Tuesday, December 25, 2007

The facts about Mercury

Mercury is the in close proximity planet to the Sun and the eighth biggest. Mercury is somewhat slighter in diameter than the moons Ganymede and Titan but more than twice as enormous.

Mercury's orbit is exceptionally eccentric; at perihelion it is just 46 million km from the Sun but at aphelion it is 70 million. The position of the perihelion processes regarding the Sun at a very slow rate. 19th century astronomers made extremely careful explanation of Mercury's orbital parameters but could not sufficiently explain those using Newtonian mechanics. The tiny differences between the experimental and predicted values were a slight but nagging problem for many decades. It was thought that one more planet (sometimes called Vulcan) slightly nearer to the Sun than Mercury power account for the discrepancy. But in spite of much effort, no such planet was found. The real reply turned out to be much more dramatic: Einstein's General Theory of Relativity! Its right forecast of the motions of Mercury was a main factor in the early acceptance of the theory.

Monday, December 17, 2007

Vehicle

The Trikke is a Human mechanical Vehicle (HPV) This article is about the means of transport. For additional uses see Vehicle (disambiguation).

Vehicles are lifeless means of transportation. They are nearly everyone often man-made (e.g. bicycles, cars, motorcycles, trains, ships, and aircraft), although some other means of transportation which are not made by man can also be called vehicles; examples include icebergs and floating tree trunks.

Vehicles possibly will be propelled by animals, e.g. a chariot or an ox-cart. However, animals on their own, although used as a means of transportation, are not called vehicles. This includes humans carrying another human, for example a child or a disabled person.

Vehicles that do not voyage on land are often called crafts, such as watercraft, sailcraft, aircraft, hovercraft and spacecraft.

Most land vehicles contain wheels. Please observe the wheel article for examples of vehicles with and without wheels.

Movement without the rally round of a vehicle or an animal is called locomotion. The word vehicle itself comes starting the Latin vehiculum

Wednesday, December 12, 2007

Abstract art

Abstract art is now typically understood to mean art that does not depict objects in the natural world, but instead uses color and form in a non-representational way. In the very near the beginning 20th century, the term was more often used to describe art, such as Cubist and Futurist art, that depicts real forms in a simplified or rather reduced way—keeping only an allusion of the original natural subject. Such paintings were often claimed to capture astonishing of the depicted objects' immutable intrinsic qualities rather than its external appearance. The additional precise terms, "non-figurative art," "non-objective art," and "non-representational art" keep away from any possible ambiguity.

Tuesday, December 04, 2007

Bay of Bengal

The Bay of Bengal is a cove that forms the northeastern ingredient of the Indian Ocean. It resembles a triangle in form, and is enclosed on the east by Malay Peninsula, and on the west by India. On the northern pour of the "bay" lies the Bengal region, comprising the Indian state of West Bengal and the country of Bangladesh, thus the name. The southern boundaries arrive at the island country of Sri Lanka, and the Indian Union Territory of Andaman and Nicobar Islands.

The Bay of Bengal occupies a region of 2,172,000 km². It is bordered by India and Sri Lanka to the West, Bangladesh to the North, and Myanmar and the southern division of Thailand to the East. Its southern border extends as an imaginary line from Dondra Head at the southern end of Sri Lanka to the northern angle of Sumatra. A number of huge rivers – Ganges, Brahmaputra, Irrawaddy, Godavari, Mahanadi, Krishna and Cauvery – run into the Bay of Bengal. Among the vital ports are Yangon, Kolkata/Calcutta, Chittagong, Cuddalore, Kakinada, Machlipatnam, Madras, Paradip and Vishakapatnam.

Monday, November 26, 2007

Fresh skin-care tips

Select fresh, in nature grown fruit and vegetables for the highest benefits. Avoid making more than you have need for a single application. Clean and sanitize all countertops and combination utensils ahead of making any of the recipes. First clean all fruit and vegetables before using as ingredients. Take all ingredients out of the fridge for up to an hour before integration. Don't let fruit acquire any space heater than room temperature.

