Probably the oldest tower still standing is the Leaning Tower of Pisa in Pisa, Italy built from 1173 until 1372.The oldest towers in the United States are the Milwaukee City Hall, built in 1895 in Milwaukee, Wisconsin and the Woolworth Building, completed in 1913 in New York City.
The structure of the mammalian eye can be divided into three main layers or tunics whose names reflect their basic functions: the fibrous tunic, the vascular tunic, and the nervous tunic.
Black & White Photography strikes a balance between inspiration and information, traditional and digital for the monochrome photographer.
The candle was developed independently in many countries. The Egyptians and Cretans made the candle from beeswax, as early as 3000 BC. The early candle was made from various forms of natural fat, tallow, and wax. In the 18th century, spermaceti, an oil produced by the sperm whale, was used to produce a superior candle. Late in the 18th century, colza oil and rapeseed oil came into use as much cheaper substitutes. Paraffin was first distilled in 1830, and revolutionized candle-making, as it was an inexpensive material which produced a high-quality, odorless candle that burned reasonably cleanly. The industry was devastated soon after, however, by the distillation of kerosene (confusingly also called paraffin oil or just paraffin). This excellent fuel for lamps gave the candle its current status as a primarily decorative item. Recently resin based candles that are freestanding and transparent have been developed, with the claim that they burn longer than traditional paraffin candles.
The ability of the human eye to distinguish colors is based upon the varying sensitivity of different cells in the retina to light of different wavelengths. The retina contains three types of color receptor cells, or cones. One type, relatively distinct from the other two, is most responsive to light that we perceive as violet, with wavelengths around 420 nm. (Cones of this type are sometimes called short-wavelength cones, S cones, or, misleadingly, blue cones.) The other two types are closely related genetically and chemically. One of them (sometimes called long-wavelength cones, L cones, or, misleadingly, red cones) is most sensitive to light we perceive as yellowish-green, with wavelengths around 564 nm; the other type (sometimes called middle-wavelength cones, M cones, or misleadingly, green cones) is most sensitive to light perceived as green, with wavelengths around 534 nm.
A Muslim (Arabic: مسلم) is an adherent of the religion of Islam. The feminine form of 'Muslim' is Muslimah (Arabic: مسلمة). Literally, the word means "one who submits to God)".
An automobile (from Greek auto, self and Latin mobile moving, a vehicle that moves itself rather than being moved by another vehicle or animal) or motor car (usually shortened to just car) is a wheeled passenger vehicle that carries its own motor. Most definitions of the term specify that automobiles are designed to run primarily on roads, to have seating for one to eight people, to typically have four wheels, and to be constructed principally for the transport of people rather than goods. However, the term is far from precise. There were 590 million passenger cars worldwide (roughly one car for every eleven people) as of 2002.
The first bridges were spans made of wooden logs or planks and eventually stones, using a simple support and crossbeam arrangement. Most of these early bridges were very poorly built and could rarely support heavy weights. It was this inadequacy which led to the development of better bridges. The arch was first used by the Roman Empire for bridges and aqueducts, some of which still stand today. These arch based bridges could stand in conditions that would previously have swept any previous bridge away.An example is the Alcántara Bridge, built over the river Tagus, near Portugal. Most earlier bridges would have been swept away by the strong current. The Romans also used cement, which reduced the variation of strength found in natural stone. One type of cement, called pozzolana, consisted of water, lime, sand, and volcanic rock. Brick and mortar bridges were built after the Roman era, as the technology for cement was lost then later rediscovered.
Throughout most of history, the purpose of creating sculpture has been to produce works of art that are as permanent as is possible. So to that end, works were usually produced in durable and frequently, expensive materials, primarily bronze and stone such as marble, limestone, porphyry, and granite. More rarely, precious materials such as gold, silver, jade, and ivory were used for chryselephantine works. More common and less expensive materials were used for sculpture for wider consumption, including woods such as oak, boxwood (Buxus) and lime or linden (Tilia), terra cotta and other ceramics, and cast metals such as pewter and zinc (spelter).
A home is a place where a person or family lives, perhaps spends much of their time, or where a person is comfortable being. While a house (or other residential dwelling) is often referred to as a home, the concept of 'home' is broader than a physical dwelling. Home is often a place of refuge and safety, where worldly cares fade and the things and people that one loves becomes the focus. Many people think of home in terms of where they grew up, or a time rather than a place.
