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René Grillet De Roven
René Grillet de Roven, also René Grillet, was a French mechanic and watchmaker who designed a mechanical calculating machine in the 17th century. Biography Grillet came from Rouen in northwestern France, the capital city of Normandy. He served as watchmaker to King Louis XIV. In 1673 Grillet published a small book, ''Curiositez mathematiques de l'invention du Sr Grillet horlogeur a Paris'', in which he announced the invention of an arithmetical calculating machine. A few years later, in 1678, he wrote a short article in '' Le Journal des Sçavans'' describing the machine. According to Grillet, he was inspired by Blaise Pascal's work with calculating machines to combine the Pascaline with Napier's bones, and build a machine that could perform both addition and multiplication. Grillet displayed his machine at fairs in France and the Netherlands between 1673 and 1681. He tried to establish a business of manufacturing and selling calculating machines, with unclear success. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rouen
Rouen (, ; or ) is a city on the River Seine, in northwestern France. It is in the prefecture of Regions of France, region of Normandy (administrative region), Normandy and the Departments of France, department of Seine-Maritime. Formerly one of the largest and most prosperous cities of medieval Europe, the population of the metropolitan area () is 702,945 (2018). People from Rouen are known as ''Rouennais''. Rouen was the seat of the Exchequer of Normandy during the Middle Ages. It was one of the capitals of the Anglo-Normans, Anglo-Norman and Angevin kings of England, Angevin dynasties, which ruled both England and large parts of modern France from the 11th to the 15th centuries. From the 13th century onwards, the city experienced a remarkable economic boom, thanks in particular to the development of textile factories and river trade. Claimed by both the French and the English during the Hundred Years' War, it was on its soil that Joan of Arc was tried and burned alive on 30 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphometer
The graphometer, semicircle or semicircumferentor is a surveying instrument used for angle measurements. It consists of a semicircular wiktionary:Limb#Etymology 2, limb divided into 180 degrees and sometimes subdivided into minutes. The limb is subtended by the diameter with two sight (device), sights at its ends. In the middle of the diameter a "box and needle" (compass) is fixed. On the same middle the alidade with two other sights is fitted. The device is mounted on a Jacob's staff#Surveying, staff via a ball and socket joint. In effect the device is a half-circumferentor. For convenience, sometimes another half-circle from 180 to 360 degrees may be graduation (instrument), graduated in another line on the limb. Pages: vol. 1 p. 179 for "Graphometer", vol. 2 p. 50 for "Semi-Circle" The form was introduced in Philippe Danfrie's (Paris, 1597) and the term ''graphometer'' was popular with French Geodesist, geodesists. The preferable English-language terms were ''semicircle'' or ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineers From Rouen
Engineers, as practitioners of engineering, are professionals who invent, design, build, maintain and test machines, complex systems, structures, gadgets and materials. They aim to fulfill functional objectives and requirements while considering the limitations imposed by practicality, regulation, safety and cost. "Science is knowledge based on our observed facts and tested truths arranged in an orderly system that can be validated and communicated to other people. Engineering is the creative application of scientific principles used to plan, build, direct, guide, manage, or work on systems to maintain and improve our daily lives." The word ''engineer'' (Latin , the origin of the Ir. in the title of engineer in countries like Belgium, The Netherlands, and Indonesia) is derived from the Latin words ("to contrive, devise") and ("cleverness"). The foundational qualifications of a licensed professional engineer typically include a four-year bachelor's degree in an engineering disc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
17th-century Artisans
The 17th century lasted from January 1, 1601 (represented by the Roman numerals MDCI), to December 31, 1700 (MDCC). It falls into the early modern period of Europe and in that continent (whose impact on the world was increasing) was characterized by the Baroque cultural movement, the latter part of the Spanish Golden Age, the Dutch Golden Age, the French ''Grand Siècle'' dominated by Louis XIV, the Scientific Revolution, the world's first public company and megacorporation known as the Dutch East India Company, and according to some historians, the General Crisis. From the mid-17th century, European politics were increasingly dominated by the Kingdom of France of Louis XIV, where royal power was solidified domestically in the civil war of the Fronde. The semi-feudal territorial French nobility was weakened and subjugated to the power of an absolute monarchy through the reinvention of the Palace of Versailles from a hunting lodge to a gilded prison, in which a greatly expanded ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
French Watchmakers (people)
French may refer to: * Something of, from, or related to France ** French language, which originated in France ** French people, a nation and ethnic group ** French cuisine, cooking traditions and practices Arts and media * The French (band), a British rock band * "French" (episode), a live-action episode of ''The Super Mario Bros. Super Show!'' * ''Française'' (film), a 2008 film * French Stewart (born 1964), American actor Other uses * French (surname), a surname (including a list of people with the name) * French (tunic), a type of military jacket or tunic * French's, an American brand of mustard condiment * French (catheter scale), a unit of measurement * French Defence, a chess opening * French kiss, a type of kiss See also * France (other) * Franch, a surname * French Revolution (other) * French River (other), several rivers and other places * Frenching (other) * Justice French (other) Justice French may refer to: * C. G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plumb-bob
