Their equipment was a plumb line—a piece of cord with a lead weight at the bottom.
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Its southern latitude disguises just how far west the shipping channel reaches — far enough to catch a plumb line dropped from Cleveland.
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There is a lot to like about Trump, but politics is more than personality; it is about a leader's personal plumb line that guides his or her thoughts and actions.
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"My views as a Christian means there's moral plumb line that I'm fighting to adhere to ... it's not say this is the way the country's going to run and things are going to be," Lecrae said.
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A self-described "fitness fanatic" who declined to give her age ("I don't tell; I'm a lady," she said), Ms. Jah is slim and not quite 5-foot-2, but with her plumb line posture, coiled braids and forceful energy, she looms larger.
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Perhaps I've read too many thrillers, but as I gazed up at this solemnly joyous creation, I imagined a plumb line dropping from the tiles of Christ's outstretched hand and coming to rest, magically, on the exact spot where the menorah had been stashed — fanciful, but not impossible.
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Two additional exhibitions will give further context to his legacy: Organized by LACMA and held at the Charles White Elementary School where he taught, Life Model: Charles White and His Students will explore his role as an educator, while Plumb Line: Charles White and the Contemporary at the California African American Museum features contemporary artists whose work resonates with White's.
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The plumb line then marked what hour of the day it was.
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'Breger, Louis (2000) Freud: Darkness in the Midst of Vision. John Wiley & Sons. . p. 431 Jacques Lacan called 'Anna Freud the plumb line of psychoanalysis. 'Well, the plumb line doesn't make a building ... [but] it allows us to gauge the vertical of certain problems.
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A gallery and a square are named after Rejt in Louny. There is also a 20th-century statue of Benedikt Rejt holding a plumb line.
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Clement of Alexandria, Stromata, vi. 4 The astrologer's instruments (horologium and palm) are a plumb line and sighting instrument. They have been identified with two inscribed objects in the Berlin Museum; a short handle from which a plumb line was hung, and a palm branch with a sight-slit in the broader end. The latter was held close to the eye, the former in the other hand, perhaps at arm's length.
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Clement of Alexandria, Stromata, vi. 4 The Astrologer's instruments (horologium and palm) are a plumb line and sighting instrument. They have been identified with two inscribed objects in the Berlin Museum; a short handle from which a plumb line was hung, and a palm branch with a sight-slit in the broader end. The latter was held close to the eye, the former in the other hand, perhaps at arm's length.
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The vertical deflection (VD), also known as deflection of the plumb line and astro-geodetic deflection, at a point on the Earth is a measure of how far the gravity direction (plumb line) has been shifted by local mass anomalies such as nearby mountains. They are widely used in geodesy, for surveying networks and for geophysical purposes. The vertical deflection are the angular components between the true zenith (plumb line) and the line perpendicular to the surface of the reference ellipsoid chosen to approximate the Earth's sea- level surface. VDs are caused by mountains and by underground geological irregularities and can amount to angles of 10″ (flat areas) or 20–50″ (alpine terrain).
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For a spinning earth, the plumb line deviates from the radial direction as a function of latitude. Only at the North and South Poles does the plumb line align with the local radius. The situation is actually even more complicated because earth is not a homogeneous smooth sphere. It is a non homogeneous, non spherical, knobby planet in motion, and the vertical not only need not lie along a radial, it may even be curved and be varying with time.
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Until the modern age, plumb bobs were used on most tall structures to provide vertical datum lines for the building measurements. A section of the scaffolding would hold a plumb line, which was centered over a datum mark on the floor. As the building proceeded upward, the plumb line would also be taken higher, still centered on the datum. Many cathedral spires, domes and towers still have brass datum marks inlaid into their floors, which signify the center of the structure above.
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Students of figure drawing will also make use of a plumb line to find the vertical axis through the center of gravity of their subject and lay it down on paper as a point of reference. The device used may be purpose-made plumb lines, or simply makeshift devices made from a piece of string and a weighted object, such as a metal washer. This plumb line is important for lining up anatomical geometries and visualizing the subject's center of balance.
