active volcano of Whakaari/White Island.

Location of Bay of Plenty

The bay was named by James Cook some time during October or November 1769. Cook named it the Bay of Plenty after he noticed the abundant food supplies at several Maori villages he visited on the coast, in stark contrast to the observations he had made earlier in Poverty Bay.

The region

The local government region has a 2004 estimated population of 257,500, which is forecasted to increase to 277,900 by the year 2011. The region is dominated by two cities: Tauranga (population 106,500) and Rotorua (55,100). As a compromise between the cities, the town of Whakatane was selected as the seat for the Bay of Plenty Regional Council. Other towns in the region include Te Puke, Katikati and Opotiki. Agriculture and tourism are the region's two main industries, with the geothermal region around Rotorua being a popular tourist destination.

Issue #217

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Malaspina Glacier

The Malaspina Glacier in southeastern Alaska is the largest piedmont glacier in non-polar North America. It is about 65 km (40 mi) wide and 45 km (28 mi) long, with an area of some 3,900 sq km (1,500 sq mi).

The Malaspina Glacier is so large that it can only seen in its entirety from space; this 1994 photo from STS-66, on a rare clear day, is of an area about 100 km (60 mi) across.

It forms where several valley glaciers, primarily the Seward Glacier and Agassiz Glacier, spill out from the Saint Elias Mountains onto the coastal plain facing the Gulf of Alaska between Icy Bay and Yakutat Bay. Although it fills the plain, nowhere does it actually reach the water and so does not qualify as a tidewater glacier.

The Malaspina is up to 600 meters thick in places, with a bottom estimated at up to 300 meters below sea level. There are two lakes on the margin of the glacier; Oily Lake at the foot of the Samovar Hills between the Agassiz and Seward glaciers, and Malaspina Lake at the southeast margin, close to Yakutat Bay.

Study of radar data and aerial photographs dating back to 1972 shows that the Malaspina-Seward system lost about 20 m (60 ft) of its thickness between 1980 and 2000; because the glacier is so large, that was sufficient to contribute 1/2 of one percent of the rise in the global sea level.

The glacier is protected within the boundaries of the Wrangell-St. Elias National Park and Preserve.

Issue #218

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Danube-Black Sea Canal

The Danube-Black Sea Canal is a canal in Romania which runs from Cernavodã on the Danube to Agigea (southern arm) and Nãvodari (northern arm) on the Black Sea.

Danube in blue, the Danube-Black Sea Canal in red

Statistics

It opened in 1984, and the 64km canal reduces the distance by boat from Constanta to Cernavoda; by 400 km, being an important part of the European canal system that links the North Sea to the Black Sea. The Canal has a width of 60 metres and a depth of 7 metres. The Northern arm has a length of 26.6 km, width of 50 m and a depth of 5.5 metres.

A barge on the Danube-Black Sea Canal

Construction

The canal took over nine years to construct, 300 million m³ of soil was excavated, by hand, by over 30,000 people. 4.2 million m³ of reinforced concrete was used in the construction.

There earliest plans for building of this canal were created in 1839, but after the building of a railway connection in 1860, goods could be easily transported from Constanta by railroad, so the plans were forgotten. In 1927, the Romanian engineer Jean Stonescu made a new set of plans.

The construction began only in 1949. During the communist purges, more than 40,000 people, most of them convicts for political reasons in Romanian forced-labour camps, were worked to death on the project between 1949 and 1953. As such, it became known as the Death Canal (Canalul Mortii in Romanian). In 1953, the project came again to a halt, all work being cessed for another 23 years. In 1976, the project was reopened and the southern arm was finished in 1984, with the northern arm being finished in 1987.

Map of the forced labour camps at the Canal

The cost of the building of the canal is estimated to be around $2 billion, and was supposed to be recovered in 50 years. However, nowadays it has a yearly profit of only a little over 3 million.

Issue #219

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Tonga Trench

The Tonga Trench is located in the Pacific ocean and is 32,000 ft (9,900 m) deep.