Fresh fruit and vegetables are particularly high in acids. If you apply anything to your skin and come across a burning sensation, take out immediately and apply cool water. If you are in the care of a dermatologist and on acne medications, please consult with your physician first.

Monday, November 19, 2007

Butter chicken

Butter chicken or murgh makhani is an Indian dish accepted in countries all over the world that have a tradition of Indian restaurants. While the dish's general recipe is well known, the actual flavour can differ from restaurant to restaurant even within Delhi. Butter chicken is usually served with naan, roti, parathas or steamed rice.

It is a dish prepared by marinating a chicken overnight in a yoghurt and spice mixture usually together with garam masala, ginger, lemon or lime, pepper, coriander, cumin, turmeric, chilli, methi and garlic. It is in various ways like to chicken tikka masala. The chicken is then roasted or dry as a bone.

Monday, November 12, 2007

Sound measurement

The decibel (dB) is a logarithmic part of measurement that expresses the magnitude of a physical quantity (usually power) qualified to a specified or implied reference level. Its logarithmic natural history allows very large or very small ratios to be represented by a convenient number, in a related manner to scientific notation. Since it expresses a ratio of two quantities, it is a dimensionless unit. The decibel is useful for a extensive variety of measurements in acoustics, physics, electronics and other disciplines because it linearizes a physical value -- e.g. light intensity or level of noise -- in which exponential changes of magnitude are perceived by humans as being more or less linearly related.

The decibel is not a SI unit. In April 2003, the International Committee for Weights and Measures (CIPM) measured a recommendation for its inclusion in the SI system and decided not to adopt that recommendation. Subsequent the SI convention, the d is lowercase, as it represents the SI prefix deci-, and the B is capitalized, as it is an abbreviation of a name-derived unit, the bel.

Monday, November 05, 2007

SOFAR channel in sound

When sound spreads out evenly in each and every one directions, the intensity drops in proportion to the inverse square of the distance. However, in the ocean there is a layer also called the 'deep sound channel' or SOFAR channel which can imprison sound waves at a particular depth, allowing them to travel much further. In the SOFAR channel, the speed of sound is lesser than that in the layers above and below. Just as light waves will refract towards a section of higher index, sound waves will refract towards a region where their speed is reduced. The result is that sound gets small in the layer, much the way light can be confined in a sheet of glass or optical fiber.

A similar consequence occurs in the atmosphere. Project Mogul successfully used this consequence to detect a nuclear explosion at a considerable distance.

Monday, October 29, 2007

Other methods of Sound


In these methods the time dimension has been replaced by a measurement of the inverse of time (frequency).

Kundt's tube is an example of an testing which can be used to measure the speed of sound in a small volume. It has the advantage of being able to assess the speed of sound in any gas. This method uses a powder to make the nodes and antinodes able to be seen to the human eye. This is an example of a compressed experimental setup.

A tuning fork can be held near the mouth of a long pipe which is plunging into a barrel of water. In this system it is the case that the tube can be brought to resonance if the length of the air column in the pipe is equal to ({1+2n}λ/4) where n is an integer. As the antinodal point for the tube at the open end is slightly outside the mouth of the pipe it is best to find two or more points of quality and then measure half a wavelength between these.

Here it is the case that v = fλ.

Monday, October 22, 2007

Experimental methods

A range of different methods are there for the measurement of sound in air.

Single-shot timing methods

The simplest concept is the dimension made using two microphones and a fast recording device such as a digital storage scope. This method uses the following idea.

If a sound foundation and two microphones are arranged in a straight line, with the sound source at one end, then the following can be measured:

1. The distance between the microphones (x), called as microphone basis. 2. The time of arrival between the signals (delay) reaching the dissimilar microphones (t)

Then v = x / t

An earliest method is to create a sound at one end of a field with an object that can be seen to move when it creates the sound. When the observer sees the sound-creating machine act they start a stopwatch and when the observer hears the sound they stop their stopwatch. Again using v = x / t user can calculate the speed of sound. A division of at least 200 m between the two experimental parties is required for good results with this method.