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A plumb bob, or plummet, is a weight, usually with a pointed tip on the bottom, suspended from a string and used as a vertical reference line, or plumb-line. It is essentially the vertical equivalent of a "water level".
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From the anterior/posterior view this plumb line should run vertically down the midline of the body dividing it symmetrically into right and left halves indicating even weight distribution on left and right sides. From the sagittal view the plumb line should bisect the ear, odontoid process of C2, the cervical vertebral bodies, the center of the glenohumeral joint, the lumbar vertebral bodies, the center of the acetabulum, just posterior to the patella, and through the tarsals of the feet. This sagittal line of reference theoretically indicates even distribution of weight between the front and the back of the body.
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Schneemann along with Yves Klein in France, and Yayoi Kusama, Charlotte Moorman, and Yoko Ono in New York City were pioneers of performance based works of art, that often entailed nudity. Schneemann began work on the next film, Plumb Line, in her Autobiographical Trilogy in 1968. The film opens with a still shot of a man's face with a plumb line in front of it before the entire image begins to burn. Various images including Schneemann and the man appear in different quadrants of the frame while a discombobulating soundtrack consisting of music, sirens, and cat noises among other things play in the background.
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Diagram showing the relationship between the zenith, the nadir, and different types of horizon. Note that the zenith is opposite the nadir. The zenith is an imaginary point directly "above" a particular location, on the imaginary celestial sphere. "Above" means in the vertical direction (plumb line) opposite to the gravity direction at that location (nadir).
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This proved to be an excellent heading, as his Torpedo Eight squadron flew directly to the enemy carrier group's location "as though on a plumb line".Gay p. 113 They did so with no supporting fighters. On their way Waldron's Torpedo Eight happened to get picked up by Enterprises VF-6 fighter squadron flying several thousand feet above them.
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It suggested suitable trees for each monastic layout. It gave advice on the preparation and application of glues, pigments and pastes, and on the carving of elephants and horses, indicating the correct proportions of these animals. It even gave instructions on how to obtain measurements using the plumb line. There were auspicious times, auspicious materials and auspicious lengths.
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These are referred to as vertical or height datums. For every point on Earth, the local direction of gravity or vertical direction, materialized with the plumb line, is perpendicular to the geoid. On this is based a method, astrogeodetic levelling, for deriving the local figure of the geoid by measuring deflections of the vertical by astronomical means over an area.
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The leaning tower, 78 ft high, gets a lot of attention from tourists. Apparently if a plumb line is dropped from the north side of the tower it would fall 3 feet away from the building. This major leaning is believed to be caused by the poor foundations. During the 18th century a light was placed on the tower to guide fishing boats into the harbour.
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Gilbert's design used the same frame as a railroad bridge, but rotated vertically. The Tower Building was initially greeted with great skepticism, with members of the public predicting it would blow over. This prompted Gilbert to scale the building in the middle of an 1889 hurricane to demonstrate with a plumb line that the building was not vibrating. The building was razed in 1914.
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In architecture such as the Great Bath, bitumen was used for waterproofing. The Use of bitumen has been attested as early as the Mehrgarh period, one of the earliest uses in the world as well. The remarkable vertical alignment of the building indicates the use of a Plumb line. The bricks were produced in a standardized ratio of 4:2:1, found throughout the Indus Valley Civilization.
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The Stgw. 57 bipod legs are marked for use as an inclinometer for aiming rifle grenades at various ranges with and without an additional booster-charged rifle grenade. For such indirect rifle grenade fire, the Stgw. 57 was set on the ground and a weighted string attached near the muzzle was used as a plumb-line to set the correct firing angle reference mark on the bipod leg.
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The frontispiece depicts, at the top, the all-seeing Eye of Providence within a triangle representing the Holy Trinity. In each angle Hebrew letters spell out Jah, the name of God. Around this the nine orders of angels are arranged in three more overlapping triangles. Beneath this fly two putti, one carrying a ruler and a plumb line, while the other carries a tablet with the magic square of three.
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Geodetic coordinates At an arbitrary point consider the line which is normal to the reference ellipsoid. The geodetic coordinates are the latitude and longitude of the point on the ellipsoid and the distance . This height differs from the height above the geoid or a reference height such as that above mean sea level at a specified location. The direction of will also differ from the direction of a vertical plumb line.