Tonga Trench is marked by solid line with barbs on overriding plate. Dashed line represents the trend of the Vitiaz Trench lineament, and dotted-dashed line show trend of the Fiji Fracture Zone. Trend of Louisville Ridge marked by dotted line.

The trench and its forearc form an active convergent margin between two plates of the lithosphere, the Pacific Plate being subducted into the earth's semi-molten aesthenosphere, and the northeastern corner of the Australian Plate overriding it. The Tonga trench extends north-northeast from the North Island of New Zealand.

The convergence is taking place at breath-taking speed: a rate estimated at approximately 15 cm/yr (by Lonsdale, 1986); however, recent Global Positioning Satellite measurements indicate in places a convergence of 24 cm/yr across the northern Tonga Trench, which is the fastest plate velocity yet recorded on the planet (Bevis et al., 1995).

Such oceanic trenches are important sites for the formation of what will become continental crust and for recycling of material back into the mantle. Along the Tonga Trench mantle-derived melts are transferred to the island arc systems, and abyssal oceanic sediments and fragments of oceanic crust are collected.

Issue #220

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Camel's Hump

Camel's Hump is Vermont's third highest mountain, but perhaps its most recognized. Part of the Green Mountain range, it is one of the oldest mountains on earth. With its neighbor to the north, Mount Mansfield, it borders the notch that the antecedent Winooski River has carved through this area over eons.

Camel's Hump, Vermont, USA

Camel's Hump is more notable for its shape than its height of 4,083 feet. Isolated from neighboring peaks by the Winooski Valley and glacial action, the mountain's conical silhouette is distinctive, if misleading. While it looks somewhat volcanic from the east and west, the movement of glacial ice created its current form. It has two "humps", with the southernmost being the higher, and a steep drop to the south as a result of a quarrying action of the ice passing over it.

Since Europeans first saw the mountain, probably on Samuel de Champlain's 1609 trip down Lake Champlain to the west, it has had a number of names related to its shape. "Camel's Hump" is a modified version of "Camel's Rump." The "Couching Lion" was an earlier name, a version of the French heraldic lion couchant image.

A view northwest from Camel's Hump mountain in Vermont, looking toward Lake Champlain.

The Abnaki name for the mountain was "ta wak be dee esso wadso," or "tahwahbodeay wadso" (wadso meaning mountain), which has been variously translated as "resting place", "sit-down place", and "prudently, we make a campfire in a circle near water (and rest) at this mountain."

One of only two spots of true Arctic tundra in Vermont exists on the summit (the other being on Mount Mansfield).

Camel's Hump is featured on the state seal and the state quarter.

Issue #221

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Celtic Sea

The Celtic Sea is that area of the Atlantic Ocean which is bounded by the south coast of Ireland, the southwest coast of Wales and the north coast of Devon and Cornwall in England west of the Bristol Channel. It does not really have south and west boundaries, although it is generally considered to stop at the same longitude as the west edge of Ireland and at the same latitude as the western tip of Brittany.

Map of the Celtic Sea, an arm of the Atlantic.

The name is commonly used by workers in the oil and fishing industries to avoid nationalist connotations. The Celtic Sea is separated from the Irish Sea by St George's Channel.

Coccoliths in the Celtic Sea.

Issue #222

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Isthmus of Panama

The Isthmus of Panama is the narrow strip of land that lies between the Caribbean Sea and the Pacific Ocean, linking North and South America. It was formed some 3 million years ago during the Pliocene epoch. It lies in the nation of Panama, and is cut by the Panama Canal. Like many isthmuses, it is a location of great strategic value due to its importance in both land and sea transportation.

Isthmus of Panama

Issue #223

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Cox's Bazar

Cox's Bazar in Bangladesh is the world's longest natural beach (120 km). It is located 152 km south of Chittagong. Coxs Bazar is also known by the name Panowa, the literal translation of which means yellow flower. Its other old name was Palongkee. The modern Cox's Bazar derives its name from Lieutenant Cox (died 1798), an army officer serving in British India. It is also one of the fishing ports of Bangladesh.

