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Bhāskara's wheel was a hypothetical perpetual-motion machine design created around 1150 CE by the Indian mathematician Bhāskara II. The wheel consisted of curved or tilted spokes partially filled with mercury. [1] Once in motion, the mercury would flow from one side of the spoke to another, thus forcing the wheel to continue motion, in ...
Wheel graph. In the mathematical discipline of graph theory, a wheel graph is a graph formed by connecting a single universal vertex to all vertices of a cycle. A wheel graph with n vertices can also be defined as the 1- skeleton of an (n – 1)-gonal pyramid. Some authors [1] write Wn to denote a wheel graph with n vertices (n ≥ 4); other ...
Duplicating machines were the predecessors of modern document-reproduction technology. They have now been replaced by digital duplicators, scanners, laser printers and photocopiers, but for many years they were the primary means of reproducing documents for limited-run distribution. The duplicator was pioneered by Thomas Edison and David ...
Diagram illustrating the principles used by William Wallace's eidograph. The ancient Greek engineer Hero of Alexandria described pantographs in his work Mechanics. [1]In 1603, [2] Christoph Scheiner used a pantograph to copy and scale diagrams, and wrote about the invention over 27 years later, in "Pantographice seu Ars delineandi res quaslibet per parallelogrammum lineare seu cavum" (Rome 1631).
An early wheel made of a solid piece of wood. A wheel is a rotating component (typically circular in shape) that is intended to turn on an axle bearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating ...
Pascal's calculator (also known as the arithmetic machine or Pascaline) is a mechanical calculator invented by Blaise Pascal in 1642. Pascal was led to develop a calculator by the laborious arithmetical calculations required by his father's work as the supervisor of taxes in Rouen. [2] He designed the machine to add and subtract two numbers ...
The teeth are moved by a second wheel located inside the first and moved by a side lever. A pinwheel calculator is a class of mechanical calculator described as early as 1685, and popular in the 19th and 20th century, calculating via wheels whose number of teeth were adjustable. These wheels, also called pinwheels, could be set by using a side ...
e. The Enigma machine is a cipher device developed and used in the early- to mid-20th century to protect commercial, diplomatic, and military communication. It was employed extensively by Nazi Germany during World War II, in all branches of the German military. The Enigma machine was considered so secure that it was used to encipher the most ...