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The torso sinks down as if following a plumb line and the sacrum curves forward and in or arches. Equal weighting (50-50) is given to each foot, making for a very stable stance. Ma Bu is frequently used for conditioning and building up knee strength. Many kung fu masters required students to be able to hold Ma Bu for at least five minutes before learning the forms of a style.
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After several mines that formed part of the net had been detonated to no avail,The type of net in use had electric contact mines that were triggered from the shore. See: Stern: p. 29. von Heimburg and his group rowed out and repeatedly dropped a plumb line until it contacted metal. Then, von Heimburg dropped a Turkish sinker mine with a shortened fuse right on top of E7.
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The deflection is the difference between the true zenith as determined by astrometry, and the apparent zenith as determined by a plumb-line Observatories were constructed to the north and south of the mountain, plus a bothy to accommodate equipment and the scientists. The ruins of these structures remain on the mountainside. Most of the workforce was housed in rough canvas tents. Maskelyne's astronomical measurements were the first to be conducted.
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Sixteen balls were dropped from a height of 241 feet, between June and September, 1791, and the plumb-line fixed in February, 1792, all during the night, to minimize the effects of road traffic. The mean deviations towards east and south proved to be 8.4 and 5.3 respectively, while the computation gave 7.6 and 6.2 (1= 1-12 inch).For metric equivalents, see: Ph. Gilbert. "Les preuves mécaniques de la rotation de la Terre".
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In this sense, a vertical wall allows more options. This is reflected in the tools a bricklayer uses: a plumb line for verticality and a spirit level to check that the mortar courses are horizontal. On the other hand, in contrast to a wall a horizontal floor allows more options when one considers compass directions. One can draw on a floor lines going north, south, east, and west, in fact, along any compass direction.
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A plumb bob A plumb bob, or plummet, is a weight, usually with a pointed tip on the bottom, suspended from a string and used as a vertical reference line, or plumb-line. It is a precursor to the spirit level and used to establish a vertical or horizontal datum. The instrument has been used since at least the time of ancient EgyptDenys A. Stocks. Experiments in Egyptian archaeology: stoneworking technology in ncient Egypt.
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For all practical purposes of the period, the changes as the meridian was moved went unnoticed. Transit instruments are installed to be perpendicular to the local level (which is a plane perpendicular to a plumb line). In 1884, the International Meridian Conference took place in Washington, D.C. to establish an internationally recognised single meridian. The meridian chosen was that which passed through the Airy transit circle at Greenwich, and it became the prime meridian of the world.
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The Plymouth Congregational Church is a historic church located at 3429 Devon Road corner of Main Highway in the Coconut Grove neighborhood of Miami, Florida, United States. The land was donated by George Spalding and George E. Merrick. The architect was Clinton MacKenzie. The Edifice Religious was founded in the 1897, and completed in the 1917, the church was built by a single man, Felix Rebom, using only a hatchet, a trowel, a plumb line, and a T-square.
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Navicula de Venetiis on display at Musée d'histoire des sciences de la Ville de Genève. A navicula de Venetiis or "little ship of Venice" was an altitude dial used to tell time and which was shaped like a little ship. The cursor (with a plumb line attached) was slid up/down the mast to the correct latitude. The user then sighted the Sun through the pair of sighting holes at either end of the "ship's deck".
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Read January 13, 1825. [Phil. Trans. 1825, p. 147.] His collimator was meant to replace a level, or plumb-line, in astronomical observations, and to furnish a ready and perfectly exact method of determining the position of the horizontal or zenith point on the limb of a circle or zenith sector. Its principle is the invariability, with respect to the horizon, of the position assumed by any body of invariable figure and weight floating on a fluid.
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Thus, inertial navigation is a form of dead reckoning that requires no external input, and therefore cannot be jammed by any external or internal signal source. A gyrocompass, employed for navigation of seagoing vessels, finds the geometric north. It does so, not by sensing the Earth's magnetic field, but by using inertial space as its reference. The outer casing of the gyrocompass device is held in such a way that it remains aligned with the local plumb line.