Monday, October 15, 2007

Basic concept of sound

The transmission of sound can be explain using a toy reproduction consisting of an array of balls organized by springs. For a real material the balls stand for molecules and the springs stand for the bonds between them. Sound passes through the representation by compressing and increasing the springs, transmitting energy to neighboring balls, which transmit energy to their springs, and so on. The speed of sound through the model depends on the inflexibility of the springs (stiffer springs transmit energy more quickly). Effects like spreading and reflection can also be understood using this model.

In a real material, the inflexibility of the springs is known as the elastic modulus, and the mass corresponds to the density. All extra things being equal, sound will travel more slowly in denser materials, and faster in stiffer ones.

Monday, October 08, 2007

Speed of sound
Sound is a trouble of mechanical energy that propagates through matter as a wave (through fluids as a density wave, and through solids as both density and shear waves). Sound is further characterized by the general properties of waves, which are frequency, wavelength, period, amplitude, speed, and direction (sometimes speed and path are combined as a velocity vector, or wavelength and direction are combined as a wave vector).

Humans make out sound by the sense of hearing. By sound, we usually mean the vibrations that travel through air and are audible to people. However, scientists and engineers use a wider meaning of sound that includes low and high frequency vibrations in the air that cannot be heard by humans, and sensations that travel through all forms of matter, gases, liquids, solids, and plasmas.

The substance that supports the sound is called the medium. Sound propagates as waves of alternating pressure, causing limited regions of compression and rarefaction. Particles in the average are displaced by the wave and oscillate. The scientific study of the combination and reflection of sound waves is called acoustics.

Monday, September 24, 2007

Pollutants in water

Pollutants in water consist of a large spectrum of chemicals, pathogens, and physical chemistry or sensory changes. A lot of the chemical substances are toxic. Pathogens can apparently produce waterborne diseases in either human or animal hosts. Alteration of water’s physical chemistry includes acidity, conductivity, temperature, and eutrophication. Eutrophication is the fertilization of surface water by nutrients that were previously scarce. Even many of the municipal water supplies in developed countries can present health risks.

Monday, September 17, 2007

The Vanilla orchid

The main type harvested for vanillin is Vanilla planifolia. Even though it is native to Mexico, it is now extensively grown throughout the tropics. Madagascar is the world's largest producer, Additional sources include Vanilla pompona and Vanilla tahitiensis (grown in Tahiti), though the vanillin satisfied of these species is much less than Vanilla planifolia.

Vanilla grows as a vine, mountaineering up an existing tree, pole, or other support. It can be full-fledged in a wood (on trees), in a plantation (on trees or poles), or in a "shader", in increasing orders of productivity. Left alone, it will produce as high as possible on the support, with few flowers. Every year, growers fold the senior parts of the plant downwards so that the plant stays at heights accessible by a standing human. This also very much stimulate flowering.

Monday, September 10, 2007

Earth's atmosphere

Earth's atmosphere is a layer of gases surrounding the planet Earth and retain by the Earth's gravity. It contains roughly (by molar content/volume) 78% nitrogen, 20.95% oxygen, 0.93% argon, 0.038% carbon dioxide; trace amounts of other gases, and a changeable amount (average around 1%) of water vapor. This mixture of gases is usually known as air. The atmosphere protects life on Earth by captivating ultraviolet solar radiation and reducing temperature extremes between day and night.

There is no exact border between the atmosphere and outer space, it slowly becomes thinner and fades into liberty. Three quarters of the atmosphere's mass is within 11 km of the terrestrial surface. In the United States, people who travel above a height of 80.5 km (50 statute miles) are selected astronauts. An altitude of 120 km (400,000 ft) marks the boundary where atmospheric property becomes obvious during re-entry. The Kármán line, at 100 km (328,000 ft), is also often regarded as the boundary between atmosphere and outer space.

