Envisioned by Chinese-American artists Cheryll Leo-Gwin and Stewart Wong, the design depicts a giant plumb bob balanced on its tip, to stand outside a district courthouse.
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In addition to the plumb bob, the artists also envision inscribing dates into the ground to form a circle, each one marking landmark civil rights achievements from 1882 onwards.
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While most of the competitors opted for a craft that went "lawnmower-style" above the sea floor at a given depth, Tao's craft dropped down like a plumb bob, pinging the depths as it went down and back up before moving to a new spot.
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It is a vector (physics) quantity, and its direction coincides with a plumb bob.
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Swiss army knives were often used as a makeshift plumb bob at the end of the string.
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Plumb bob with scale as an inclinometer A plumb bob and line alone can determine only a vertical reference. However, if they are mounted on a suitable scale the instrument may also be used as an inclinometer to measure angles to the vertical. The early skyscrapers used heavy plumb bobs, hung on wire in their elevator shafts. A plumb bob may be in a container of water (when conditions are above freezing temperatures), molasses, very viscous oils or other liquids to dampen any swinging movement,Staley, W. W.. Introduction to mine surveying,.
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After a Mediterranean deployment in early 1966, the ship took part in "Plumb Bob II" and provided services for the David Taylor Model Basin.
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About six or seven inches from the end of the angle-bar is a little hole (D) about as big as a shoelace or thick cord. At the other end, where it is inserted into the ruler, is another hole (B) at the central vertical line. :The second part of this instrument is a pendulum, that is, a plumb-bob (E) approximately one inch in diameter, pierced through with a hole the size of a thick cord, and through this hole is passed the cord, knotted above the plumb-bob. :The cord and its plumb-bob are attached to the ruler by passing the cord through holes D and B in the angle-bar, so that one of the ends of the rope coincides with the central division line, and the other end, with the plumb-bob, hangs [pend] in the air, which is why it is called a pendulum.
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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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Along one edge there were two sights forming an alidade. A plumb bob was suspended by a line from the centre of the arc at the top. In order to measure the altitude of a star, the observer would view the star through the sights and hold the quadrant so that the plane of the instrument was vertical. The plumb bob was allowed to hang vertical and the line indicated the reading on the arc's graduations.
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Double pentaprism as used in surveying. In surveying a double pentaprism (two pentaprisms stacked on top of each other) and a plumb-bob are used to stake out right angles, e.g. on a construction site.
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Note, frame dragging will neither accelerate nor slow down the bowling ball in either direction. It is not a "viscosity". Similarly, a stationary plumb-bob suspended over the rotating object will not list. It will hang vertically.
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Double pentaprism as used in surveying. In surveying it is used both as a hand held tool for sighting between two poles (often with a plumb bob hung from the handle) and also mounted on a Jacob's staff.
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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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On a smaller scale, a mountain to one side may deflect the plumb bob away from the true zenith.Such a deflection was measured by Nevil Maskelyne. See Maskelyne, N. (1775). "An Account of Observations Made on the Mountain Schiehallion for Finding Its Attraction". Phil. Trans.
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Double prism as used in surveying. A double prism is a device to measure right angles, consisting of two five sided prisms stacked on top of each other and a plumb-bob. It is used to stake out right angles, for example on a construction site.
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Polaris currently traces a circle 0.73° in radius around the north celestial pole, so this technique is accurate to within a degree. At high latitudes a plumb-bob is helpful to sight Polaris against a reference object close to the horizon, from which its bearing can be taken.
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Geometric quadrant with plumb bob. The geometric quadrant is a quarter-circle panel usually of wood or brass. Markings on the surface might be printed on paper and pasted to the wood or painted directly on the surface. Brass instruments had their markings scribed directly into the brass.
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Brick wall showing horizontal mortar courses and vertical perpendiculars. By contrast, a level floor only contains horizontal lines. On a (horizontal) floor, one can draw a horizontal line but not a vertical line in the sense of a plumb bob line. But on a (vertical) wall, one can draw both vertical and horizontal lines.
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Plumb bob lines descended from the scales above and intersected with linear scales marked on the horizontal scales below. These allowed measures to be read, not as angles, but as trigonometric ratios. To celebrate the 600th anniversary of the Rectangulus in 1926 a replica was constructed. This is now in the Museum of the History of Science, Oxford.
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Many modern tripods are constructed of aluminum, though wood is still used for legs. The feet are either aluminum tipped with a steel point or steel. The mounting screw is often brass or brass and plastic. The mounting screw is hollow and has two lateral holes to attach a plumb bob to center the instrument e.g.
