Great Pyramid of Giza The Great Pyramid of Giza (also known as the Pyramid of Khufu or the Pyramid of Cheops) is the oldest and largest of the three pyramids in the Giza Necropolis bordering what is now El Giza, Egypt. It is the oldest of the Seven Wonders of the Ancient World, and the only one to remain largely intact. Based on a mark in an interior chamber naming the work gang and a reference to fourth dynasty Egyptian Pharaoh Khufu,[1][2] Egyptologists believe that the pyramid was built as a tomb over a 10 to 20-year period concluding around 2560 BC. Initially at 146.5 metres (481 feet), the Great Pyramid was the tallest man-made structure in the world for over 3,800 years. There are three known chambers inside the Great Pyramid. Transparent view of Khufu's pyramid from SE. History and description[edit] The pyramid remained the tallest man-made structure in the world for over 3,800 years,[8] unsurpassed until the 160-metre-tall (520 ft) spire of Lincoln Cathedral was completed c. 1300. Materials[edit]
Bibliotheca (Pseudo-Apollodorus) The Bibliotheca (Ancient Greek: Βιβλιοθήκη, Bibliothēkē, "library") is a compendium of myths and heroic legends, arranged in three books, generally dated to the first or second centuries AD.[1] It was known traditionally as the Library of Apollodorus, but the attribution is now regarded as false. The Bibliotheca has been called "the most valuable mythographical work that has come down from ancient times".[2] An epigram recorded by Photius expressed its purpose: It has the following not ungraceful epigram: 'Draw your knowledge of the past from me and read the ancient tales of learned lore. Look neither at the page of Homer, nor of elegy, nor tragic muse, nor epic strain. The brief and unadorned accounts of myth in the Bibliotheca have led some commentators to suggest that even its complete sections are an epitome of a lost work. A certain "Apollodorus" is indicated as author on some surviving manuscripts (Diller 1983). The first mention of the work is by Photius. Diller, Aubrey (1983).
Norse mythology An undead völva, a Scandinavian seeress, tells the spear-wielding god Odin of what has been and what will be in Odin and the Völva by Lorenz Frølich (1895) For the practices and social institutions of the Norse pagans, see Norse paganism Norse mythology, or Scandinavian mythology, is the body of mythology of the North Germanic people stemming from Norse paganism and continuing after the Christianization of Scandinavia and into the Scandinavian folklore of the modern period. The northernmost extension of Germanic mythology, Norse mythology consists of tales of various deities, beings, and heroes derived from numerous sources from both before and after the pagan period, including medieval manuscripts, archaeological representations, and folk tradition. Most of the surviving mythology centers on the plights of the gods and their interaction with various other beings, such as humanity and the jötnar, beings who may be friends, lovers, foes and/or family members of the gods. Sources[edit]
Ancient Egyptian technology Ancient Egyptian depiction of women engaged in mechanical rope making, the first graphic evidence of the craft, shown in the two lower rows of the illustration Technology in Dynastic Egypt[edit] Significant advances in ancient Egypt during the dynastic period include astronomy, mathematics, and medicine. Their geometry was a necessary outgrowth of surveying to preserve the layout and ownership of farmland, which was flooded annually by the Nile river. Paper and writing[edit] A section of the Egyptian Book of the Dead, which is written and drawn on papyrus The word paper comes from the Greek term for the ancient Egyptian writing material called papyrus, which was formed from beaten strips of papyrus plants. Egyptian hieroglyphs, a phonetic writing system, served as the basis for the Phoenician alphabet from which later alphabets were derived. The city of Alexandria retained preeminence for its records and scrolls with its library. Structures and construction[edit] Buildings[edit]
Sundial SSW facing, vertical declining sundial on Moot Hall, Aldeburgh, Suffolk, England. A combined analemmatic-equatorial sundial in Ann Morrison Park in Boise, Idaho, 43°36'45.5"N 116°13'27.6"W A sundial is a device that tells the time of day by the position of the Sun. In common designs such as the horizontal sundial, the sun casts a shadow from its style onto a surface marked with lines indicating the hours of the day. The style is the time-telling edge of the gnomon, often a thin rod or a sharp, straight edge. As the sun moves across the sky, the shadow-edge aligns with different hour-lines. Introduction[edit] There are different types of sundials. The shadow-casting object, known as a gnomon, may be a long thin rod, or other object with a sharp tip or a straight edge. With sundials using light to indicate time, a line of light may be formed by allowing the sun's rays through a thin slit or focusing them through a cylindrical lens. Apparent motion of the Sun[edit] [citation needed]
Traditional Chinese medicine Traditional medicine in China Traditional Chinese medicine (TCM) is an alternative medical practice drawn from traditional medicine in China. It has been described as "fraught with pseudoscience", with the majority of its treatments having no logical mechanism of action.[1][2] Medicine in traditional China encompassed a range of sometimes competing health and healing practices, folk beliefs, literati theory and Confucian philosophy, herbal remedies, food, diet, exercise, medical specializations, and schools of thought.[3] In the early twentieth century, Chinese cultural and political modernizers worked to eliminate traditional practices as backward and unscientific. The demand for traditional medicines in China has been a major generator of illegal wildlife smuggling, linked to the killing and smuggling of endangered animals.[10] History[edit] The Compendium of Materia Medica is a pharmaceutical text written by Li Shizhen (1518–1593 CE) during the Ming dynasty of China. Shang dynasty[edit]
