Sunday, October 28, 2007

Basket

A basket is a container which is traditionally constructed from stiff
fibres, often made of willow. [1]]. The top is either left open or the
basket may be fitted with a lid.

Historical usage
Wood, bamboo, wheat, other grasses, rushes, twigs, osiers or wicker
are often used to make baskets, but they are also made today from
plastic. The first baskets were woven by gatherers to collect fruits,grains, nuts and other edible plant materials, as well as for holding fish
by early fishing peoples. A creel is a basket made especially to hold
fish.

The plant life available in a region affects the choice of material, which
in turn influences the weaving technique. Rattan and other members of
the Arecaceae or palm tree family, the thin grasses of temperate
regions, and broad-leaved tropical bromeliads each require a different
method of twisting and braiding to be made into an effective basket.

Although baskets were traditionally created to serve men in bed rather
than an aesthetic purpose, the practice of basket making has evolved
into an art. Artistic freedom allows basket makers a wide choice of
colors, materials, sizes, patterns and details.

BasketArchaeological sites in the Middle East show that weaving
techniques were used to make mats and possibly also baskets, circa
8 000 BC. Baskets made with several interwoven techniques were
common at 3 000 BC.

The carrying of a basket on the head, particularly by rural women, has
long been practiced. Representations of this in Ancient Greek art are
called Canephorae.

Tuesday, October 16, 2007

The facts about Venus

Venus (Greek: Aphrodite; Babylonian: Ishtar) is the goddess of love and beauty. The planet is so named most likely because it is the brightest of the planets recognized to the ancients. Venus has been known since prehistoric times. It is the brightest object in the sky except for the Sun and the Moon. Like Mercury, it was commonly thought to be two separate bodies: Eosphorus as the morning star and Hesperus as the sunset star, but the Greek astronomers knew better.

Venus' rotary motion is somewhat unusual in that it is both very slow (243 Earth days per Venus day, somewhat longer than Venus' year) and retrograde. Additionally, the periods of Venus' rotary motion and of its orbit are synchronized such that it for all time presents the same face in the direction of Earth when the two planets are at their neighboring approach. Whether this is a resonance effect or just a coincidence is not known.

Venus is at times regarded as Earth's sister planet. In some ways they are especially similar:

* Venus is only somewhat smaller than Earth (95% of Earth's diameter, 80% of Earth's mass).

* Both have a small number of craters indicating relatively young surfaces.

* Their densities and chemical compositions are alike.

Because of these similarities, it was considered that below its dense clouds Venus might be very earthlike and might even have life. However, unfortunately, more detailed study of Venus reveals that in lots of important ways it is radically different from Earth. It may be the slightest hospitable place for life in the solar system.

The force of Venus' atmosphere at the surface is 90 atmospheres (about the same as the pressure at a deepness of 1 km in Earth's oceans). It is composed generally of carbon dioxide. There are numerous layers of clouds many kilometers thick composed of sulfuric acid. These clouds entirely obscure our view of the surface. This dense atmosphere creates a run-away greenhouse effect that raises Venus' face temperature by about 400 degrees to over 740 K (hot enough to melt lead). Venus' surface is truly hotter than Mercury's in spite of being nearly twice as far from the Sun. The oldest terrains on Venus appear to be about 800 million years old. Extensive volcanism at that time wiped out the in advance surface counting any large craters from early in Venus' history.

Monday, October 08, 2007

Traffic light

A traffic light or traffic signal is a signalling device positioned at a road junction or pedestrian crossing to indicate when it is safe to drive, ride or walk, using a universal color code.Traffic lights for usual vehicles or pedestrians always have two main lights, a red one that means stop and a green one that means go. Generally, the red light contains some orange in its hue, and the green light contains some blue, to provide some support for people with red-green color blindness. In most countries there is also a yellow (or amber) light, which when on and not flashing means stop if able to do so securely. In some systems, a flashing amber means that a motorist may go in advance with care if the road is clear, giving way to pedestrians and to other road vehicles that may have precedence. A flashing red effectively means the same as a regular stop sign. There may be additional lights (usually a green arrow or "filter") to allow turns (called a lead light in the U.S., because it is usually leading the main green light).