Tuesday, September 04, 2007

Yachting

Yachting is a physical action connecting boats. It may be racing sailing boats, cruising to far-away shores, or day-sailing along a coast.
Whilst sailing's invention is prehistoric, racing sailing boats is supposed to have started in the Netherlands some time in the 17th century, whence it soon made its way to England where custom-built racing "yachts" began to emerge. In 1851, a challenge to an American yacht racing club in New York led to the beginning of the America's Cup, a regatta won by the New York Yacht Club awaiting 1983, when they finally lost to Australia II. For now, yacht racing continued to develop, with the development of recognised classes of racing yachts, from small dinghies up to huge maxi yachts.
These days, yacht racing and ship racing are common participant sports around the developed world, mainly where favourable wind conditions and access to reasonably sized bodies of water are available. Most yachting is conducted in salt water, but smaller craft can be - and are - raced on lakes and even huge rivers.
Whilst there are many different types of racing vessels, they can normally be separated into the larger yachts, which are larger and contain facilities for extensive voyages, and smaller harbour racing craft such as dinghies and skiffs.

Monday, August 27, 2007

Vegetable

Vegetable is a cookery term which usually refers to an edible part of a plant. The definition is traditional rather than scientific and is somewhat random and subjective. All parts of herbaceous plants eaten as food by humans, whole or in part, are in general considered vegetables. Mushrooms, though belong to the biological kingdom fungi, and are also commonly considered vegetables. In common, vegetables are consideration of as being savory, and not sweet, although there are many exceptions. Nuts, grains, herbs, spices and culinary fruits are usually not exact vegetables.

Tuesday, August 21, 2007

Education

It is extensively accepted that the process of education is lifelong. Studies have exposed that the child is educated by the experiences it is exposed to in the womb even before it is born.
Individuals receive relaxed education from a variety of sources. Family members, peers, books and mass media have a strong on the informal education of the individual.
Education also say about the discipline, a body of theoretical and applied research that draws on other disciplines such as psychology, philosophy, computer science, linguistics, neuroscience, sociology and anthropology.

Monday, August 13, 2007

Blazer

A blazer or boating jacket is a kind of jacket, generally double-breasted even though single-breasted blazers have become more general in recent times. A blazer looks like a suit jacket except for that it generally has patch pockets with no flaps, and metal shank buttons. A blazer's cloth is usually of a resilient nature as it is used in schools and was used for sport. They frequently form part of the uniform dress of bodies, such as airlines, schools, yacht or rowing clubs, and private security organizations. As sporting dress has become more modified to the activity, the blazer has become limited to clubs' social meetings. Generally, blazers are navy blue, but nearly every color and mixture of colors has been used, particularly by schools and sporting organizations.

Tuesday, August 07, 2007

Public transport

Public transport, public transportation, public travel or mass transit comprises all transport systems in which the passengers do not tour in their own vehicles. While it is generally taken to include rail and bus services, wider definitions would comprise scheduled airline services, ship, taxicab services etc. – any system that transports members of the universal public. A further restriction that is sometimes practical is that it must take place in shared vehicles that would bar taxis that are not shared-ride taxis.

Monday, July 30, 2007

Jewellery and society

Jewellery is factually any piece of fine material used to decorate oneself. Although in earlier times jewellery was created for more convenient uses, such as wealth storage and pinning clothes together, in recent times it has been used almost completely for beautification. The first pieces of jewellery were made from likely materials, such as bone and animal teeth, shell, wood and engraved stone. Jewellery was often made for people of high importance to show their status and, in many cases, they were covered with it.Jewellery is made out of almost every material recognized and has been made to garnish nearly every body part, from hairpins to toe rings and many more types of jewellery. While high-quality and artistic pieces are made with gemstones and valuable metals, less pricey costume jewellery is made from less-valuable materials and is mass-produced. Form and function Kenyan man exhausting tribal beads.

Over time, jewellery has been used for a number of reasons: Currency, wealth display and storage, purposeful Symbolism Protection and Artistic display Most cultures have at some point had a practice of observance large amounts of wealth stored in the form of jewellery. Numerous cultures move wedding dowries in the form of jewelry, or create jewelry as a means to store or display coins. On the other hand, jewellery has been used as a currency or trade good; a mostly poignant example being the use of slave beads.