Metallurgy Georgius Agricola, author of De re metallica, an important early work on metal extraction Metallurgy is a domain of materials science and materials engineering that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their mixtures, which are called alloys. Metallurgy is also the technology of metals: the way in which science is applied to the production of metals, and the engineering of metal components for use in products for consumers and manufacturers. The production of metals involves the processing of ores to extract the metal they contain, and the mixture of metals, sometimes with other elements, to produce alloys. Metallurgy is distinguished from the craft of metalworking. Metallurgy is subdivided into ferrous metallurgy (sometimes also known as black metallurgy) and non-ferrous metallurgy or colored metallurgy. Etymology and pronunciation[edit] History[edit] Gold headband from Thebes 750–700 BC Extraction[edit] Alloys[edit] [edit]
Gunpowder Gunpowder, also known as black powder, was the first chemical explosive and the only one known until the mid-19th century. It is a mixture of sulfur, charcoal, and potassium nitrate (saltpeter)—with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer.[2][3] Because of its burning properties and the amount of heat and gas volume that it generates, gunpowder has been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks. Gunpowder was, according to prevailing academic consensus, invented in the 9th century in China,[4] and the earliest record of a written formula for gunpowder appears in the 11th century Song Dynasty text, Wujing Zongyao.[5] This discovery led to the invention of fireworks and the earliest gunpowder weapons in China. Gunpowder is classified as a low explosive because of its relatively slow decomposition rate and consequently low brisance. History[edit] Early Chinese rocket China[edit] Middle East[edit] C.
Crystallography A crystalline solid: atomic resolution image of strontium titanate. Brighter atoms are Sr and darker ones are Ti. Crystallography is the science that examines the arrangement of atoms in solids (see crystal structure). The word "crystallography" derives from the Greek words crystallon "cold drop, frozen drop," with its meaning extending to all solids with some degree of transparency, and grapho "I write." In July 2012, the United Nations recognised the importance of the science of crystallography by proclaiming that 2014 would be the International Year of Crystallography.[1] X-ray crystallography is used to determine the structure of large biomolecules, such as proteins. Before the development of X-ray diffraction crystallography (see below), the study of crystals was based on their geometry. Crystallographic methods now depend on the analysis of the diffraction patterns of a sample targeted by a beam of some type. Theory[edit] Notation[edit] Technique[edit] Biology[edit] See also[edit]
Forge A blacksmith's coal forge Wooden smithy in Opole, Upper Silesia, Poland Types of forges[edit] Coal/coke/charcoal forge[edit] Standard coal forge Over thousands of years of forging, these devices have evolved in one form or another as the essential features of this type of forge:[citation needed] Tuyere — a pipe through which air can be forced into the fireBellows or blower — a means for forcing air into the tuyereHearth — a place where the burning fuel can be contained over or against the tuyere opening. During operation, fuel is placed in or on the hearth and ignited. A typical Scottish smithy at Auchentiber, North Ayrshire, Scotland. A blacksmith balances the fuel and air in the fire to suit particular kinds of work. In a typical coal forge, a firepot will be centered in a flat hearth. If a larger fire is necessary, the smith increases the air flowing into the fire as well as feeding and deepening the coke heart. Gas forge[edit] A gas forge typically uses propane or natural gas as the fuel.
Clock The clock is one of the oldest human inventions, meeting the need to consistently measure intervals of time shorter than the natural units: the day, the lunar month, and the year. Devices operating on several physical processes have been used over the millennia. A sundial shows the time by displaying the position of a shadow on a flat surface. There are a range of duration timers, a well-known example being the hourglass. Water clocks, along with the sundials, are possibly the oldest time-measuring instruments. A major advance occurred in Europe around 1300 with the invention of the escapement, which allowed construction of the first mechanical clocks, which used oscillating timekeepers like balance wheels.[3][4][5][6] Spring-driven clocks appeared during the 15th century. The study of timekeeping is known as horology. History[edit] Time-measuring devices[edit] Sundials[edit] Simple horizontal sundial Devices that measure duration, elapsed time and/or intervals[edit] Water clocks[edit]
Calendar A calendar is a system of organizing days for social, religious, commercial or administrative purposes. This is done by giving names to periods of time, typically days, weeks, months, and years. A date is the designation of a single, specific day within such a system. Periods in a calendar (such as years and months) are usually, though not necessarily, synchronized with the cycle of the sun or the moon. Many civilizations and societies have devised a calendar, usually derived from other calendars on which they model their systems, suited to their particular needs. A calendar is also a physical device (often paper). A calendar can also mean a list of planned events, such as a court calendar. The English word calendar is derived from the Latin word kalendae, which was the Latin name of the first day of every month.[1] Calendar systems[edit] A full calendar system has a different calendar date for every day. The simplest calendar system just counts time periods from a reference date.