Ca r t o g r a p h i c G r o u n d s
PRINCETON ARCHITECTURAL PRESS | NEW YORK
TABLE OF CONTENTS
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Foreword, Mohsen Mostafavi Introduction: Projecting the Landscape Imaginary Notes on Scale
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01 Sounding / Spot Elevation
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02 Isobath / Contour
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03 Hachure / Hatch
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04 Shaded Relief
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05 Land Classification
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06 Figure-Ground
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07 Stratigraphic Column
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08 Cross Section
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09 Line Symbol
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10 Conventional Sign
250 253 257 261 270
Afterword, Antoine Picon References Credits Index Acknowledgments
Foreword
THE CARTOGRAPHIC IMAGINATION M o h s e n M o s ta fav i
The work of an architect or a landscape architect is always situational. We imagine things in the same way a novelist constructs a piece of fiction. But the novel is an end product in its own right, as is a painting or a piece of sculpture—all ready for engagement at the moment of completion, to be read, seen, and encountered. In a novel, the concept of action is incorporated into and inseparable from the story being told; in architecture and landscape architecture, however, we design things through a set of drawing conventions—plans—that only later might become buildings or landscapes—places. The plan, as a form of drawing, is the description of a site that is to be constructed for a particular form of imagined purpose—a house, a hospital, a cafe, a park, a plaza. The drawing of each of these places refers at once to a condition of typicality as well as uniqueness. The house perhaps reminds us of other houses and yet is a particular locus—home— with its own specific set of qualities and characteristics. The qualities and characteristics of a house are temporal and subjective, attuned to the nuances of inhabitation and use. Yet the architecture of the house may also present a form of autonomy independent of its functional conditions. Equally, the plan is not produced solely in the service of actualization as building. By using a certain set of conventions, such as scale and method of representation, the plan also makes itself understandable as a project—a drawn idea. We can see thick or thin walls, the size and arrangement of the dining room, as well as the relationship and configuration of spaces. The house might also exist in relation to a particular topography. The map of this topography will perhaps be an important catalyst for reconciling the architecture of the house with the particularities of a specific location. And maps, like novels, use a certain set of conventions to construct the stories of places and topographies. Changing the scale of a map can reveal or occlude a host of information about a particular area or district. The cartographic imagination is therefore a specific mode of description of topography. Early maps, like the medieval mappas mundi,
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based more on fiction than fact, were a way of visualizing a world yet to be charted. Yet they provided the most accurate maps of the time and helped shape European intellectual life for more than three hundred years. The advancement of technology has brought about the possibility of greater proximity between the real and its representation. There still remains, however, the challenge of translating three-dimensional information into a two-dimensional surface, including the necessity of misrepresentation as a means of getting closer to the perception of the real. What are the tools, conventions, and scales that we should employ in order to tell the story, describe the characteristics of a particular territory, including even the narrative of dynamic change and transformation? The cartographic imagination is a study of the importance of multiple representations—of seeing and depicting various realities depending on the relevance of the occasion. A particular topography can, for example, be represented by its roads or by its undulating terrain or perhaps by a combination of the two. It all depends on the purpose of the map and the story it is trying to tell. The complexity of representing the world and its surface—oceans, vegetation, forests, cities, ravines, mountains, paths, hills, villages, and deserts—requires an equally complex set of conventions. A knowledge of these conventions enables us to participate in the world. We carry maps when we walk the countryside, visit a foreign city, and travel the subway. The map is the catalyst for the actualization of the territory. But the minutiae of cartographic conventions also have the capacity to help us imagine fragments of new landscapes, cities, and houses. Like words—the tools of the novelist—cartographic conventions can enhance the repertoire of a designer in articulating the space between the plan and its actualization. The understanding and experience of contour lines as a cartographic convention, for example, becomes a necessary tool for designing new landscapes. The interrelationship between depiction and actualization, a key component of the cartographic imagination, is then inseparable from the interrelationship between what is given— topography—and what is yet to come—design.