Tuesday, July 24, 2007

Parrot

Parrots or psittacoses pronounced is an order namely Psittaciformes of birds that includes about 350 species. They are frequently grouped into two families: the Cacatuidae (cockatoo), and the Psittacidae (parrots), but one may find many variations. Some sources split parrots into three families. Citation needed the term "true parrot" is not used by the majority of bird keepers, biologists and lay people and is a source of confusion.
All members of the order have a usually erect stance and a characteristic curved beak shape with the upper mandible having slight mobility in the joint with the skull. All parrots are zygodactyl, with two toes at the front of each foot and two at the flipside, and all parrot eggs are white in color.

Monday, July 16, 2007

Camera

A camera is a device used to take pictures, either alone or in series, with or without sound, such as with video cameras. The name is resulting from camera obscura, Latin for dark chamber, an early mechanism for projecting images in which an whole room functioned much as the internal workings of a modern photographic camera, except there was no way at this time to record the image little of physically tracing it. Cameras may work with the chart spectrum or other portions of the electromagnetic spectrum.
Every camera consists of a number of enclosed chambers, with an opening or aperture at one end for light to go into, a recording or viewing surface for capturing the light at the other conclusion. This diameter of the aperture is often forbidden by a diaphragm mechanism, but some cameras have a fixed-size opening.
Video and digital cameras use electronics, frequently a charge coupled device or sometimes a CMOS sensor to detain images which can be transfer or stored in tape or computer memory within the camera for later playback or processing. Traditional cameras capture glow onto photographic film or photographic plate.

Wednesday, July 11, 2007

Hardware and software design

Supercomputers using custom CPUs traditionally gained their speed over conventional computers through the use of innovative designs that allow them to carry out many tasks in parallel, as well as complex feature engineering. They tend to be expert for certain types of computation, usually numerical calculations, and perform poorly at more general computing tasks. Their memory hierarchy is very cautiously designed to ensure the processor is kept fed with data and commands at all times—in fact, much of the performance difference between slower computers and supercomputers is due to the memory hierarchy. Their I/O systems tend to be planned to support high bandwidth, with latency less of an issue, because supercomputers are not used for transaction processing.

As with all highly parallel systems, Amdahl's law applies, and supercomputer designs devote great effort to eliminate software serialization, and using hardware to speed up the remaining bottlenecks.

Tuesday, June 26, 2007

Rigid-inflatable boat

A rigid-inflatable boat (RIB) or rigid-hulled inflatable boat, (RHIB) is a light-weight high performance and high capacity boat built with a solid, shaped hull and flexible tubes at the gunwale. The design is steady and seaworthy. The inflatable collar means that resilience is not lost if a great quantity of water is shipped aboard. The RIB is an expansion of the inflatable boat.
We can use RIBs as rescue craft, safety boats for sailing, dive boats or tenders for larger boats and ships because of their trivial draught, high maneuverability, speed and relative immunity to damage in low speed collisions are advantages in these applications.

RIBs are generally designed as hydroplaning hulls, it has 7 meters length. The speed of the RIB depends on its weight, power, load, and sea conditions. A standard RIB of about 10 metres of length with two parallel rows of seating down the centre of the craft is propelled by two Johnson 200 Horsepower engines, with the aim of getting the craft to roughly 75 knots before jumping 10 ft off the tops of waves.

Tuesday, June 12, 2007

Punt

A punt is a flat-bottomed boat with a square-cut bow, planned for use in small rivers or other shallow water. Punting refers to boating in a punt; the punter normally propels the punt by pushing beside the river bed with a pole.
Punts were initially built as cargo boats or platforms for fowling and angling but in modern times their use is almost wholly confined to pleasure trips on the rivers in the university towns of Oxford and Cambridge in England and races at a few summer regattas on the Thames.
A customary river punt differs from many other types of wooden boat in that it has no keel, stem or sternpost. In its place it is built rather like a ladder with the main structure being two side panels connected by a series of 4 in (10 cm) cross planks, known as "treads", spaced about 1 foot (30 cm) apart.
The first punts are traditionally linked with the River Thames in England and were built as small cargo boats or platforms for fishermen. Pleasure punts — particularly built for recreation — became popular on the Thames between 1840 and 1860. Some other boats have a similar shape to a traditional punt — for example the Optimist training dinghy or the air boats used in the Everglades — but they are normally built with a box construction instead of the open ladder-like design of a traditional Thames pleasure punt.