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In addition to the calculating machine, in his career Grillet invented a hygrometer (for which he was accused of plagiarism by another inventor); graphometers; drawing instrument set; protractor, set square, with plumb-bob. In 1690, the first textile-printing factory in England was established by a Frenchman named René Grillet, who took out a patent on the process.
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A hematite mason's plummet 240 is a mason's plummet. A plummet amulet is an amulet created by Ancient Egyptians in the shape of a plumb bob or plummet. They included these plummet amulets in the mummification process because they believed it would bring balance to the deceased in their next life., as quoted in ; no access to original source.
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The three rings are oriented with respect to the local meridian, the planet's equator, and a celestial object. The instrument itself can be used as a plumb bob to align it with the vertical. The instrument is then rotated until a single light beam passes through two points on the instrument. This fixes the orientation of the instrument in all three axes.
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It is thought that a vertical alignment between these two stars checked with a plumb bob was used to ascertain where North lay. The deviations from true North using this model reflect the accepted dates of construction of the pyramids. Egyptians were the first to develop a 365-day, 12 month calendar. It was a stellar calendar, created by observing the stars.
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So another solution was required. Thousands of years ago, many cultures used the plumb bob to find proper alignment and it was decided to use this technique to obtain perfect alignment. Two readings were taken separated by two hours to obtain a very accurate triangulated result. Exact positions of the sun for the Observatory location were taken from a smartphone using an astronomy application.
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432d Fighter-Interceptor Squadron Northrop F-89H ScorpionAircraft is Northrop F-89H-5-NO Scorpion serial 54-409, stationed at Minneapolis-Saint Paul International Airport, Minnesota. Taken at Indian Springs Air Force Auxiliary Field, Nevada, armed with a "Genie" nuclear missile. Aircraft fired the nuclear weapon as the "John Shot" of Operation Plumb Bob, 19 July 1959 Air Defense of Upper Midwest, 1952–1958.
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It was not uncommon for a second person to take the reading while the first concentrated on observing and holding the instrument in proper position. The accuracy of the instrument was limited by its size and by the effect the wind or observer's motion would have on the plumb bob. For navigators on the deck of a moving ship, these limitations could be difficult to overcome.
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Among the most significant items is the earliest known Imperial face-mask. Other items include locks, keys, razors, a scale, weights, chisels, hammers, pickaxes, buckets, finger rings, surgical instruments, seal boxes, a stylus, cauldrons, casseroles, spoons, and amphorae. Jewelry, hairpins, and a disk brooch suggest the presence of women. One of the inscribed objects is a plumb bob with "CHOI", or "C(o)HO(rtis) I", i.e.
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This was superseded by the Richards Box in which an adjustable brass Kendrew molecular model was placed front of a 2-way mirror, behind which were plastic sheets of the electron density map. This optically superimposed the molecular model and the electron density map. The model was moved to within the contour lines of the superimposed map. Then, atomic coordinates were recorded using a plumb bob and a meter stick.
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The installation of many dials requires knowing the local latitude, the precise vertical direction (e.g., by a level or plumb- bob), and the direction to true North. Portable dials are self-aligning: for example, it may have two dials that operate on different principles, such as a horizontal and analemmatic dial, mounted together on one plate. In these designs, their times agree only when the plate is aligned properly.
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Bracing wires must be carefully rigged to maintain the correct length and tension. In flight the wires tend to stretch under load and on landing some may become slack. Regular rigging checks are required and any necessary adjustments made before every flight. Rigging adjustments may also be used to set and maintain wing dihedral and angle of incidence, usually with the help of a clinometer and plumb-bob.
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The builder's rating badge shows two traditional tools for construction - the carpenter's square and the plumb-bob. At the senior chief petty officer level, the builder rating merges with the engineering aide and steelworker ratings. At this level, they are referred to as a senior chief constructionman (abbreviated as CUCS). At the master chief petty officer level, they are referred to as a master chief constructionman (abbreviated as CUCM).
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See for example Charles Hutton's 1815 list of England's most notable private observatories included Colonel Beaufoy's. In 1816 Beaufoy published another extensive article based on his experimental work. On the Stability of Vessels was based on 23 different hull forms tested for their resistance to rolling. The article includes an illustration of his apparatus showing a hull form being subjected to a controlled heeling force with a plumb bob and scale to measure the inclination.
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After speeches had been made, the freemasons presented the king with "the working tools of a mason", a plumb bob, level, square tool, and a trowel. In between the laying of the cornerstone and the finishing of the new palace, Kalākaua had seen how other monarchs lived. He wanted ʻIolani to measure up to the standards of the rest of the world. The furnishing and interiors of the finished palace were reflective of that.
