The hachures are traditionally monocolour, usually black, gray or brown. Using two complementary colours for the hachures on a neutral background colour (e.g. black and white lines on gray map colour) would give a shading effect as if the relief were illuminated.
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In representing relief with hachures on a map, six rules are to be followed, according to G.R.P. Lawrence (1979): # The hachures are drawn in the direction of the steepest gradient. # The hachures are arranged in rows perpendicular to their direction. # The length and thickness of each stroke represents the drop in height along its direction: a short and thick stroke represents a short and steep slope, while a long and thin stroke represents a long and gentle slope. # The strokes are spaced at an equal distance inside a row.
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Land case 236 SD, page 29; land case map A-1272 (Bancroft Library).Shows drainage, boundaries, adjoining ranchos, etc.Relief shown pictorially and by hachures. Creator/Contributor: United States.
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Hachure representation of relief was standardized by the Austrian topographer Johann Georg Lehmann in 1799. Hachures may be combined with other ways of representing relief, such as shades, the result being a shaded hachure map; an example of such a map is the Dufour Map of Switzerland.Dufour Map from The Federal Office of Topography of Switzerland uc as Emil von Sydow designed maps with coloured hachures: green for lowlands and brown for highlands.
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Confederate position map of the First Battle of Manassas from the American Civil War. Includes some troop positions and lists of Confederate regiments with the names of their commanders. Relief shown by hachures. Scale [1:63,360].
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In typical Renaissance production style, this tapestry would have been woven using a warp stretched over two rollers, following a painted cartoon underneath it using small areas of color, or hachures, that in juxtaposition form complicated visual effects of vibration and shading.
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The countryside (which in Switzerland is mostly hilly or mountainous) is depicted on the Dufour Map with hachures, which makes it appear especially vivid. Relief and elevation differences under the surface of lakes were symbolized by contours. This so-called "Swiss style" depiction received much praise, and earned the Topographic Bureau several international awards.
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Cortes' invasion route of Mexico. Hachures are strokes (short line segments or curves) drawn in the direction of the steepest slope (the aspect direction). Steeper slopes are represented by thicker, shorter strokes, while gentler slopes are represented by thinner, longer and farther apart strokes. A very gentle slope or a flat area, like the top of a hill, is usually left blank.
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Hachures () are an older mode of representing relief. They show orientation of slope, and by their thickness and overall density they provide a general sense of steepness. Being non-numeric, they are less useful to a scientific survey than contours, but can successfully communicate quite specific shapes of terrain. They are a form of shading, although different from the one used in shaded maps.
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Dufour map of Bern (1907); this is a shaded hachure map. Hachures, first standardized by the Austrian topographer Johann Georg Lehmann in 1799, are a form of shading using lines. They show the orientation of slope, and by their thickness and overall density they provide a general sense of steepness. Being non-numeric, they are less useful to a scientific survey than contours, but can successfully communicate quite specific shapes of terrain.
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Brittle fracture in glass Hard products like ceramic pottery and glass windscreens can be studied using the same SEM methods used for metals, especially ESEM conducted at low vacuum. Fracture surfaces are especially valuable sources of information because surface features like hachures can enable the origin or origins of the cracks to be found. Analysis of the surface features is carried out using fractography. The position of the origin can then be matched with likely loads on the product to show how an accident occurred, for example.
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The image of a broken crankshaft shows the component failed from a surface defect near the bulb at lower centre. The semi-circular marks near the origin indicate a crack growing up into the bulk material by process known as fatigue. The crankshaft also shows hachures, which are the lines on fracture surfaces that can be traced back to the origin of the fracture. Some modes of crack growth can leave characteristic marks on the surface that identify the mode of crack growth and origin on a macro scale e.g.
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Topographic maps are based on topographical surveys. Performed at large scales, these surveys are called topographical in the old sense of topography, showing a variety of elevations and landforms.The range of information is indicated by the title of a map produced in 1766: A Topographical Map of Hartfordshire from an Actual Survey in which is Express'd all the Roads, Lanes, Churches, Noblemen and Gentlemen's Seats, and every Thing remarkable in the County, by Andrew Dury and John Andrews, reprinted by Hertfordshire Publications in 1980. This showed the relief by using hachures.
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The rules above are to be obeyed for large-scale maps. If the map being drawn is a small-scale map (less than 1:500 000 according to Imhof), rules may be relaxed in order to obtain a more suggestive representation. Hachures are still used today on Large Scale maps to show slopes and on British Ordnance Survey Maps and also in various countries toposheets to show Road and Railway Cutting and Embankments. On British OS Maps they have become long triangles with the short base at the top, and always pointing downwards.
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At Chatham he had charge of the chemical laboratory, and his experiments enabled him to perfect the selenitic lime which goes by his name. His system of representing ground by horizontal hachures and a scale of shade was perfected at Chatham, and adopted for the army as the basis of military sketching. During his residence at Brompton, Kent, a drought occurred, and he assisted in establishing a waterworks in the Luton valley. On 19 May 1863 Scott was promoted to be brevet major, and on 5 December of the same year to be regimental lieutenant-colonel.
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