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The drawing of a parallel between cartography and architecture is instructive. Each lies in the field of the practical arts; each is older than history; and each, since its beginnings, has been more or less under the control of its consumers. —Arthur H. Robinson, The Look of Maps, 1952
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Introduction
PROJECTING THE LANDSCAPE IMAGINARY
Cartographic Grounds revisits the depiction of geographic morphology as grounds of and for design through a series of foundational representational techniques associated with the two-dimensional depiction of three-dimensional conditions. This necessarily involves a historical and conceptual reunion of the plan and the map. In light of the ascendance of “mapping” and data visualization in design culture in recent decades, and the privileging of abstract forces and flows, Cartographic Grounds reimagines the projective potential of cartographic practices that afford greater proximity to the manifestation and manipulation of the ground itself. The cartographic strategies depicted here offer an instrumental array for describing various conditions: subsurface, temporal, aqueous, and terrestrial. These strategies are organized in a series of ten chapters: sounding/spot elevation, isobath/contour, hachure/hatch, shaded relief, land classification, figure-ground, stratigraphic column, cross section, line symbol, and conventional sign. These ten historical cases are at once analytical and projective, precise yet speculative. Taken together, they form a rich symbolic language capable of describing existing and imagined grounds for the landscape imaginary. The mapping and visualization of data in design culture has changed the way architects, landscape architects, and urban designers communicate ideas about buildings and landscapes. Projects are supported by the widespread availability of physical and cultural data, and the translation of this data into visual documentation is now a ubiquitous component of the design process. The trajectory of representation—of concept and context— has moved from the material and physical description of the ground toward the depiction of unseen and often immaterial fields, forces, and flows. This has resulted in an important critique of geographical determinism within design culture, privileging, however, the intangible over the material conditions of the site. Between these two schools of thought—the purely geographic and the freely abstract—is a representational project that merges spatial precision and cultural imagination. Herein lies the
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You only understand information relative to what you already understand. You only understand the size of a building if there is a car or a person in front of it. You only understand facts and figures when they can be related to tangible, comprehensible elements. —Richard Saul Wurman, Information Anxiety, 1989
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NOTES ON SCALE
Cartographic Grounds invites close inspection of drawings, maps, and plans. Many of the drawings included here are remarkable for their engrossing tactility and engaging detail. The maps and plans are fragmentary and episodic, seeking the situated particular over the general. There are no drawings of the globe or even a continent in this volume. In many of these examples, it is possible to land at the airport or to arrive by boat, car, or on foot, and, even if it requires squinting, to find the nearest landmark. The scale of many equate to the scale of human occupation. It should be acknowledged that this level of detail is a privilege. Accurate surveying and high-resolution data are expensive. For example, the 1:25,000 topographical map (and its imperial sibling, the 1:24,000), are products of wealthy nations, either mapping their own territories or those of colonial interest. There is, and always has been, a correlation between power and the availability of geospatial data. In the United States, the 7.5-minute, 1:24,000 scale quadrangle1 is taken for granted. In fact, it is the most commonly recognized US geological-map scale. The five-color convention—black for culture, brown for contours, blue for water bodies, red for highways and urbanized areas, green for woodland and parks—is ingrained. There are fifty-seven thousand United Stated Geological Service 7.5-minute quadrangle maps covering the coterminous United States, Hawaii, and the US territories. (Alaska is not fully mapped, but maps are available for Anchorage, Fairbanks, and Prudhoe Bay.) One example, the San Francisco North quadrangle, is shown in comparison with five other 1:25,000 maps from across the world. Similarities arise, as brown contours, blue water, and green vegetation dominate, but there are also clear differences with the data, precision, and sociopolitical context of the maps. The currency of some maps rises above others, likely reflective of available resources. The maps of Nepal and Rhodesia are drawn at 1:25,000 but from coarser 1:50,000 surveys, including contours at twentymeter intervals (SEE CHAPTER 02) and emphasizing boundaries and roads over terrain information. The Indonesian map is drawn from 1:50,000 aerial photographs, with a contour interval of 12.5 meters to describe the
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relatively flat terrain. The taxonomy of land uses is coarse with an emphasis on infrastructure and exploitable natural resources. By contrast, the French focus on topography, with tighter ten-meter contours. The Swiss topographic maps have twenty-meter contours for legibility of the extreme topography on the paper 1:25,000 maps but offer frequently updated data digitally accurate to 1.5 meters for the entire country and to 0.5 meters in areas of open terrain. The maps are not only sophisticated in their rendering, combining shaded relief with vector line work, but are unparalleled in their precise quantification and qualification of the landscape. Scale is a powerful tool, one that relates subject and representation, governs content selection and detail, and indicates levels of measurement, knowledge, and access. The following six maps demonstrate the representational similarities and differences across a sample of large-scale topographic maps, revealing both conventional techniques and sociopolitical and economic divergences. They set the tone for the scale of maps and plans that follow, where the intimate prevails over the global, the tactile over the intangible, the precise over the general.