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In: Bulletin des sciences mathématiques et astronomiques, série 2, VI (1882), p. 189–223 In spite of their agreement both observation and calculation were defective, the plumb-line having been determined half a year later, and the theory of motion relative to the moving earth being as yet undeveloped. However, the tangential force that was applied to the body was known since Newton due to the rotation motion of the earth. Guglielmini therefore contributed to the understanding of the Earth's rotation.
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In the anterior/posterior view, deviation from vertical results in abnormal lateral curvature of the spine called scoliosis. In the sagittal view, excessive curvature in the cervical region is cervical lordosis, in the thoracic region thoracic kyphosis, and in the lumbar region lumbar lordosis. Reduction in curvature is typically termed flat back if present in the thoracic region and lumbar kyphosis if present in the lumbar region. In posture analysis, the spine is compared to a plumb line to detect the aforementioned abnormalities.
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After moving to the United States she gained her MFA in painting and printmaking from American University, the former in 1980 and the latter in 1983. Arbabi's 1984 work Plumb Line, in mixed media on paper, is owned by the Arthur M. Sackler Gallery of the Smithsonian Institution. A large collection of her art is held by the University of Maryland Art Gallery. Her 1996 mixed-media work Untitled #2 is owned by the United States Mission to the United Nations.
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In 1885, working as an assistant at the University of Karlsruhe, Rebeur-Paschwitz became interested in Friedrich Zöllner’s pendulum. In 1886, he started construction of a horizontal pendulum at the astronomical observatory of Karlsruhe with the idea to measure oscillations of the plumb line resulting from the influence of astronomical bodies. However, his pendulums appeared to be sensitive also to horizontal accelerations of the ground. Rebeur-Paschwitz became the first person to continuously record movements of the ground on photographic paper.
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The comparative measurement method requires proportional accuracy, but allows the artist to vary the size of the image created. This technique broadly encompasses any method of drawing that involves making accurate measurements primarily using the naked eye. In the early training period students may be aided by a pencil, brush or plumb line to make comparisons, but there is no transfer of 1:1 measurements from subject directly to paper. Schools that teach this method include The Water Street Atelier and The Swedish Academy of Realist Art.
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Finally, in 1854, Airy got the value by measurements in a coal mine in Harton, Sunderland. Airy's method assumed that the Earth had a spherical stratification. Later, in 1883, the experiments conducted by Robert von Sterneck (1839 to 1910) at different depths in mines of Saxony and Bohemia provided the average density values ρ between 5.0 and . This led to the concept of isostasy, which limits the ability to accurately measure ρ, by either the deviation from vertical of a plumb line or using pendulums.
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Such anecdotal details as these were embroideries upon the reputation of Daedalus as an innovator in many arts. In Pliny's Natural History (7.198) he is credited with inventing carpentry "and with it the saw, axe, plumb-line, drill, glue, and isinglass". Pausanias, in travelling around Greece, attributed to Daedalus numerous archaic wooden cult figures (see xoana) that impressed him: "All the works of this artist, though somewhat uncouth to look at, nevertheless have a touch of the divine in them."Pausanias, Description of Greece ii.4.5.
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Experiments were made mixing lime with other materials to provide a hydraulic mortar, but there was still no equivalent of the Roman concrete. In England, France and the Dutch Republic, cut and gauged brickwork was used to provide detailed and ornate facades. The triangulated roof truss was introduced to England and used by Inigo Jones and Christopher Wren. Many tools have been made obsolete by modern technology, but the line gauge, plumb-line, the carpenter's square, the spirit level, and the drafting compass are still in regular use.
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Astronomical latitude () is the angle between the equatorial plane and the true vertical direction at a point on the surface. The true vertical, the direction of a plumb line, is also the gravity direction (the resultant of the gravitational acceleration (mass-based) and the centrifugal acceleration) at that latitude. Astronomic latitude is calculated from angles measured between the zenith and stars whose declination is accurately known. In general the true vertical at a point on the surface does not exactly coincide with either the normal to the reference ellipsoid or the normal to the geoid.
