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Bathymeter
A bathometer (also bathymeter) is an instrument for measuring water depth. It was previously used mainly in oceanographical studies, but is rarely employed nowadays. The term originates from Greek ''βαθύς'' (''bathys''), "deep" and ''μέτρον'' (''métron''), "measure". History The earliest idea for a bathometer is due to Leon Battista Alberti (1404–1472) who sunk a hollow sphere attached to some ballast with a hook. When the ball reached the bottom it detached from the ballast and resurfaced. The depth was determined (rather inaccurately) by the time it took to surface. Jacob Perkins (1766–1849) proposed a bathometer based on the compressibility of water. In this instrument the movement of a piston compressing a body of water enclosed in its cylinder is dependent on the pressure of the water outside the cylinder, and hence its depth. The amount the piston moved can be measured when it is returned to the surface. A bathometer that did not need to be submerged ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Instrument
A scientific instrument is a device or tool used for scientific purposes, including the study of both natural phenomena and theoretical research. History Historically, the definition of a scientific instrument has varied, based on usage, laws, and historical time period. Before the mid-nineteentcenturysuch tools were referred to as "natural philosophical" or "philosophical" apparatus and instruments, and older tools from antiquity to the Middle Ages (such as the astrolabe and pendulum clock) defy a more modern definition of "a tool developed to investigate nature qualitatively or quantitatively." Scientific instruments were made by instrument makers living near a center of learning or research, such as a university or research laboratory. Instrument makers designed, constructed, and refined instruments for purposes, but if demand was sufficient, an instrument would go into production as a commercial product. In a description of the use of the eudiometer by Jan Ingenhousz to show ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanography
Oceanography (), also known as oceanology and ocean science, is the scientific study of the oceans. It is an Earth science, which covers a wide range of topics, including ecosystem dynamics; ocean currents, waves, and geophysical fluid dynamics; plate tectonics and the geology of the sea floor; and fluxes of various chemical substances and physical properties within the ocean and across its boundaries. These diverse topics reflect multiple disciplines that oceanographers utilize to glean further knowledge of the world ocean, including astronomy, biology, chemistry, climatology, geography, geology, hydrology, meteorology and physics. Paleoceanography studies the history of the oceans in the geologic past. An oceanographer is a person who studies many matters concerned with oceans, including marine geology, physics, chemistry and biology. History Early history Humans first acquired knowledge of the waves and currents of the seas and oceans in pre-historic times. Observations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greek Language
Greek ( el, label=Modern Greek, Ελληνικά, Elliniká, ; grc, Ἑλληνική, Hellēnikḗ) is an independent branch of the Indo-European family of languages, native to Greece, Cyprus, southern Italy (Calabria and Salento), southern Albania, and other regions of the Balkans, the Black Sea coast, Asia Minor, and the Eastern Mediterranean. It has the longest documented history of any Indo-European language, spanning at least 3,400 years of written records. Its writing system is the Greek alphabet, which has been used for approximately 2,800 years; previously, Greek was recorded in writing systems such as Linear B and the Cypriot syllabary. The alphabet arose from the Phoenician script and was in turn the basis of the Latin, Cyrillic, Armenian, Coptic, Gothic, and many other writing systems. The Greek language holds a very important place in the history of the Western world. Beginning with the epics of Homer, ancient Greek literature includes many works of lasting impo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leon Battista Alberti
Leon Battista Alberti (; 14 February 1404 – 25 April 1472) was an Italian Renaissance humanist author, artist, architect, poet, priest, linguist, philosopher, and cryptographer; he epitomised the nature of those identified now as polymaths. He is considered the founder of Western cryptography, a claim he shares with Johannes Trithemius. Although he often is characterized exclusively as an architect, as James Beck has observed, "to single out one of Leon Battista's 'fields' over others as somehow functionally independent and self-sufficient is of no help at all to any effort to characterize Alberti's extensive explorations in the fine arts". Although Alberti is known mostly for being an artist, he was also a mathematician of many sorts and made great advances to this field during the fifteenth century. The two most important buildings he designed are the churches of San Sebastiano (1460) and Sant'Andrea (1472), both in Mantua. Alberti's life was described in Giorgio Vasari's ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jacob Perkins
Jacob Perkins (9 July 1766 – 30 July 1849) was an American inventor, mechanical engineer and physicist. Born in Newburyport, Massachusetts, Perkins was apprenticed to a goldsmith. He soon made himself known with a variety of useful mechanical inventions and eventually had twenty-one American and nineteen English patents. He is known as the father of the refrigerator. He was elected a Fellow of the American Academy of Arts and Sciences in 1813 and a member of the American Philosophical Society in 1819. Early life Jacob went to school in Newburyport until he was twelve and then was apprenticed to a goldsmith in Newburyport named Davis. Mr. Davis died three years later and the fifteen-year-old Jacob continued the business of making gold beads and added the manufacture of shoe buckles. When he was twenty-one he was employed by the master of the Massachusetts mint to make a die for striking copper pennies bearing an eagle and an Indian. Innovations Nail machines In 1790, at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Stewart Traill