The “1:24,000” denotes the scale of the map, and “7.5 minutes” describes the area of the map as covering approximately 7.5 minutes of latitude and longitude. The total area covered on each sheet varies by geographical position, ranging from sixty-four square miles at latitude 30 degrees north to forty-nine square miles at latitude 49 degrees north. 1
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( pp. 20–21 )
0.1
United States Geological Survey,
37.7750° N, 122.4183° W,
Standard Symbols: Adopted by the
United States Geological Survey,
Board of Surveys and Maps United
San Francisco North, 1993. Scale:
States of America, 1932.
1:24,000 (shown at half size).
NOTES ON SCALE
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0.2 26.4833° N, 87.2833° E, Survey Department, His Majesty’s Government of Nepal (with the Government of Finland), Dhangadhi, 1997. Scale: 1:25,000 (shown at half size).
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0.3 6.3201째 S, 106.6656째 E, Badan Koordinasi Survei dan Pemetaan Nasional (Bakosurtanal), Serpong, 1990. Scale: 1:25,000 (shown at half size).
0.4 20.1667째 S, 28.5667째 E, Department of the Surveyor General, Zimbabwe, Bulawayo, 1977.
NOTES ON SCALE
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0.5 45.1900° N, 5.7200° E, Institut National de l’Information Géographique et Forestière, Grenoble, 1992. Scale: 1:25,000 (shown at half size).
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0.6 46.0167° N, 7.7500° E, Bundesamt für Landestopografie, Zermatt, 1997. Scale 1:25,000 (shown at half size). Reproduced by permission of swisstopo (BA140296).
NOTES ON SCALE
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CH A P T ER 01
SOUNDING / SPOT ELEVATION Soundings mark the depth of water measured at a point with a pole or line weighted by lead and noted by a number on a nautical chart at that point. A spot elevation is a number on a map that shows the position and the altitude of a point above a given datum.
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n any system of points, the relationship between measurement and drawing is a direct, scaled translation. The physical point of measurement correlates to a representational mark—a number, a cross, a dot, or a circle on a drawing. In bathymetric and topographic representation, the sounding and the spot elevation are points that denote relative elevation. Spot elevations are points above mean sea level, which is a common, but not universal, datum. Those below are soundings. Points in space and time mark physical and temporal locations within a landscape and are transferred onto paper, or screen, as points on a map or a chart. The resulting constellation reflects both the system of measurement and the complexity of the landform or surface being measured. Points are located and measured systematically by scanning visually, mechanically, or audibly. In cases where the ground is visible, elevations are determined by sight and measured—from mountaintop to mountaintop, river bend to river bend, and built form to built form. Corresponding points are marked and located mathematically through vertical and horizontal triangulation. In cases where the ground is obscured, a predetermined set of rules dictates the surveying approach. For example, the measurements are taken radially at regular intervals from a ship’s anchor point or are taken in a grid circumscribed atop a frozen lake. The geometry of these measurement systems translates to the map or chart drawing. The means of deploying the points becomes an overlay on the landscape, where the system can either converge or diverge with the inherent geographical organization. Thus, when following a shoreline or filling an entire water body with soundings, the physical landscape drives the location. Conversely, with the radial array and the grid, the points represent an independent system superimposed on the land. [FIG. 1.1] Literal geographic representation is pitted against scientific precision, selective editing over complete coverage. The representations are alluring, less for their clear depiction of underwater surfaces than for their potential to reveal and inspire spatial relations. Topography is hard to read through point distribution alone, but the points do uncover the intricacies of the landscape, the relationships between elements, and the corresponding methods of measurement. Spot elevations are often used to describe land in concert with other representational means—leaving the spot to mark only absolute high and low points and key landmarks in a drawing. Spot elevations indicate landscape complexity, with more spots correlating to greater intricacy and variation in the landscape. The point corresponds to the height of a significant feature, and the entire terrestrial landscape can be described