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On his third voyage, Columbus formulated a new model of the Earth shortly after observing that the North Star is not fixed. Making observations with a quadrant, he "regularly saw the plumb line fall to the same point," instead of moving along as his ship moved. He divined that he had discovered the entrance to Heaven, from which Earth's waters extend, the planet forming a pear-shape with the insurmountable "stalk" portion of the pear pointing towards Heaven. In fact, the Earth ever so slightly is pear-shaped, with the "stalk" pointing North.
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Traditional geodetic instruments such as theodolites rely on the gravity field for orienting their vertical axis along the local plumb line or local vertical direction with the aid of a spirit level. After that, vertical angles (zenith angles or, alternatively, elevation angles) are obtained with respect to this local vertical, and horizontal angles in the plane of the local horizon, perpendicular to the vertical. Levelling instruments again are used to obtain geopotential differences between points on the Earth's surface. These can then be expressed as "height" differences by conversion to metric units.
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Chalk line tool. A chalk line or chalk box is a tool for marking long, straight lines on relatively flat surfaces, much farther than is practical by hand or with a straightedge. They may be used to lay out straight lines between two points, or vertical lines by using the weight of the line reel as a plumb line. It is an important tool in carpentry, the working of timber in a rough and unplaned state, as it does not require the timber to have a straight or squared edge formed onto it beforehand.
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The latter is particularly important because optical instruments containing gravity-reference leveling devices are commonly used to make geodetic measurements. When properly adjusted, the vertical axis of the instrument coincides with the direction of gravity and is, therefore, perpendicular to the geoid. The angle between the plumb line which is perpendicular to the geoid (sometimes called "the vertical") and the perpendicular to the ellipsoid (sometimes called "the ellipsoidal normal") is defined as the deflection of the vertical. It has two components: an east–west and a north–south component.
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It was necessary for him to determine the zenith distances with respect to the plumb line for a set of stars at the precise time that each passed due south (astronomic latitude). Weather conditions were frequently unfavourable due to mist and rain. However, from the south observatory, he was able to take 76 measurements on 34 stars in one direction, and then 93 observations on 39 stars in the other. From the north side, he then conducted a set of 68 observations on 32 stars and a set of 100 on 37 stars.
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This double numbering enables the instrument to measure either celestial altitude or zenith distance or both simultaneously. At the apex where the two graduated straight sides of the grid pattern meet in a right angle there is a pin hole with a cord in it and a small weight on the free end with a small bead that slides along the cord. The cord is called “Khait” and is used as a plumb line when measuring celestial altitudes. It is also used as the indicator of angles when doing calculations with the instrument.
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The difference between the direction of a plumb line or vertical, and a line perpendicular to the surface of the ellipsoid of revolution—a normal to said ellipsoid—at a particular observatory, is the deflection of the vertical. A GPS receiver at the marking strip of the prime meridian. The indicated longitude is not exactly zero because the geodetic zero meridian on a geocentric reference ellipsoid (which is what GPS positioning yields) is 102.478 metres east of this strip. When the Airy transit circle was built, a mercury basin was used to align the telescope to the perpendicular.
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In 1772 Maskelyne proposed to the Royal Society what was to become known as the Schiehallion experiment (named after the mountain on which it was performed), for the determination of the Earth's density using a plumb line. He was not the first to suggest this, Pierre Bouguer and Charles-Marie de la Condamine having attempted the same experiment in 1738. Maskelyne performed his experiment in 1774 on Schiehallion in Perthshire, Scotland,Philosophical Transactions of the Royal Society. 1. 495 the mountain being chosen due to its regular conical shape which permitted a reasonably accurate determination of its volume.
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Offset or "layback" can range from 0 mm to 45 mm. A seatpost with offset is necessary when the seat tube angle of the frame is too steep to give the desired saddle setback (the horizontal distance between a plumb line hung from the nose of the saddle and the bottom bracket spindle). Conversely, an "in line" post may be required if the seat tube angle is too slack. Some saddles, notably Brooks leather saddles, have relatively short rails, allowing less adjustment of setback, and changing the seatpost or inserting a saddle adjuster may be the only way to achieve the correct position.
