horizontally or tilted upright like books in a bookshelf. In Figure 7.2 patterns of land ownership and agriculture management are revealed in the patterns of tree hedgerows marking property boundaries or pasture plots. The hedgerows seem to follow lines of equal elevation or contours.
Contour Lines: A Language for Two Dimensions Contour lines are a human invention used just as are letters and numbers to communicate and describe the world. The word BREAD consists of a selection of symbols—letters in an alphabet—to communicate a physical object or an idea. The letters B – R – E – A – D when seen on a piece of paper by an English language reader are understood to represent a loaf or piece of bread. Both contours and numbers, when applied following a set of rules, can communicate something of meaning and can also allow the reader to visualize the shape or a landscape. However, the same symbols applied without a framework of rules will not produce understandable results. A writer who knows the conventions for assembling individual letters can create words, and by following sentence structure conventions—syntax—is able to create sentences that convey ideas or descriptions, emotions, and images of places, among other purposes. Like sentences, contours can be thought of as communication devices. In the case of contours lines, they are used to portray the three-dimensional shape of a landscape or designed outdoor environment. Contour lines are a graphic device used by designers to visualize or see landform (which is three dimensional) in two dimensions on a piece of paper or computer screen. The two-dimensional contour or topographic plans created by a designer are used to communicate the design intent—in the case of terrain modifications—to others such as clients, government design review boards, and contractors. Contour lines, together with spot elevations and a range of standard symbols and numeric and alphabetic annotations, are used to create site-grading plans. Contractors are guided by the grading plans in performing the required earth moving on a site to create the desired earth
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