Road Construction Methods have changed a lot since the first roads were built in about 4000 BC. Read on to learn more about road construction methods and procedures. In ancient times, river transport was much faster and easier than road transport. The Romans were one of the first to build stone paved roads in North…
Wattle and daub, in building construction, method of constructing walls in which vertical wooden stakes, or wattles, are woven with horizontal twigs and branches, and then daubed with clay or mud. This method is one of the oldest known for making a weatherproof structure. In England, Iron Age sites have been discovered with remains of circular dwellings constructed in this…
Tepee, also spelled tipi, conical tent most common to the North American Plains Indians. Although a number of Native American groups used similar structures during the hunting season, only the Plains Indians adopted tepees as year-round dwellings, and then only from the 17th century onward. At that time the Spanish introduction of horses, guns, and metal implements enabled Plains peoples to become mounted…
Yurt, also spelled yurta, Mongol ger, tentlike Central Asian nomad’s dwelling, erected on wooden poles and covered with skin, felt, or handwoven textiles in bright colours. The interior is simply furnished with brightly coloured rugs (red often predominating) decorated with geometric or stylized animal patterns. The knotted pile rug, first known from a nomad burial at the foot…
Machine, device, having a unique purpose, that augments or replaces human or animal effort for the accomplishment of physical tasks. This broad category encompasses such simple devices as the inclined plane, lever, wedge, wheel and axle, pulley, and screw (the so-called simple machines) as well as such complex mechanical systems as the modern automobile. simple machinesSix simple machines for transforming energy into work. The…
Humidity, the amount of water vapour in the air. It is the most variable characteristic of the atmosphere and constitutes a major factor in climate and weather. Atmospheric water vapour is an important factor in weather for several reasons. It regulates air temperature by absorbing thermal radiation both from the Sun and the Earth. Moreover, the higher the vapour content of the atmosphere, the more latent energy is…
Environment, the complex of physical, chemical, and biotic factors that act upon an organism or an ecological community and ultimately determine its form and survival. The Earth’s environment is treated in a number of articles. The major components of the physical environment are discussed in the articles atmosphere, climate, continental landform, hydrosphere, and ocean. The relationship between the principal systems and components of the environment,…
Concrete, in construction, structural material consisting of a hard, chemically inert particulate substance, known as aggregate (usually sand and gravel), that is bonded together by cement and water. concrete Among the ancient Assyrians and Babylonians, the bonding substance most often used was clay. The Egyptians developed a substance more closely resembling modern concrete by using lime and gypsum as binders. Lime (calcium oxide), derived from limestone, chalk, or (where…
Brick and tile, structural clay products, manufactured as standard units, used in building construction. The brick, first produced in a sun-dried form at least 6,000 years ago and the forerunner of a wide range of structural clay products used today, is a small building unit in the form of a rectangular block, formed from clay or shale…
Hide, the pelt taken from a cow, steer, or bull of the bovine species, from the pelt of a horse, or from the integument of some other large adult animal. The pelts of smaller animals are commonly called skins—namely, sheepskins, goatskins, calfskins, etc. For the preservation and tanning of hides . Tanning Tanning, chemical treatment of raw animal hide or…