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through their distribution. However, the points are rarely left to stand alone. They are often connected either to form isolines (contours and isobaths [SEE CHAPTER 02] ) or to reveal the underlying triangulation. Triangulation is a common surveying technique, used both by the earliest national surveys and by the more recent global positioning systems, to locate the coordinates for features in the landscape by measuring the angle to a point from known points on a baseline. The network of points and triangles is then connected to construct a map of a larger territory. Triangulation continues to be a means to describe landscape surface. While disengaged from the immersive survey of the territory, digital terrain models use triangulated meshes to define complex geometry. The underlying wireframe can be extracted as a means to describe existing and proposed landform. [FIG. 1.8] The outputs of both early computer mapping and contemporary point clouds—a set of data points located within a three-dimensional coordinate system—reveal the plasticity of the point as a representational tool. The density of a field of dots is infinitely variable but can bear a direct relationship to characteristics of the landscape. Limited by the availability of data and the sophistication of printers prior to geographic information systems, or GIS, early geospatial maps could only approximate topography. One method was to create grid cells and use the average elevation to generate a terrain reading. [FIG. 5.11] Each cell was assigned a dot density based on average elevation, and the agglomeration revealed a terrain of tiny pixels. The result yields a field of high and low cells, not spot elevations, and a representation of points rather than lines. The grid cells obfuscate the fluidity of the terrain, but the method tests the limitations of the point as a continuous field to describe geospatial characteristics. With technological advances, the field distribution has reached new representational heights in point-cloud scanning and visualizations. The seemingly infinite number points that can be extracted from scanning either the landscape itself or a three-dimensional model of the ground is stunning. Elevation points do not rest flat on the page but dance three-dimensionally as geospatially located, mathematically determined spots in a landscape. The sounding and the spot elevation have always required translation, enhancement, or augmentation to achieve visual clarity. The shape of the land is not evident in a flat field of points—often equally weighted, drawn as blue or black dots or crosses, or, at rare times, anchors. Points have values associated with them, and only through representational innovation are these numbers converted into a readable topography. Points read easiest as landmarks, peaks or valleys, embedded within a
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detailed map or plan, where they are meant to augment information without overwhelming a drawing. Or they are clearly understood as soundings, where the important information to convey is depth at any given point rather than a synthetic reading of a continuous underwater ground plane. Yet, with the point cloud and other field-driven spatial experiments, the point can transcend this limited role and, through threedimensional differentiation and graphic hierarchy, emerge as an alternative reading of surficial properties. Singular precision meets aggregated totality. This chapter explores the representation of the sounding and the spot elevation in their various roles and configurations—from the plan, chart, and map to the dot matrix and the point cloud—exposing the breadth of pointillist techniques across space and time.
1.1 Jill Desimini, Sounding Techniques:
Topographical Engineers
San Francisco, Detroit River,
[FIG. 1.5], Washington Hood and
Cape Cod, Squam Lake, 2014. After
Major J. D. Graham [FIG. 1.10],
Alexander Dallas Bache [FIG. 1.3],
and Bradford Washburn [FIG. 1.6].
United States Army Corps of
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1.2
( pp. 34–35 )
47.1167° N, 9.2000° E, Robert Gerard Pietrusko, Animation Still, 2012.