A plumb bob, plumb bob level, or plummet, is a weight, usually with a pointed tip on the bottom, suspended from a string and used as a vertical direction as a reference line, or plumb-line. It is a precursor to the spirit level and used to establish a vertical datum reference, datum. It is typically made of stone, wood, or lead, but can also be made of other metals. If it is used for decoration, it may be made of bone or ivory. The measuring instrument, instrument has been used since at least the time of ancient EgyptDenys A. Stocks. Experiments in Egyptian archaeology: stoneworking technology in Ancient Egypt'. Routledge; 2003. . p. 180. to ensure that constructions are "wikt:plumb, plumb", or vertical. It is also used in surveying, to establish the nadir (opposite of zenith) with respect to Gravity of Earth, gravity of a point in space. It is used with a variety of instruments (including Level (instrument), levels, theodolites, and tape measure, steel tapes) to set the in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Set Square
A set square or triangle (American English) is an object used in engineering and technical drawing, with the aim of providing a straightedge at a right angle or other particular planar angle to a baseline. Types The simplest form of set square is a triangular piece of transparent plastic (or formerly of polished wood) with the centre removed. More commonly the set square bears the markings of a ruler and a half circle protractor. The outer edges are typically bevelled. These set squares come in two usual forms, both right triangles: one with 90-45-45 degree angles, the other with 30-60-90 degree angles. Combining the two forms by placing the hypotenuses together will also yield 15° and 75° angles. They are often purchased in packs with protractors and compasses. Less commonly found is the adjustable set square. Here, the body of the object is cut in half and rejoined with a hinge marked with angles. Adjustment to the marked angle will produce any desired angl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protractor
A goniometer is an instrument that either measures an angle or allows an object to be rotated to a precise angular position. The term goniometry derives from two Greek words, γωνία (''gōnía'') 'angle' and μέτρον (''métron'') ' measure'. The protractor is a commonly used type in the fields of mechanics, engineering, and geometry. The first known description of a goniometer, based on the astrolabe, was by Gemma Frisius in 1538. Protractor A protractor is a measuring instrument, typically made of transparent plastic, for measuring angles. Some protractors are simple half-discs or full circles. More advanced protractors, such as the bevel protractor, have one or two swinging arms, which can be used to help measure the angle. Most protractors measure angles in degrees (°). Radian-scale protractors measure angles in radians. Most protractors are divided into 180 equal parts. Some precision protractors further divide degrees into arcminutes. A protractor divided ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hygrometer
A hair tension dial hygrometer with a nonlinear scale. A hygrometer is an instrument that measures humidity: that is, how much water vapor is present. Humidity measurement instruments usually rely on measurements of some other quantities, such as temperature, pressure, mass, and mechanical or electrical changes in a substance as moisture is absorbed. By calibration and calculation, these measured quantities can be used to indicate the humidity. Modern electronic devices use the temperature of condensation (called the dew point), or they sense changes in electrical capacitance or resistance. The maximum amount of water vapor that can be present in a given volume (at saturation) varies greatly with temperature; at low temperatures a lower mass of water per unit volume can remain as vapor than at high temperatures. Thus a change in the temperature changes the relative humidity. A prototype hygrometer was invented by Leonardo da Vinci in 1480. Major improvements occurred during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Normandy
Normandy (; or ) is a geographical and cultural region in northwestern Europe, roughly coextensive with the historical Duchy of Normandy. Normandy comprises Normandy (administrative region), mainland Normandy (a part of France) and insular Normandy (mostly the British Channel Islands). It covers . Its population in 2017 was 3,499,280. The inhabitants of Normandy are known as Normans; the region is the historic homeland of the Norman language. Large settlements include Rouen, Caen, Le Havre and Cherbourg-en-Cotentin, Cherbourg. The cultural region of Normandy is roughly similar to the historical Duchy of Normandy, which includes small areas now part of the departments of Mayenne and Sarthe. The Channel Islands (French: ''Îles Anglo-Normandes'') are also historically part of Normandy; they cover and comprise two bailiwicks: Bailiwick of Guernsey, Guernsey and Jersey, which are British Crown Dependencies. Normandy's name comes from the settlement of the territory by Vikings ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Napier's Bones
Napier's bones is a manually operated calculating device created by John Napier of Merchiston, Scotland for the calculation of products and quotients of numbers. The method was based on lattice multiplication, and also called ''rabdology'', a word invented by Napier. Napier published his version in 1617. It was printed in Edinburgh and dedicated to his patron Alexander Seton, 1st Earl of Dunfermline, Alexander Seton. Using the Multiplication table, multiplication tables embedded in the rods, multiplication can be reduced to addition operations and division (mathematics), division to Subtraction, subtractions. Advanced use of the rods can extract square roots. Napier's bones are not the same as logarithms, with which Napier's name is also associated, but are based on dissected multiplication tables. The complete device usually includes a base board with a rim; the user places Napier's rods and the rim to conduct multiplication or division. The board's left edge is divided into n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pascaline
A Pascaline signed by Pascal in 1652 Top view and overview of the entire mechanism. This version of Pascaline was for accounting. The pascaline (also known as the arithmetic machine or Pascal's calculator) 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, France. Magazine Nature, (1942) He designed the machine to add and subtract two numbers and to perform multiplication and division through repeated addition or subtraction. There were three versions of his calculator: one for accounting, one for surveying, and one for science. The accounting version represented the livre which was the currency in France at the time. The next dial to the right represented sols where 20 sols make 1 livre. The next, and right-most dial, represented deniers where 12 deniers make 1 sol. Pascal's calculator was especially successful in the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