Wednesday, June 06, 2007

Wherry

The Norfolk wherry is a black-sailed trader, kind of boat on The Broads in Norfolk. It is double-ended with the pole steeped well forward, tinted black with a single gaff sail. Mostly clinker-built, it would carry about 25 tons of goods.
Wherries were able to arrive at better boats just off coast and take their cargoes off to be transported inland through the broads and the rivers.
Before wherries, there was the Norfolk Keel, a quadrangle rigged, transom sterned clinker-built boat, 54 feet by 14 feet, and able to carry 30 tons of goods. The keel had been built since the middle Ages and the plan probably went back to the Viking invasion. After 1800, the Norfolk Keel (or 'keel wherry') disappeared, partly since a wherry could be sailed with fewer crew, and it had limited maneuverability and lacked speed.
A special wherry wheelbarrow was used to unpack cargo, e.g. stone, from the wherries. It was made from wood and strengthens with iron bands. It had no legs; therefore it could be rested on the 11 inches wide plank on the surface of the wherry.

Monday, May 28, 2007

Kayak

A kayak is a little human-powered boat. It classically has a covered deck, and a cockpit covered by a spray deck. It is propelled by a double-bladed paddle by sitting paddlers. The kayak was used by the inhabitant Ainu, Aleut and Eskimo hunters in sub-arctic regions of northeastern Asia, North America and Greenland. Modern kayaks come in a wide diversity of designs and materials for particular purposes. Kayaks are frequently referred to as canoes in Great Britain and Ireland.
Traditional kayaks typically accommodate one, two or infrequently three paddlers who sit facing ahead in one or more cockpits below the deck of the boat. If used the spray deck or comparable waterproof garment attach securely to the edges of the cockpit, prevent the entry of water from waves or spray, and making it possible in some styles of boat, to roll the kayak upright again without it filling with water or eject the paddler.
Kayaks differ definitely in design and history from canoes, which are more flat-bottomed boats propel by single-bladed paddles by a kneeling paddler, even though some modern canoes may be difficult for a non-expert to distinguish from a kayak. One benefit to a kayak is that with a canoe's high bow, it is harder to paddle against the wind. As Kayaks do not have such high sides, it is easier to paddle on a breezy day.

Sunday, May 20, 2007

Hovercraft

A hovercraft, or air-cushion vehicle (ACV), is a vehicle or craft that can be hold up by a cushion of air dispossessed downwards against a surface close below it, and can in principle travel over any relatively smooth surface, such as gently sloping land, water, or marshland, while having no substantial contact with it.
Hovercraft has one or more parts of engines (some craft, such as the SR-N6, have one engine with a drive split through a gearbox). One engine drives the fan (the impeller) which is in charge for exciting the vehicle by forcing air under the craft. The air therefore must exit throughout the "skirt", lifting the craft above the area which the craft resides. One or more additional engines are used to offer thrust in order to propel the craft in the favorite direction. Some hovercraft utilized ducting to allow one engine to perform both tasks by directing some of the air to the skirt, the rest of the air passing out of the back to push the craft forward.

Sunday, May 13, 2007

Folding boat

A Folding boat is frequently a smaller boat, typically ranging between 8 to 12 feet. This style of boat must also allow for easy lifting which require a glow weight. Folding boats are made from light weight resources such as marine plywood, aluminum or more exotic man-made materials lighter and tougher than aluminum. Folding boats fill a need for people who do not have storage gap for a full-size boat or cannot transport a full-size boat.
There are more than a few folding boat makers and folding kayak makers in the world from the USA, England and Australia with several variations and models. The handyman can also produce their own unit at home with plans or buy designing their own version.
Although there is much to be thought by the advantages of a folding boat, they are not common place in boating and aluminum and inflatable alternatives are far more common despite some folding boats having been sold for several decades.