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Schiehallion force diagram Consider the force diagram to the right, in which the deflection has been greatly exaggerated. The analysis has been simplified by considering the attraction on only one side of the mountain. A plumb-bob of mass is situated a distance from , the centre of mass of a mountain of mass and density . It is deflected through a small angle due to its attraction towards and its weight directed towards the Earth.
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Trumpetfish resumed a schedule of local antisubmarine warfare operations out of Charleston, alternating deployments to the Mediterranean and duty with the Sixth Fleet. She participated in emergency operations during the tension precipitated by the Cuban Missile Crisis in October 1962. The submarine later participated in several inter-type fleet exercises in home waters and in the Caribbean. Trumpetfish underwent a routine yard period at Charleston before taking part in Exercises "Plumb Bob I" and "Minibox" in 1965.
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It is set into motion at the height of a quarter of a quarter of a circle, which is done by moving the plumb-bob two feet from perpendicular, or from its resting position, when the peg is in hole 72, or one foot when the peg is in hole 36, and six inches when the peg is in hole 18, and always a bit less as the pendulum becomes shorter. If one lets go of the plumb-bob without forcing it, the pendulum can mark with utmost precision the quickness or the slowness of the musical beat, as a result of the swings [vibrations] at its various lengths. :If a composer wants to mark the desired tempo for performing an air he has composed, irrespective of the time signature he must begin by putting the peg in one of the holes and then setting the pendulum in motion. If the swings are too slow, he must shorten the pendulum by putting the peg in a lower number.
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They dug with pickaxes and a gad, using gunpowder to loosen the harder rock of the lower layers. Shaunce used a plumb-bob to ensure that he was keeping the shaft perfectly straight, and a windlass to haul out the broken rock. Shaunce calculated where to begin digging the horizontal tunnel by standing across the water and sighting with his rifle directly below the top of the shaft. He dug in from the riverbank, using a line of stakes to maintain his alignment.
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In June, the ship successfully passed a nuclear technical proficiency inspection; acted as a setting for a training film; and transported a Marine Corps engineering company to Vieques Island and back. From 5 to 21 July, York County participated in the anti- submarine Exercise "Plumb Bob III." During August, York County supported LVT training for Marine Corps reservists and provided control ship duty for drones. She spent September and October in restricted availability and on standby duty, ready to support NASA operations.
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Consider a point on the Earth under the joint action of the annual and diurnal movements. At one time these are added together and 12 hours later they act against each other, so there is an alternate speeding up and slowing down. So the ocean basins are affected in the same way as the barge particularly in an east-west direction. The length of the barge makes a difference to the speed of oscillations, just as the length of a plumb bob changes its speed.
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Strictly, vertical walls are never parallel on the surface of a spherical planet When the curvature of the earth is taken into account, the concepts of vertical and horizontal take on yet another meaning. On the surface of a smoothly spherical, homogenous, non-rotating planet, the plumb bob picks out as vertical the radial direction. Strictly speaking, it is now no longer possible for vertical walls to be parallel: all verticals intersect. This fact has real practical applications in construction and civil engineering, e.g.
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Homer is leaving the Power Plant for the weekend, as he promised Marge to be home for dinner. However, as he is leaving, Mr. Burns asks him for his help to fix a gas leak with a "Safety First" poster, and to measure its level with a plumb bob (a procedure that takes hours to complete). At home, Marge is having trouble taking care of the kids. She is trying to help Lisa with a school project (dressing her as a male seahorse) and feed Maggie.
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They were constructed with a hinged gnomon, whose angle could be adjusted for the latitude; the latitude was indicated by the beak of a bird. The gnomon was held in place by a rivet which was displayed by the birds eye, and thumbscrew. The dial plate would have three chapter rings for 44°, 48° and 52° which would be sufficiently accurate to be used between 35° and 60° (roughly between Gibraltar to the Shetland Isles). There would also be a compass and a plumb bob.
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The last name Páez Vilaró is recognized worldwide for the work of her father Carlos, and because her brother Carlos is a survivor of the 1972 Andes flight disaster. She is the granddaughter of an Argentine woman from Rosario. She has taken the Camino de Santiago road several times, as well as the Inca Trail, and has hiked to the Interior of Uruguay on foot. Together with her two brothers, she helped her father to build Casapueblo, which would be his home, with wavy lines, without straightedge, plumb bob, or level.
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The serpent is a chthonic god of knowledge and of immortality, because he sloughs off his skin. The serpent guards the Tree in the Greek Garden of the Hesperides and, later, a Tree in the Garden of Eden. The serpent in the skull is always making its way through the socket that was the eye: knowledge persists beyond death, the emblem says, and the serpent has the secret. Symbolism of chance (Fortuna's wheel) divine justice (right angle and plumb-bob) and mortality in a Pompeiian mosaic The skull speaks.