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All of these Greenwich meridians were located via an astronomic observation from the surface of the Earth, oriented via a plumb line along the direction of gravity at the surface. This astronomic Greenwich meridian was disseminated around the world, first via the lunar distance method, then by chronometers carried on ships, then via telegraph lines carried by submarine communications cables, then via radio time signals. One remote longitude ultimately based on the Greenwich meridian using these methods was that of the North American Datum 1927 or NAD27, an ellipsoid whose surface best matches mean sea level under the United States.
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The sound and visuals grow more intense as the film progresses, with Schneemann narrating about a period of physical and emotional illness. The film ends with Schneemann attacking a series of projected images and a repetition of the opening segment of the film. During a showing of Plumb Line at a women's film festival, the film was booed for the image of the man at the beginning of the film. From 1973 to 1976, in her ongoing piece Up to and Including Her Limits, a naked Schneemann is suspended from a tree surgeon's harness, which is attached from the ceiling above a canvas.
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The exact design of the merkhet consists of a horizontal bar, usually carved from wood or bone, with a plumb line hanging from a transverse hole at one raised end of the bar, attached to a controlling wooden handle. As deduced by texts and engravings on the inner walls of the temples of Dendera and Edfu, the merkhet was typically used in conjunction with a corresponding sighting tool, which the Egyptians called a bay, itself made from a specially cut palm- rib with a sliced "V" shape at one end. The two together could also be used, as appropriate, to determine North.Stocks, p.
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They sailed further west, where the sight of pearls compelled Columbus to send men to obtain some, if not gold. The natives provided nourishment including a maize wine, new to Columbus. Compelled to reach Hispaniola before the food aboard his ship spoiled, Columbus was disappointed to discover that they had sailed into a gulf, and while they had obtained fresh water, they had to go back east to reach open waters again. At sea, Columbus observed that the North Star is not fixed, then, making observations with a quadrant, "regularly saw the plumb line fall to the same point," instead of moving respectively to his ship.
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Sketch of John Henry Pratt in 1839 John Henry Pratt FRS (4 June 1809 – 28 December 1871) was a British clergyman, astronomer and mathematician. A Cambridge Apostle, he joined the British East India Company in 1838 as a chaplain and later became Archdeacon of Calcutta. Although nominated as Bishop of Calcutta, the decision was rescinded at the last moment with George Cotton being appointed to the position. A gifted mathematician who worked on problems of geodesy and earth science, he was approached by the Surveyor General of India to examine the errors in surveys resulting from the attraction of the plumb-line to the mass of the Himalayan mountains.
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These early empirical investigations used the criterion of singleness of vision, or absence of diplopia to determine the horopter. Today the horopter is usually defined by the criterion of identical visual directions (similar in principle to the apparent motion horopter, according that identical visual directions cause no apparent motion). Other criteria used over the years include the apparent fronto-parallel plane horopter, the equi- distance horopter, the drop-test horopter or the plumb-line horopter. Although these various horopters are measured using different techniques and have different theoretical motivations, the shape of the horopter remains identical regardless of the criterion used for its determination.
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Plumb line method The experimental determination of the center of mass of a body uses gravity forces on the body and relies on the fact that in the parallel gravity field near the surface of the earth the center of mass is the same as the center of gravity. The center of mass of a body with an axis of symmetry and constant density must lie on this axis. Thus, the center of mass of a circular cylinder of constant density has its center of mass on the axis of the cylinder. In the same way, the center of mass of a spherically symmetric body of constant density is at the center of the sphere.
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From around 2500BCE, as Thuban became less and less aligned with the celestial north, Kochab became one pillar of the circumpolar stars, first with Mizar, a star in the middle of the handle of the Big Dipper (Ursa Major), and later with Pherkad (in Ursa Minor). In fact, around the year 2467BCE, the true north was best observed by drawing a plumb line between Mizar and Kochab, a fact with which the Ancient Egyptians were well acquainted as they aligned the great Pyramid of Giza with it. This cycle of the succession of pole stars occurs due to the precession of the equinoxes. Kochab and Mizar were referred to by Ancient Egyptian astronomers as 'The Indestructibles' lighting the North.
