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. Originally, the Great Pyramid was covered by casing stones that formed a smooth outer surface; what is seen today is the underlying core structure. There are three known chambers inside the Great Pyramid. Transparent view of Khufu's pyramid from SE. History and description[edit] Materials[edit] Casing stones[edit] Casing stone
Lucy the Elephant Elephant hotel redirects here. For the National Historic Landmark located in Somers, New York, see Elephant Hotel. Lucy the Elephant is a six-story elephant-shaped example of novelty architecture, constructed of wood and tin sheeting in 1881 by James V. Today, Lucy is a tourist attraction. 1800s[edit] In 1881, the U.S. Lafferty brought real estate customers up a narrow spiral staircase from within the elephant's body to the howdah, where he could point out real estate parcels available for sale.[5] Lucy's head shape identifies the building as an Asian Elephant, and its tusks as a male. The structure was sold to Anton Gertzen of Philadelphia in 1887 and remained in the Gertzen family until 1970. Lafferty built at least two more elephant-shaped buildings, though neither survives. 1900s[edit] Over the years, Lucy had served as a restaurant, business office, cottage, and tavern (the last closed by Prohibition). By the 1960s, Lucy had fallen into disrepair and was scheduled for demolition.
Pan-American Highway The Pan American Highway from Prudhoe Bay, Alaska to Ushuaia, Argentina, with selected official and unofficial routes shown through the U.S.A. and Canada. The Pan-American Highway (Portuguese: Rodovia / Auto-estrada Pan-americana, Spanish: Autopista / Carretera / Ruta Panamericana) is a network of roads measuring about 48,000 kilometres (30,000 mi) in total length, except for a rainforest break of approximately 100 km (60 mi), called the Darién Gap, the road links almost all of the mainland nations of the Americas in a connected highway system. According to Guinness World Records, the Pan-American Highway is the world's longest "motorable road". However, because of the Darién Gap, it is not possible to cross between South America and Central America by traditional motor vehicle. Jake Silverstein, writing in 2006, described the Pan-American Highway as "a system so vast, so incomplete, and so incomprehensible it is not so much a road as it is the idea of Pan-Americanism itself".[1]
the Tricorder project - Science Tricorder Mark 2 The Science Tricorder Mark 2 was a wonderful adventure of discovery to develop. It's my pleasure to be able to share it with you. To introduce you to the Tricorder project, I'd like to begin with a story from the development of the very first Tricorder that I built. More educational discoveries came quickly — from finding all the heat leaks from different building materials in my graduate student apartment in a century home, to how much humidity is exhaled in a breath. Again, it is my pleasure to be able to share this with you. Sensors The Science Tricorder Mark 2 prototype sensor board contains ten different sensing modalities, organized into three main categories: atmospheric sensors, electromagnetic sensors, and spatial sensors. The sensing modalities and specific sensors used on this device, as well as some approximate summary specifications, are as follows: Sensiron SHT11 Atmospheric Temperature and Humidity -40°C to +120°C, ± 0.5°C accuracy ± 0.1°C repeatability Hardware
Matryoshka doll Set of Matryoshka dolls in order of size Matryoshka doll taken apart A matryoshka doll (Russian: матрёшка, IPA: [mɐˈtrʲɵʂkə] ( ), matrëška), also known as Russian nesting/nested doll, refers to a set of wooden dolls of decreasing size placed one inside the other. The first Russian nested doll set was carved in 1890 by Vasily Zvyozdochkin from a design by Sergey Malyutin, who was a folk crafts painter at Abramtsevo. Design[edit] Church-themed matryoshka A set of matryoshkas consist of a wooden figure which separates, top from bottom, to reveal a smaller figure of the same sort inside, which has, in turn, another figure inside of it, and so on. The word "matryoshka" (матрёшка), literally "little matron", is a diminutive form of the Russian female first name "Matryona" (Матрёна).[1] History[edit] Zvyozdochkin and Malyutin were inspired by a doll from Honshu, the main island of Japan. Themes[edit] During Perestroika, the leaders of the Soviet Union became a common theme depicted on matryoshkas.