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Point Zero Bridge, decorated with a plumb-bob, symbolizes the center of the city. Medellín in 2013 won the Veronica Rudge Green Prize in Urban Design, awarded by Harvard University, due to PUI Integral Urban Project Northeast area, designed and implemented by Development Corporation Urbano. Medellín retains very little colonial architecture from the nineteenth century. Although the Aburrá Valley was a hotspot in agriculture and livestock throughout the colonial period, their relative wealth is not expressed in an outstanding and Cartagena, Tunja, Popayán and Bogotá civil and religious architecture.
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Maskelyne then proposed measuring the gravitational force causing this deflection induced by the pull of a nearby mountain upon a plumb-bob in 1772 and sent Mason (who had returned to Britain) on a site survey through central England and Scotland to find a suitable location during the summer of 1773. Mason selected Schiehallion at which to conduct what became known as the Schiehallion experiment, which was carried out primarily by Maskelyne and determined the density of the Scottish mountain. Several years later Cavendish used a very sensitive torsion balance to carry out the Cavendish experiment and determine the average density of Earth.
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Horrocks was the first to demonstrate that the Moon moved in an elliptical path around the Earth, and he posited that comets followed elliptical orbits. He supported his theories by analogy to the motions of a conical pendulum, noting that after a plumb bob was drawn back and released it followed an elliptical path, and that its major axis rotated in the direction of revolution as did the apsides of the Moon's orbit. He anticipated Isaac Newton in suggesting the influence of the Sun as well as the Earth on the Moon's orbit. In the PrincipiaIsaac Newton, 'Principia', Book 3, Proposition 35, Scholium.
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The pyramids of Giza Since the first modern measurements of the precise cardinal orientations of the pyramids by Flinders Petrie, various astronomical methods have been proposed for the original establishment of these orientations.Belmonte 2001Neugebauer 1980Magli 2013 It was recently proposed that this was done by observing the positions of two stars in the Plough / Big Dipper which was known to Egyptians as the thigh. It is thought that a vertical alignment between these two stars checked with a plumb bob was used to ascertain where north lay. The deviations from true north using this model reflect the accepted dates of construction.
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The tool that was used to measure the level of the water course, and so to carry the water a long distance with a minimal drop, was a wooden bow and plumb bob. Taking the water at this higher level to the area of diggings and sluicing, allowed the workers then to process much more pay-dirt than the more typical method of digging it out and carrying it to the water. The place possesses uncommon, rare or endangered aspects of the cultural or natural history of New South Wales. Wall constructions of this scale (height & length) are rare.
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This site shows significant evidence of Chinese presence in Australia, especially as this wall appears to be wholly attributed to the Chinese. The wall which was built to support a water race for alluvial gold mining in the valley of the Meroo River, is exceptional in its scale, being higher than most similar constructions having been built in very difficult terrain. It was built with only primitive implements, using a wooden bow and plumb bob to accurately provide minimum fails to the water course over a long distance. The wall is in excellent condition, a testimony to the considerable masonry skills of the Chinese builders.
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In Lower Egypt, priests built circular mud-brick walls with which to make a false horizon where they could mark the position of the sun as it rose at dawn, and then with a plumb-bob note the northern or southern turning points (solstices). This allowed them to discover that the sun disc, personified as Ra, took 365 days to travel from his birthplace at the winter solstice and back to it. Meanwhile, in Upper Egypt a lunar calendar was being developed based on the behavior of the moon and the reappearance of Sirius in its heliacal rising after its annual absence of about 70 days.Tyldesley, Joyce, Pyramids: The Real Story Behind Egypt's Ancient Monuments, Viking, 2003, p.
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In 1880 Edinburgh, Scotland, Professor Sir Oliver Lindenbrook (James Mason), a geologist at the University of Edinburgh, is given a piece of volcanic rock by his admiring student, Alec McEwan (Pat Boone). Finding the rock unusually heavy, Lindenbrook, mostly due to carelessness by his lab assistant, Mr. Paisley (Ben Wright), discovers a plumb bob inside bearing a cryptic inscription. Lindenbrook and Alec discover that it was left by a scientist named Arne Saknussemm, who had, almost 300 years earlier, found a passage to the center of the Earth by descending into Snæfellsjökull, a volcano in western Iceland. After translating the message, Lindenbrook immediately sets off with Alec to follow in the Icelandic pioneer's footsteps.