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The evidence they afforded of his capacity, and the fact that he already had received a scientific appointment, probably led to his being selected in the same year to make some geological and mineralogical investigations in Scotland. He was in 1809 to identify limestone suitable for use in gunpowder making. He was also consulted on the suitability of the chief Scottish mountains for a repetition of the pendulum experiments previously conducted by Nevil Maskelyne and John Playfair at Schiehallion, and on the deviations of the plumb-line along the meridian of the Trigonometrical Survey. In the course of the explorations necessary for the purposes of these reports he made extensive observations on the geology and mineralogy of Scotland.
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A pendulum hangs straight downwards in a symmetrical gravitational field. However, if a sufficiently large mass such as a mountain is nearby, its gravitational attraction should pull the pendulum's plumb-bob slightly out of true (in the sense that it doesn't point to the centre of mass of the Earth). The change in plumb-line angle against a known object—such as a star—could be carefully measured on opposite sides of the mountain. If the mass of the mountain could be independently established from a determination of its volume and an estimate of the mean density of its rocks, then these values could be extrapolated to provide the mean density of the Earth, and by extension, its mass.
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Bey also wrote: "The Mackay Society, of which Mark & I are active members, is devoted to the anarchism of Max Stirner, Benj. Tucker & John Henry Mackay...The Mackay Society, incidentally, represents a little-known current of individualist thought which never cut its ties with revolutionary labor. Dyer Lum, Ezra & Angela Haywood represent this school of thought; Jo Labadie, who wrote for Tucker's Liberty, made himself a link between the american “plumb-line” anarchists, the "philosophical" individualists, & the syndicalist or communist branch of the movement; his influence reached the Mackay Society through his son, Laurance. Like the Italian Stirnerites (who influenced us through our late friend Enrico Arrigoni) we support all anti-authoritarian currents, despite their apparent contradictions".
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Thus the circle was aligned with the local vertical or plumb line, which is deflected slightly from the normal, or line perpendicular, to the reference ellipsoid used to define geodetic latitude and longitude in the International Terrestrial Reference Frame (which is nearly the same as the WGS-84 system used by GPS). While the local vertical defined at the Airy transit circle still points to the modern celestial meridian (the intersection of the prime meridian plane with the celestial sphere), it does not pass through the Earth's rotation axis. As a result of this, the ITRF zero meridian, defined by a plane passing through the Earth's rotation axis, is 102.478 metres to the east of the prime meridian. A 2015 analysis by Malys et al.
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Cunningham, as with Dickinson and Dickinson's teacher, Charles Hawthorne, is part of an unconventional approach to realism and representation in American painting that began in 1914. They share a way of looking and painting summarized in the term "color-spots" that Hawthorne invented, Dickinson practiced and taught, and that Cunningham developed and passed on as a technique. Cunningham began teaching at the City College of New York (1962-1965) and the Brooklyn Museum Art School (1962-1980). His Sunday high school scholarship class at BMAS came to be known for its nontraditional methods of figurative painting, observing directly from nature using a plumb- line and finder, and putting down on the flat surface of the canvas abstracted color-value notes.
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A simple scale hypsometer allows the height of a building or tree to be measured by sighting across a ruler to the base and top of the object being measured, when the distance from the object to the observer is known. Modern hypsometers use a combination of laser rangefinder and clinometer to measure distances to the top and bottom of objects, and the angle between the lines from the observer to each to calculate height. 300pxAn example of such a scale hypsometer is illustrated here, and can be seen to consist of a sighting tube, a fixed horizontal scale, and an adjustable vertical scale with attached plumb line. The principle of operation of such a scale hypsometer is based on the idea of similar triangles in geometry.
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At the age of 35, Knorre, who always had a strong interest in science and mathematics, began to explore astronomy. At that time, the city of Dorpat had no university, and Knorre had little support in his scholastic pursuits, but he nevertheless undertook a daily record of his work, making regular entries about his celestial observations in his journal as early as 1795. That same year, he began to design and construct his own astronomical instrument, and set out to determine the geographical latitude of the city of Dorpat. With the help of little more than a plumb-line and bob, he fixed four plates with a series of round holes atop the wall of the two-story home where he lived.
