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Barograph
A barograph is a barometer that records the barometric pressure over time in graphical form. This instrument is also used to make a continuous recording of atmospheric pressure. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the vertical displacement of the pen is proportional to the changes in the atmospheric pressure. Development Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an aneroid cell.Gloria Clifton (2004)"Cumming, Alexander (1731/2–1814)", '' Oxford Dictionary of National Biography'', Oxford University Press. (Subscription or UK public library membership required) Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so called Vidie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barograph 01
A barograph is a barometer that records the barometric pressure over time in graphical form. This instrument is also used to make a continuous recording of atmospheric pressure. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the vertical displacement of the pen is proportional to the changes in the atmospheric pressure. Development Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an Manometer#Aneroid, aneroid cell.Gloria Clifton (2004)"Cumming, Alexander (1731/2–1814)", ''Oxford Dictionary of National Biography'', Oxford University Press. (Subscription or UK public library membership required) Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barograph 02
A barograph is a barometer that records the barometric pressure over time in graphical form. This instrument is also used to make a continuous recording of atmospheric pressure. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the vertical displacement of the pen is proportional to the changes in the atmospheric pressure. Development Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an aneroid cell.Gloria Clifton (2004)"Cumming, Alexander (1731/2–1814)", ''Oxford Dictionary of National Biography'', Oxford University Press. (Subscription or UK public library membership required) Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so called Vidie-cans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barograph
A barograph is a barometer that records the barometric pressure over time in graphical form. This instrument is also used to make a continuous recording of atmospheric pressure. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the vertical displacement of the pen is proportional to the changes in the atmospheric pressure. Development Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an aneroid cell.Gloria Clifton (2004)"Cumming, Alexander (1731/2–1814)", '' Oxford Dictionary of National Biography'', Oxford University Press. (Subscription or UK public library membership required) Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so called Vidie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barograph 03
A barograph is a barometer that records the barometric pressure over time in graphical form. This instrument is also used to make a continuous recording of atmospheric pressure. The pressure-sensitive element, a partially evacuated metal cylinder, is linked to a pen arm in such a way that the vertical displacement of the pen is proportional to the changes in the atmospheric pressure. Development Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an aneroid cell.Gloria Clifton (2004)"Cumming, Alexander (1731/2–1814)", ''Oxford Dictionary of National Biography'', Oxford University Press. (Subscription or UK public library membership required) Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so called Vidie-cans ... [...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 "me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Cumming
Alexander Cumming FRSE (sometimes referred to as Alexander Cummings; 1733 – 8 March 1814) was a Scottish watchmaker and instrument inventor, who was the first to patent a design of the flush toilet in 1775, which had been pioneered by Sir John Harington, but without solving the problem of foul smells. As well as improving the flush mechanism, Cummings included an S-trap (or bend) to retain water permanently within the waste pipe, thus preventing sewer gases from entering buildings. Most modern flush toilets still include a similar trap. Early life Cumming was a mathematician and mechanic as well as a watchmaker. Little is known of his early life. He was born in Edinburgh in 1733, the son of James Cumming of Duthil. He is recorded as having been apprenticed to an Edinburgh watchmaker. Career In the 1750s he was employed by Archibald Campbell, 3rd Duke of Argyll, at Inverary as an organ builder as well as a clockmaker. After his move to England he continued to work in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manometer
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure mechanically are called pressure gauges, vacuum gauges or compound gauges (vacuum & pressure). The widely used Bourdon gauge is a mechanical device, which both measures and indicates and is probably the best known type of gauge. A vacuum gauge is used to measure pressures lower than the ambient atmospheric pressure, which is set as the zero point, in negative values (for instance, −1 bar or −760 mmHg equals total vacuum). Most gauges measure pressure relative to atmospheric pressure as the zero point, so this form of reading is simply referred to as "gauge pressure". However, anything greater than total vacuum is technically a form of pressure. For very low pres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weather Forecast
Weather forecasting is the application of science and technology to predict the conditions of the atmosphere for a given location and time. People have attempted to predict the weather informally for millennia and formally since the 19th century. Weather forecasts are made by collecting quantitative data about the current state of the atmosphere, land, and ocean and using meteorology to project how the atmosphere will change at a given place. Once calculated manually based mainly upon changes in barometric pressure, current weather conditions, and sky condition or cloud cover, weather forecasting now relies on computer-based models that take many atmospheric factors into account. Human input is still required to pick the best possible forecast model to base the forecast upon, which involves pattern recognition skills, teleconnections, knowledge of model performance, and knowledge of model biases. The inaccuracy of forecasting is due to the chaotic nature of the atmosphere, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knurling
Knurling is a manufacturing process, typically conducted on a lathe, whereby a pattern of straight, angled or crossed lines is rolled into the material. Etymology The terms ''knurl'' and ''knurled'' are from an earlier ''knur'' ‘knot in wood’ and the diminutive ''-le'', from Middle English ''knaur'' or ''knarre'' ‘knot in wood; twisted rock; crag’. This descends from Old English ''cnearra'' but the vowel in Middle English may have been influenced by Old Norse ''knǫrr'' ‘merchant ship’ which was known as ''cnearr'' in Old English. The modern ''gnarl'' is a back-formation of ''gnarled'' which itself is first attested in Shakespeare’s works and is apparently a variant of ''knurled''. Uses The operation is performed for producing indentations on a part of a workpiece. Knurling allows hands or fingers to get a better grip on the knurled object than would be provided by the originally smooth metal surface. Occasionally, the knurled pattern is a series of straig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negretti And Zambra
Negretti and Zambra (active 1850 – c. 1985) was a company that produced scientific and optical instruments and also operated a photographic studio based in London. History Henry Negretti (1818–1879) and Joseph Zambra (1822–1897) formed a partnership in 1850, thereby founding the firm which would eventually be appointed opticians and scientific instrument makers to Her Majesty Queen Victoria, Prince Albert and King Edward VII, the Royal Observatory and the British Admiralty. Henry (Enrico Angelo Lodovico) Negretti was born in Como, Italy. Joseph Warren Zambra was born in Saffron Walden, Essex the son of Joseph Cezare Zambra and Phyllis Warren. When the Crystal Palace was re-erected in Sydenham in 1854, ''Negretti and Zambra'' became the official photographers of the Crystal Palace Company, which allowed them to photograph the interior and grounds of the new building. The firm made use of this access to produce a number of stereographs. In 1856 ''Negretti and Zambr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Gliding Commission
The International Gliding Commission (IGC) is the international governing body for the sport of gliding. It is governed by meetings of delegates from national gliding associations. It is one of several Air Sport Commissions (ASC) of the Fédération Aéronautique Internationale (FAI), or "World Air Sports Federation". FAI is the world body for sporting aviation and the certification of world records for aeronautics and astronautics and was founded in 1905. When the IGC was founded in 1932, it was called CIVV (Commission Internationale de Vol à Voile) and has also been called CVSM (Commission de Vol Sans Moteur). It is the FAI commission responsible for the international competitions, records and badges that apply to gliders and motor gliders. The term "sailplanes" is sometimes used. Hang gliders and paragliders have a separate body called the FAI CIVL Commission, which stands for "Commission Internationale de Vol Libre". The World Gliding Championships are organised every tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Positioning System
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite systems (GNSS) that provides geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. It does not require the user to transmit any data, and operates independently of any telephonic or Internet reception, though these technologies can enhance the usefulness of the GPS positioning information. It provides critical positioning capabilities to military, civil, and commercial users around the world. Although the United States government created, controls and maintains the GPS system, it is freely accessible to anyone with a GPS receiver. The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