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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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It was often marked by a "station disk" (see upper photo at left), a brass disk with a triangle inscribed on its surface and an impressed mark that indicated the precise point over which a surveyor's plumb-bob should be dropped to assure a precise location over it. A triangulation station was often surrounded by several (usually three) reference marks (see second photo at left),These marks were often set at roughly equal (120-degree) intervals from each other and were numbered in ascending order moving clockwise around the main station. each of which bore an arrow that pointed back towards the main station. These reference marks made it easier for later visitors to "recover" (or re-find) the primary ("station") mark.
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Thomas Rowlandson: Naval carpenter, 1799 The bush carpenter historically possessed few tools, and rarely any specialized tools. Mann's Emigrant's Guide of 1849 suggests that those heading for Australia's unsettled areas take with them a plentiful supply of a wide variety of tools and fasteners, but he lists as the very minimum, 'A hand saw; Axe; Adze; Mortising chisel; Two augers, 1 and 11/4 inch; Two maul rings;Iron collars that prevent damage to a maul's handle Set of wedges; 1 Spade; Pick-axe; Two-foot rule; Chalk line; Square; A Plumb Bob.'Mann, cited in Cox, Rude Timber Buildings p. 42 A majority of early settlers had formerly been manual labourers, or servicemen, and brought with them a sound practical ability and aptitude for 'making do'; others observed or helped and copied their techniques.
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Parts of the 49th parallel were originally surveyed using astronomical techniques that did not take into account slight departures of the Earth's shape from a simple ellipsoid, or the deflection of the plumb-bob by differences in terrestrial mass. The surveys were subject to the limitations of early to mid-19th century technology, but accurate results were obtained. However, in some places the surveyed 49th parallel is several hundred feet from the geographical 49th parallel for the currently adopted datum, the North American Datum of 1983 (NAD 83). The Digital Chart of the World (DCW), which uses the Clarke 1866 ellipsoid, reports the border on average at latitude 48° 59′ 51″ north, roughly south of the modern 49th parallel. It ranges between 48° 59′ 25″ and 49° 0′ 10″ north, and on either side of the average.
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The design of a simple Mariner's Quadrant Another latitude-divining instrument was the quadrant. Although their functions were the same, they were developed independently for separate use; the kamal was nautical while the quadrant was astronomical. The idea was born with Ptolemy in the 1st century, and was once again pioneered by the Arabs; its intended purpose was to solve trigonometric functions dictating celestial movement. However, the dual sighting mechanism of the period was too complicated, time consuming, and required too many men for practical use aboard a ship, as a result Iberian captains stripped it down to its most basic parts in order for it to be applied to navigation.ThinkQuest: Library, “Early Navigational Instruments ” The apparatus itself was either a wood or brass quarter circle with degree measurements painted along its length and a length of string attached to the point to serve as a plumb bob.
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It could also be argued that Niccolò Tartaglia's invention of the gunner's quadrant (see clinometer) in the 16th century introduced indirect fire guns because it enabled gunlaying by instrument instead of line of sight.Artillery: Its Origin, Heyday and Decline, Brigadier O. F. G. Hogg, 1970, C. Hurst and Company This instrument was basically a carpenter's set square with a graduated arc and plumb-bob placed in the muzzle to measure an elevation. There are suggestions,The History of the Royal Artillery from the Indian Mutiny to the Great War, Vol II, 1899–1914, Major General Sir John Headlam, 1934 based on an account in Livre de Canonerie published in 1561 and reproduced in Revue d'Artillerie of March 1908, that indirect fire was used by the Burgundians in the 16th Century. The Russians seem to have used something similar at Paltzig in 1759 where they fired over trees, and their instructions of the time indicate this was a normal practice.
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It says "Et in Arcadia ego" or simply "Vanitas." In a first-century mosaic tabletop from a Pompeiian triclinium (now in Naples), the skull is crowned with a carpenter's square and plumb-bob, which dangles before its empty eyesockets (Death as the great leveller), while below is an image of the ephemeral and changeable nature of life: a butterfly atop a wheel--a table for a philosopher's symposium. Calavera de la Catrina by José Guadalupe Posada (1851-1913) An example of the OSS "Black Propaganda" Humor: at left an Adolf Hitler profile on a "German Reich" stamp; at right the OSS-forged Hitler face version, turned into a death's head on a "Fallen Reich" stamp Similarly, a skull might be seen crowned by a chaplet of dried roses, a carpe diem, though rarely as bedecked as Mexican printmaker José Guadalupe Posada's Catrina. In Mesoamerican architecture, stacks of skulls (real or sculpted) represented the result of human sacrifices.
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