1.3 37.7166° N, 122.2830° W, Alexander Dallas Bache, Entrance to San Francisco Bay California, 1859. Scale: 1:50,000 (shown at half size). The United States Coast Survey— established by Thomas Jefferson in 1807 and now an office within the National Oceanic and Atmospheric Administration—is responsible for navigational mapping of America’s oceans, coastal waterways, and Great Lakes. Alexander Dallas Bache ran the Coast Survey from 1843 to 1867, expanding the scientific and geographic reaches of the agency. His coastal cartographic project of describing the coastlines is remarkable, producing some of the finest representations of the landwater interface. For example, the 1859 Entrance to San Francisco Bay California beautifully renders the urban coastline. The spot elevations increase in density at shallower depths, effectively delimiting the extents of navigation while intricately describing the water’s edge.
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1.4 37.7166° N, 122.2830° W, National Oceanic and Atmospheric Administration (NOAA) Office of Coast Survey, Entrance to San Francisco Bay California, 2009. Scale: 1:40,000 (shown at 1:100,000). San Francisco, through its sea level station monitoring facility, has the longest running continuous sea level record in America (since 1854) and is one of the most documented ports in America. While drawing techniques have advanced, and preoccupations have changed from navigational safety to sea level rise, the distribution of soundings and the articulation of the coastline in this 2009 NOAA map versus its predecessor from 1859 are remarkably consistent. Yet the contemporary version lacks the wonderful enigma of the 1859 map, rendering the land continuously tan and the water in shades of blue and white.
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CHA PTER 03
HACHURE / HATCH Lines, often short, following the direction of maximum slope, which in a series indicate shadow, relief, and texture.
H
achures—lines that perpendicularly fill the space between contours—are used to indicate slope and shadow in cartography. Designed as a reproducible alternative to tonal shading, the system is simple and effective. Despite advances in printing technology, the hachure refuses to go away completely. Through experimentation, this tried and true technique remains a means to depict terrain and shadow. In design culture, the hachure equivalent is the hatch, both of which derive from engraving. The hatch, originally a series of closely spaced parallel lines used to create shading, has evolved into patterned swatches of dots, lines, and shapes in architectural drawing practice. [FIG. 3.1] Rather than being used to describe shadow or topographic relief, the hatch describes textural and material qualities. Through time, specific marks have come to represent specific construction materials—for example, stipples and small triangles for concrete—producing a clear language shared among designers and builders. As a technique, the hatch is a close relative of the hachure; but as a concept deployed in plan and section, its cartographic cousin is found among land-classification techniques (SEE CHAPTER 05) . In cartography, the caterpillar-like forms of early hachures descend from a pictorial tradition of representing relief where hills and mountains were drawn in elevation (SEE CHAPTER 04) . These shapes were drawn intuitively and did not adhere to precise rules. Yet, despite the generalization of form in these early hachures, they mark a transitional moment of greater measure and precision in topographic representation, when surveying and drawing techniques advanced to better reflect the geographic location of key physical features. With time, hachures were derived directly from contours, following clear rules and becoming less subjective and dramatic. Two remarkably simple yet powerful systems emerged: slope hachuring and shadow hachuring. Johann Georg Lehmann, a Saxon military cartographer, is the father of the slope-hachure system that, according to Imhof, successfully tamed the “hachuring chaos.”1 Contours formed the basis of his system with evenly spaced hachures drawn strictly perpendicularly to contours and therefore in the direction of the steepest slope. Slope angle determined the thickness of the line or relationship of black to white. The steeper the angle is, the greater the percentage of black present and the darker the area of the drawing. With shadow hachures, the illuminated side has thin lines, and the shade side has bolder lines. Mountainous forms roll like ripples in fabric. While the hachured landform is instantly visible,
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graphic keys accompanied hachures in atlases, translating slope angle to hachure spacing. The resultant maps show how a concise system of lines alone can yield a rich depiction of the ground plane. The representation of hachures is experimental yet restrained. Color is rarely used, and when it is, a neutral brown tone is usually elected for all hachures. In even rarer cases, a variety of colors is used to represent differing elevations or ground conditions. Thus, experimentation occurs in the way lines are used to describe the form, rather than in the graphic variations of the lines themselves. For example, in situ cross sections (SEE CHAPTER 08) , considered a form of hachure that does not follow the direction of the steepest gradient, use the technique of cutting tight sectional slices through the landform to represent terrain. The result describes the topography with a series of closely spaced sections that are geographically positioned in plan. With the increase of two-dimensional line work being generated from digital three-dimensional modeling in design, representing topography through nontraditional contouring and hachuring has become prevalent. Cartographically speaking, however, the hachure still has limitations. Given that lines are drawn perpendicular to the contours, significant generalization of the landform geometry is required for legibility. Tight contour radii, showing rocky and rough terrain, must be smoothed to avoid hachure overlap. Thus, the contour alone, the skeletal backbone of the hachure, is a more precise articulation of topography. With the ability to produce even tones between contours, the hypsometric tint and shaded relief offer smoother readings of form and shadow. In spite of these limitations, the hachures demonstrate the power of the line alone and the ability to achieve complexity through restraint. The beauty of the hachure, as evidenced by the following examples, is found in simple variation and repetition of a single element. The representation does not overshadow the landscape it emulates but rather reveals it in a discerning manner. To date, the cartographic hachure, with centuries of refinement and harmonious abstraction, is a more sophisticated representational tool than the architectural hatch, whose patterns can be coarse and tend to verisimilitude. This chapter argues for an elevation of the hatch in design drawing through a stronger alignment with the hachure and its rich past.