Cox's Bazar

History

The history of the place goes back to the Mughal period. On his way to Arakan, when the Mughal Prince Shah Shuja passed through the hilly terrain of the present day Coxs Bazar, he was attracted to the scenic and captivating beauty of the place. He commanded his forces to camp there and his retinue moving into 1,000 palanquins halted there for some time. A place named Dulahazara, meaning "1,000 palanquins", still exists in the area.

Sunset in Cox's Bazar

After the Mughals, the place came under the control of the Tipras and the Arakanese, followed by the Portuguese and then the British. After Independence it remained as part of East Pakistan. In 1971, the wharf was used as a naval port by Pakistan Navy's gunboats. This and the nearby airstrip of Pakistan Air Force was the scene of intense shelling by the Indian Navy during the Bangladesh Liberation War.

Places

Coxs Bazar, mostly famous for its beautiful sea beach and the sunset, has several other attractions including:

- Aggmeda Khyang, a large Buddhist monastery, and a place revered by around 400,000 Buddhist people of Coxs Bazar; and the Chittagong Hill Tracts.

- Himchari, located about 32 km south of Coxs Bazar, is a picnic spot and famous for its waterfalls.

- Inani, also 32 km south of Coxs Bazar offers sea bathing.

- Maheskhali is a small island (268 suare kilometers) off the Coxs Bazar coast. The island offers panoramic scenic beauty and is covered by low hills and mangrove forests. Adinath, a temple of Shiva, and a Buddhist pagoda are also located on the island.

- Ramu, about 16 km from Coxs Bazar, is the name of a village with sizeable Buddhist population. The village is famous for its handicrafts and homemade cigars.

- Sonadia Island, a small island of only 9 square kilometers
Teknaf, a place situated by the side of Naaf river is the southernmost part of Bangladesh. The place is home to several birds and wild animals.

Cox's Bazar

Issue #224

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Cinnabar

Cinnabar (German Zinnober), sometimes written cinnabarite, is a name applied to red mercury(II) sulfide (HgS), or native vermilion, the common ore of mercury. The name comes from the Greek, used by Theophrastus, and was probably applied to several distinct substances. Other sources say the word comes from the Persian zinjifrah, originally meaning "lost".

Cinnabar

Cinnabar was mined by the Roman Empire for its mercury content and it has been the main ore of mercury throughout the centuries. Some mines used by the Romans are still being mined today. It is generally found as a vein-filling mineral associated with recent volcanic activity and alkaline hot springs.

Cinnabar is generally found in a massive, granular or earthy form, and is bright scarlet to brick red in color. However, it occasionally occurs in crystals with a metallic adamantine luster. The crystals belong to the rhombohedral (trigonal) system, and are generally of rhombohedral habit, sometimes twinned. The twinning in cinnabar is distinctive and forms a penetration twin that is ridged with six ridges surrounding the point of a pryamid. It could be thought of as two scalahedral crystals grown together with one crystal going the opposite way of the other crystal.

Cinnabar presents remarkable resemblance to quartz in its symmetry and optical characteristics. Like quartz, it exhibits circular polarization, and Alfred Des Cloizeaux showed that it possessed fifteen times the optical rotatory power of quartz. It has higher refractive power than any other known mineral, its mean index for sodium light being 3.02, while the index for diamonda substance of remarkable refractionis only 2.42. The hardness of cinnabar is 2 - 2.5, and its specific gravity 8.998.

Cinnabar crystals on Dolomite from China.

Cinnabar is found in all localities which yield mercury, notably Almaden (Spain), New Almaden (California), Idrija (Slovenia), Landsberg, near Ober-Moschel in the Palatinate, Ripa, at the foot of the Apuan Alps (Tuscany), the mountain Avala (Serbia), Huancavelica (Peru), Terlingua (Texas), and the province of Guizhou in China, where very fine crystals have been obtained. Cinnabar is still being deposited at the present day from the hot waters of Sulphur Bank, in California, and Steamboat Springs, Nevada.