Thomas Stewart Traill (29 October 1781 – 30 July 1862) was a British physician, chemist, meteorologist, zoologist and scholar of medical jurisprudence. He was the grandfather of the physicist, meteorologist and geologist Robert Traill Omond FRSE (1858-1914). Early life Traill was born at Kirkwall in Orkney, the son of the Rev Thomas Traill (died 1782), the minister in Kirkwall, and his wife Lucia. His father died the year after he was born. He studied medicine at the University of Edinburgh, gaining his doctorate (MD) in 1802. He was elected a Fellow of the Royal Society of Edinburgh in 1819. His proposers were Robert Jameson, John Murray, Lord Murray, and Thomas Charles Hope. He was Curator of the Society's museum from 1834 to 1856. He practised medicine for 30 years in Liverpool, and was a founder of the Royal Institution of Liverpool, the Liverpool Mechanics' Institution and the Literary and Philosophical Society of Liverpool. He became acquainted with the Arctic exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Siemens
Sir Carl Wilhelm Siemens (4 April 1823 – 19 November 1883), anglicised to Charles William Siemens, was a German-British electrical engineer and businessman. Biography Siemens was born in the village of Lenthe, today part of Gehrden, near Hanover where his father, Christian Ferdinand Siemens (31 July 1787 – 16 January 1840), a tenant farmer, farmed an estate belonging to the Crown. The Siemens family is an old family of Goslar which has been documented since 1384. His mother was Eleonore Deichmann (1792–8 July 1839), and William, or Carl Wilhelm, was the fourth son of a family of fourteen children. Of his siblings, Ernst Werner Siemens, the fourth child, became a famous electrician and was associated with William in many of his inventions. He was also the brother of Carl Heinrich von Siemens and a cousin of Alexander Siemens. On 23 July 1859, Siemens was married at St James's, Paddington, to Anne Gordon—the youngest daughter of Mr Joseph Gordon, Writer to the Signet, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Telegraph
Electrical telegraphs were point-to-point text messaging systems, primarily used from the 1840s until the late 20th century. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called ''telegraphs'', that were devised to communicate text messages quicker than physical transportation. Electrical telegraphy can be considered to be the first example of electrical engineering. Text telegraphy consisted of two or more geographically separated stations, called telegraph offices. The offices were connected by wires, usually supported overhead on utility poles. Many different electrical telegraph systems were invented, but the ones that became widespread fit into two broad categories. The first category consists of needle telegraphs in which a needle pointer is made to move electromagnetically with an electric current sent down the telegraph line. Early systems used multiple needles requiring multiple wires. The first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barometer
A barometer is a scientific instrument that is used to measure air pressure in a certain environment. Pressure tendency can forecast short term changes in the weather. Many measurements of air pressure are used within surface weather analysis to help find surface troughs, pressure systems and frontal boundaries. Barometers and pressure altimeters (the most basic and common type of altimeter) are essentially the same instrument, but used for different purposes. An altimeter is intended to be used at different levels matching the corresponding atmospheric pressure to the altitude, while a barometer is kept at the same level and measures subtle pressure changes caused by weather and elements of weather. The average atmospheric pressure on the earth's surface varies between 940 and 1040 hPa (mbar). The average atmospheric pressure at sea level is 1013 hPa (mbar). Etymology The word ''barometer'' is derived from the Ancient Greek (), meaning "weight", and (), meaning "measure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Submarine Telegraph Cable
A submarine communications cable is a cable laid on the sea bed between land-based stations to carry telecommunication signals across stretches of ocean and sea. The first submarine communications cables laid beginning in the 1850s carried telegraphy traffic, establishing the first instant telecommunications links between continents, such as the first transatlantic telegraph cable which became operational on 16 August 1858. Subsequent generations of cables carried telephone traffic, then data communications traffic. Modern cables use optical fibre technology to carry digital data, which includes telephone, Internet and private data traffic. Modern cables are typically about in diameter and weigh around for the deep-sea sections which comprise the majority of the run, although larger and heavier cables are used for shallow-water sections near shore. Submarine cables first connected all the world's continents (except Antarctica) when Java was connected to Darwin, Northern Terri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth Sounding
Depth sounding, often simply called sounding, is measuring the depth of a body of water. Data taken from soundings are used in bathymetry to make maps of the floor of a body of water, such as the seabed topography. Soundings were traditionally shown on nautical charts in fathoms and feet. The National Oceanic and Atmospheric Administration (NOAA), the agency responsible for bathymetric data in the United States, still uses fathoms and feet on nautical charts. In other countries, the International System of Units (metres) has become the standard for measuring depth. Terminology "Sounding" derives from the Old English ''sund'', meaning "swimming, water, sea"; it is not related to the word ''sound'' in the sense of noise or tones, but to ''sound'', a geographical term. Traditional terms for soundings are a source for common expressions in the English language, notably "deep six" (a sounding of 6 fathoms). On the Mississippi River in the 1850s, the leadsmen also used old-fashione ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientific Instruments
A scientific instrument is a device or tool used for scientific purposes, including the study of both natural phenomena and theoretical research. History Historically, the definition of a scientific instrument has varied, based on usage, laws, and historical time period. Before the mid-nineteentcenturysuch tools were referred to as "natural philosophical" or "philosophical" apparatus and instruments, and older tools from antiquity to the Middle Ages (such as the astrolabe and pendulum clock) defy a more modern definition of "a tool developed to investigate nature qualitatively or quantitatively." Scientific instruments were made by instrument makers living near a center of learning or research, such as a university or research laboratory. Instrument makers designed, constructed, and refined instruments for purposes, but if demand was sufficient, an instrument would go into production as a commercial product. In a description of the use of the eudiometer by Jan Ingenhousz to show ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