Cafe au Go Go The Cafe au Go Go was a Greenwich Village night club located in the basement of 152 Bleecker Street. The club featured many well known musical groups, folksingers and comedy acts between the opening in February 1964 until closing in October 1969. The club was originally owned by Howard Solomon who sold it in June 1969 to Moses Baruch. Legal problems[edit] Comedian Lenny Bruce and the club's owner, Howard Solomon, were arrested there on obscenity charges in 1964. On December 23, 2003,[8][9] 37 years after his death, Bruce was granted a posthumous pardon for his obscenity conviction by New York Governor George Pataki,[10] following a petition filed by Ronald Collins and David Skover with Robert Corn-Revere as counsel, the petition having been signed by several stars such as Robin Williams. Au Go Go Singers and Comedians[edit] When the Cafe au Go Go finally locked its doors for good, the now-famous Stephen Stills was a featured performer at the gala closing.[11] See also[edit] Cafe Au Go Go
Stepped Reckoner Replica of Leibniz's Stepped Reckoner in the Deutsches Museum. [...] it is beneath the dignity of excellent men to waste their time in calculation when any peasant could do the work just as accurately with the aid of a machine. The Step Reckoner (or Stepped Reckoner) was a digital mechanical calculator invented by German mathematician Gottfried Wilhelm Leibniz around 1672 and completed in 1694.[1] The name comes from the translation of the German term for its operating mechanism; staffelwalze meaning 'stepped drum'. It was the first calculator that could perform all four arithmetic operations: addition, subtraction, multiplication and division.[2] Its intricate precision gearwork, however, was somewhat beyond the fabrication technology of the time; mechanical problems, in addition to a design flaw in the carry mechanism, prevented the machines from working reliably.[3][4] Description[edit] Leibniz wheel In the position shown, the counting wheel meshes with 3 of the 9 Leibniz wheel's teeth
Raising of Chicago During the 1850s and 1860s engineers carried out a piecemeal raising of the level of central Chicago. Streets, sidewalks and buildings were either built up, relocated, or physically raised on hydraulic jacks or jackscrews. The work was funded by private property owners and public funds. Background[edit] Advertisement in the Chicago Daily Tribune, 1858.[1] During the 19th century, the elevation of the Chicago area was not much higher than the shorelines of Lake Michigan, so for many years there was little or no naturally occurring drainage from the city surface. The crisis forced the city's engineers and aldermen to take the drainage problem seriously and after many heated discussions[6][7]—and following at least one false start—a solution eventually materialized. Earliest raising of a brick building[edit] The Row on Lake Street[edit] Raising a block of buildings on Lake Street The Tremont House[edit] The Robbins Building[edit] Hydraulic raising of the Franklin House[edit] See also[edit]
Prague astronomical clock Prague astronomical clock The Prague astronomical clock, or Prague orloj (Czech: Pražský orloj [praʃskiː orloj]), is a medieval astronomical clock located in Prague, the capital of the Czech Republic. The clock was first installed in 1410, making it the third-oldest astronomical clock in the world and the oldest one still operating. Description[edit] History[edit] The oldest part of the Orloj, the mechanical clock and astronomical dial, dates back to 1410 when it was made by clockmaker Mikuláš of Kadaň and Jan Šindel, the latter a professor of mathematics and astronomy at Charles University. Formerly, it was believed that the Orloj was constructed in 1490 by clockmaster Jan Růže (also called Hanuš); this is now known to be a historical mistake. In 1552 it was repaired by Jan Taborský (ca1500–1572), master clockmaker of Klokotská Hora, who also wrote a report of the clock where he mentioned Hanuš as maker of this clock. 600th anniversary[edit] 605th anniversary[edit] Astronomical dial[edit]