Hepatic cinnabar is an impure variety from Idrija in Carniola, in which the cinnabar is mixed with bituminous and earthy matter.

Metacinnabarite is a cubic form of mercury(II) sulfide, this compound being dimorphous.

Cinnabar may be associated with elemental (liquid) mercury and thus be dangerous to handle. Body temperature is often enough to vaporize the mercury out of the rock and this gas can be absorbed through the skin.

Issue #225

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Kariba Dam

The Kariba Dam is a hydroelectric dam in the Kariba Gorge of the Zambezi river basin in Southern Africa. The double curvature concrete arch dam was constructed between 1955 and 1959 at a cost of $135,000,000 for the first stage with only the Kariba South power cavern. Final construction and the additon of the Kariba North Power cavern was not completed until 1977 due to largely political problems for a total cost of $480,000,000. Around 100 workers were killed during construction.

Kariba Dam

It is one of the largest dams in the world at 128 m high and 579 m long. The Kariba supplies 1,320 MW of electricity to parts of both Zambia (the Copperbelt) and Zimbabwe and generates 6,400 GW·h (23 PJ) per annum. Lake Kariba, the reservoir created by the dam, extends for 280 km with a storage capacity of 180 km³.

Lake Kariba

The creation of the reservoir forced resettlement of about 57,000 people living along the Zambezi. In 1960 to 1961, 'Operation Noah' captured and removed around 6,000 large animals and numerous small ones threatened by the lake's rising waters.

Reservoir-induced quakes

Since its construction and filling in the early 1960s, the area has experienced numerous earthquakes, 20 of them in excess of magnitude 5 on the Richter scale, believed to have been induced by the dam reservoir. Seismologists are uncertain as to the exact cause of these quakes as reservoir-induced quakes are still not well understood.

Issue #226

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Long Island Sound

Long Island Sound is an estuary of the Atlantic Ocean and various rivers in the United States. It lies between the coast of Connecticut to the north and Long Island to the south. It is also known as "The Gold Coast" due to its breathtaking properties along the shoreline. Many mansions along with wealthy neighborhoods characterize a good portion of the sound from the cityline of New York out to Setauket and Port Jefferson. The towns of Orient, Greenport, East Marion, Southold, and Mattituck have smaller populations are are located on the extreme eastern tip of the Long Island Sound. They offer great property value as well. And,On the extreme western end, it is bounded on the north side by Westchester County, New York and the Bronx, and connects to the East River. On its eastern end it is connected to Block Island Sound. The sound is considered by some to be the natural border between New England and the Mid-Atlantic states.

New York City waterways: 1. Hudson River, 2. East River, 3. Long Island Sound, 4. Newark Bay, 5. Upper New York Bay, 6. Lower New York Bay, 7. Jamaica Bay, 8. Atlantic Ocean

The Sound is 110 miles (177 km) long and 21 miles (34 km) wide at its widest point. It has an average depth of 78 feet (24 m), with the deepest point being 300 feet (90 m). The volume of water in the Sound is 8 trillion US gallons (30 km³). Including all islands, the Long Island Sound has a shoreline of 548 miles (882 km).

Long Island Sound is shown highlighted in pink between Connecticut (to the north) and Long Island (to the south).

The first European to record the existence of Long Island Sound was the Dutch navigator Adriaen Block, who entered the sound from the East River in 1614.

Several major cities are situated along the Long Island Sound, resulting in a total of more than 8 million people living within its watershed. Major Connecticut cities on the Sound include Bridgeport, New London, Stamford, Norwalk, and New Haven. New York cities on the Sound include New York City (the Bronx borough).

Ferries provide service between Long Island and Connecticut, notably between Port Jefferson, New York and Bridgeport, Connecticut, and Orient Point, New York and New London, Connecticut. Some of the ferries that cross the Long Island Sound carry automobiles as well as passengers.