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Because of the Coriolis effect, falling bodies veer slightly eastward from the vertical plumb line below their point of release, and projectiles veer right in the Northern Hemisphere (and left in the Southern) from the direction in which they are shot. The Coriolis effect is mainly observable at a meteorological scale, where it is responsible for the opposite directions of cyclone rotation in the Northern and Southern hemispheres (anticlockwise and clockwise, respectively). Hooke, following a suggestion from Newton in 1679, tried unsuccessfully to verify the predicted eastward deviation of a body dropped from a height of , but definitive results were obtained later, in the late 18th and early 19th century, by Giovanni Battista Guglielmini in Bologna, Johann Friedrich Benzenberg in Hamburg and Ferdinand Reich in Freiberg, using taller towers and carefully released weights.See Fallexperimente zum Nachweis der Erdrotation (German Wikipedia article).
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Gunter's quadrant is an instrument made of wood, brass or other substance, containing a kind of stereographic projection of the sphere on the plane of the equinoctial, the eye being supposed to be placed in one of the poles, so that the tropic, ecliptic, and horizon form the arcs of circles, but the hour circles are other curves, drawn by means of several altitudes of the sun for some particular latitude every year. This instrument is used to find the hour of the day, the sun's azimuth, etc., and other common problems of the sphere or globe, and also to take the altitude of an object in degrees. A rare Gunter quadrant, made by Henry Sutton and dated 1657, can be described as follows: It is a conveniently sized and high-performance instrument that has two pin-hole sights, and the plumb line is inserted at the vertex.
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Such a model had first been theorized by Christopher Columbus on his third voyage. Making observations with a quadrant, he "regularly saw the plumb line fall to the same point," instead of moving respectively to his ship, and subsequently hypothesized that the planet is pear-shaped. John A. O'Keefe and co-authors are credited with the discovery that the Earth had a significant third degree zonal spherical harmonic in its gravitational field using Vanguard 1 satellite data.O’KEEFE, J. A., ECKEIS, A., & SQUIRES, R. K. (1959). Vanguard Measurements Give Pear-Shaped Component of Earth’s Figure. Science, 129(3348), 565–566. doi:10.1126/science.129.3348.565 Based on further satellite geodesy data, Desmond King-Hele refined the estimate to a 45-m difference between north and south polar radii, owing to a 19-m "stem" rising in the north pole and a 26-m depression in the south pole.King-Hele, D. (1967).
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The ceiling of the Blue Velvet Room depicting "Architecture" The Blue Velvet Room is a perfect cube measuring square to the egg-and-dart lip. This room was Lord Burlington's studiola or ‘Drawing Room’ and originally contained a large table by William Kent which contained many designs by architects such as Andrea Palladio, Inigo Jones, John Webb and Vincenzo Scamozzi, which were ready for inspection. The ceiling is supported by eight large cyma reversa brackets, all in the Italian manner. Snakes and rats, symbols sacred to Venus and Apollo, in the ceiling The coved ceiling, painted by William Kent, depicts a personification of ‘Architecture’ accompanied by three putti who grasp architectural implements in the form of T-Square, Set-Square and plumb line. ‘Architecture’ herself holds dividers and an unknown Temple plan (possible derived from the Jesuit architect Juan Bautista Villalpando who produced a classical reconstruction of the sanctum sanctorum at the heart of Solomon's Temple).
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It being typical to orientate the instrument such that the operator faces looking slightly down upon the scale, the Sun at the users left, with right hand placed in such a way that the rays of sunlight pass through the two, perforated sighting plates, forming a bright illuminated spot on the observer's finger (see photo), the finger functioning as a projection screen. At the moment an optical alignment with the Sun is established, the angular value of the device is read by the operator at the point where the graduated scale is bisected by the hanging plumb line. These instruments, with poor angular resolution, not principally intended to function with stars at night, as an astronomical measuring device, since it is impractical to sight a star through the front pin hole (aperture) less on a fixed, stabilized mount relative to the half degree width of the very intense Sun. The maritime (navigation) version of these devices being skeletal in design rather than solid sheet form, so as to limit buffeting or displacement of the instrument while in the operators hand from wind exposure.
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