Monday, April 02, 2007

Bicycle

A hybrid vehicle (HV) is a vehicle that uses two different power sources such as:
* An on-board rechargeable energy storage system (RESS) and a fueled power source for means of transportation force
* Human powered bicycle with sequence assist
* A sail boat with electric control
The term the commonly refers to petroleum electric hybrid vehicle, also called Hybrid-electric vehicle (HEV) which use internal burning engines and electric batteries to power electric motors.
The term hybrid when used in relative with cars also has other uses. Prior to its modern meaning of hybrid force, the word hybrid was used in the United States to mean a vehicle of mixed countrywide origin; generally, a European car fitted with American mechanical components. This significance has fallen out of use. In the import scene, hybrid was often used to describe an engine swap. Some have also referred to flexible-fuel vehicles as hybrids because they can use a combination of different fuels — naturally gasoline and ethanol alcohol fuel.

Tuesday, March 20, 2007

Carts

Carts have been mention in journalism as far back as the second millennium B.C. The Indian sacred book Rig-Veda states that men and women are as corresponding as two wheels of a cart. Hand-carts pushed by humans have been used approximately the world. In the 19th century, for example, some Mormons traveling across the plains of the United States between 1856 and 1860 used handcarts.
Carts were often used for judicial punishments, both to transport the destined – a public humiliation in itself (in Ancient Rome defeated leaders were often carried in the victorious general's triumph) – and even, in England until its replacement by the whipping post under Queen Elizabeth I, to tie the condemned to the cart-tail and administer him or her a public whipping.

Sunday, January 21, 2007

Lighthouse of Alexandria

The Pharos of Alexandria was a lighthouse built in the 3rd century BC on the island of Pharos in Alexandria, Egypt to serve as that port's landmark, and later, a lighthouse. With a height variously estimated at between 115 and 135 metres it was among the tallest man-made structures on Earth for many centuries, and was identified as one of the Seven Wonders of the World by classical writers. It ceased operating and was largely destroyed as a result of two earthquakes in the 14th century AD; some of its remains were found on the floor of Alexandria's Eastern Harbour by divers in 1994. More of the remains have subsequently been revealed by satellite imaging.

Constructed from large blocks of light-colored stone, the tower was made up of three stages: a lower square section with a central core, a middle octagonal section, and, at the top, a circular section. At its apex was positioned a mirror which reflected sunlight during the day; a fire was lit at night. Extant Roman coins struck by the Alexandrian mint show that a statue of a triton was positioned on each of the building's 4 corners. A statue of Poseidon stood atop the tower during the Roman period.

Monday, January 08, 2007

Conjoined twins

Conjoined twins are monozygotic twins, whose bodies are joined together at birth. This occurs where the single zygote of identical twins fails to separate completely, and the zygote starts to split after day 13 following fertilization. This condition occurs in about 1 in 50,000 human pregnancies. Most conjoined twins are now evaluated for surgery to attempt to separate them into separate functional bodies. The degree of difficulty rises if a vital organ or structure is shared between twins, such as brain, heart or liver.

A chimera is an ordinary person or animal except that some of his or her parts actually came from his or her twin. A chimera may arise either from identical twin fetuses, or from dizygotic fetuses, which can be identified by chromosomal comparisons from various parts of the body. The number of cells derived from each fetus can vary from one part of the body to another, and often leads to characteristic mosaicism skin colouration in human chimeras. A chimera may be a hermaphrodite, composed of cells from a male twin and a female twin.

Monday, January 01, 2007

Wildlife

The term wildlife refers to living organisms that are not in any way artificial or domesticated and which survive in natural habitats. Wildlife can refer to flora but more usually refers to fauna. Wildlife is a very general term for life in ecosystems. Deserts, rainforests, plains, and other areas including the most built-up urban sites all have distinct forms of wildlife.

Humans have historically tended to split civilization from wildlife in a number of ways; besides the obvious difference in vocabulary, there are differing expectations in the legal, social, and moral sense. This has been a reason for debate during recorded history. Religions have often declared certain animals to be sacred, and in modern times concern for the environment has aggravated activists to protest the exploitation of wildlife for human benefit or entertainment. Literature has also made use of the traditional human separation from wildlife.