Eduard Imhof, Cartographic Relief Presentation (Redlands, CA: Esri, 2007), 111.
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3.1 Jill Desimini, Hatch Typologies, 2014.
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3.2
3.3
( p. 76–77 )
47.1167° N, 9.2000° E,
46.2000° N, 122.1892° W,
maps do not represent terrain with
a thicker and longer line). The
Robert Gerard Pietrusko, Animation
Patrick Kennelly, Mount Saint Helens,
the traditional hachure; rather, they
cross-hatch is the descendant of
Still, 2012.
2011. Scale: approx. 1:15,000 (shown
show only the shadows cast
the hachure and the hatch but
at full size). Originally published in
by landforms through a parametrically
recognizes the inherent difficulty in
“Cross-Hatched Shadow Line Maps,”
varied cross-hatch mark. His maps
representing the continuity of
The Cartographic Journal 49, no. 2
are hybrids, using multiple terrain
terrain through discontinuous lines.
(May 2012): 135–42.
drawing techniques. Angle illumination
American geographer Patrick
determines the length and thickness
Kennelly’s cross-hatched shadow line
of the lines (a higher angle yields
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3.4
3.5
( p. 79 )
46.5592°N, 8.5614°E,
46.5592°N, 8.5614°E,
Johann Heinrich Weiss, Atlas
Guillaume-Henri Dufour,
Suisse. Le mont Gotthard et partie
Topographische Karte der Schweiz,
des Grisons, 1786–1802. Scale:
1833–63.
1:120,000 (shown at full size).
Topographische Karte der Schweiz,
Maps are collaborative efforts. The
more commonly known as the
Atlas Suisse was the vision of the
Dufourkarte, is the canonical example
wealthy industrialist Johann Rudolf,
of the shadow hachure technique.
who after seeing the Pfyffer relief
As director of the Eidgenössische
model [FIG. 3.6] was inspired to
Topographischen Bureau between
commission a modeling and mapping
1832 and 1864, Guillaume-
project to further describe the Alps.
Henri Dufour guided the creation
The final map is the creation of Johann
of this first state-sponsored
Heinrich Weiss, who used a terrain
topographical map of Switzerland.
model built by Joachim Eugen
Drawn from numerous trigonometric
Müller as the basis for his hachured
surveys, the Dufourkarte is a
terrain rendering. This pre-
unified work in twenty-five sheets,
trigonometric survey atlas relied on
allowing for the complete visualization
modeling to understand the mountain
of the entire country, setting
forms and to guide the representation
the precedent for subsequent Swiss
of them. Relief is represented through
mapping endeavors. The early
horizontal depiction, oblique lighting,
drafts of the Dufourkarte include
and hachuring. The hachures—unlike
contours, color, and detail up to
later, more systematic examples—
a scale of 1:50,000, but the
are random. They are not always drawn
published version is streamlined and
perpendicular to the contours; they
monochromatic, highlighting
cross in instances, and their gradation
the Swiss topography exclusively
is not even.
with hachures.
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