Underwater cables transmit electricity under the Long Island Sound, most notably the controversial Cross-Sound Cable that runs from New Haven in western Connecticut, to Brookhaven in central Long Island. Scientists debate whether or not these cables are safe for the fragile Long Island Sound environment, especially the underwater lifeforms.

Long Island Sound near Guilford, Connecticut

The Long Island Sound side differs from the Atlantic Ocean side of Long Island because the shorelines here are rocky. The Atlantic Ocean side remains sandy with no rocks. This is due to the formation of Long Island nearly 10,000 years ago as glaciers formed the fish-shaped island.

Many attempts have been made to build a bridge over the sound, including a bridge from Rye, New York to Oyster Bay, New York, from New Haven, Connecticut to Shoreham, New York on Long Island and from Orient Point, New York to Rhode Island.

Long Island Sound has historically had a rich fishery, but in recent years the western part of the sound has become increasingly deficient of marine life. The fishing and lobstering industries have encouraged efforts to identify the cause of the dead water and rectify the problem.

Major environmental problems currently affecting the Sound include hypoxia, toxic substance and pathogen contamination, debris and other man-made pollution, and overdevelopment.

Issue #227

poon cho tang SG

Moroccan Wall

The Moroccan Wall, dubbed The Wall of Shame by the Sahrawi natives of Western Sahara, is a 2,500 km-long system of defensive walls/berms: sand and stone walls about three meters in height with bunkers, fences and landmines, running mainly through Moroccan-occupied Western Sahara. A minor section is located in southeastern Morocco.

Map of the Moroccan Wall

The barrier is longer than the Israeli West Bank barrier and the Berlin Wall. It was gradually built beginning in 1983 with two main functions: to keep the guerrilla fighters of the Polisario Front, which has sought Western Saharan independence since before Spain ended its colonial occupation in 1975, outside and the economically valuable two-thirds of the Western Sahara inside. Effectively, the Polisario controls all areas to the east of the barrier, but these areas are mostly uninhabited.

A large number of Sahrawi refugees are in the Tindouf province of Algeria, where the Polisario is based. Because the barrier is doubled in many places, with a significant distance between the two halves, many Sahrawis are forced to live in this no-man's-land with profound constraints on mobility and accessibility.

International reaction

Western attention to the Moroccan Wall, and to the Moroccan annexation of the Western Sahara in general, has been minimal, apart from in Spain. Once a year, a small demonstration is held against the barrier by a few human rights activists, many of them Italian.

In Africa, the occupation has attracted somewhat more attention: Algeria, which supports the Polisario, and the Organization of African Unity/African Union and United Nations have proposed negotiated solutions.

Issue #228

poon cho tang SG

Tibesti Mountains

The Tibesti Mountains are a group of extinct volcanoes forming a mountain range in the central Sahara desert in the Bourkou-Ennedi-Tibesti prefecture of northern Chad. The northern slopes extend a short distance into southern Libya.

The Tibesti, including Emi Koussi summit, seen from the International Space Station

The mountains are the largest and highest range in the Sahara. The highest peak is Emi Koussi, 3,415 m. Other summits include Kegueur Terbi (3,376 m), Tarso Taro (3,325 m), the active volcano Pic Tousside (3,265 m) and Soborom (3,100 m). While the high peaks themselves are all constituted of volcanic material, the mountains stand on broad uplifted area possibly caused by a mantle plume.

The range has a substantially wetter climate than the arid surrounding desert; annual rainfall is estimated at five inches in some of the highest areas of the mountains.

The area has long been home to the Toubou people, there been trading relations between them and Carthage as far back as the 500's BC. The main town in the area is Zouar, while Bardaï and Aouzou are smaller settlements.

The mountains are known for their cave paintings, mostly dating from the 5th to the 3rd millennium BC, and for the geysers and hot springs around Soboroum.

Issue #229

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