http://collections.lib.uwm.edu/cdm4/item_viewer.php?CISOROOT=/agdm&CISOPTR=864&CISOBOX=1&REC=9
Although I sifted through numerous maps, charts, and diagrams in preparation for this assignment, I ultimately settled on A.F. McKay’s 1889 “Man of Commerce” chart. The map provides an ideal object for this activity: it contains both visual and textual information, is highly detailed, and shows multiple variables, a lá Tufte. Perhaps most pertinently, it is unabashedly rhetorical. Finally, it’s quirky and interesting, making it an ideal candidate for in-class presentation.

McKay’s chart is an unusual conflation of nineteenth-century trade routes in North America and the human bodily systems, as the note beneath the title explains: “The resemblance between the arteries of commerce, as represented by railroads, and the arterial system of man; also, the resemblance between the great vital organs of man and the commercial system of the great lakes.” The main rhetorical purpose of the map is made fairly clear by both the accompanying text and main visuals, which place the major bodily organs—heart, brain, lungs—on top of North American centers of trade. More specifically, the map is a visual argument for the central importance of West Superior, Wisconsin, to the national and international economy.

“The Man of Commerce” adheres to many of Tufte’s principles of analytical design, yet still manages to be of dubious accuracy (at least to modern eyes). For example, Tufte laments modern chartmakers’ tendency to omit sponsorship information; in that light, McKay’s map is almost charmingly upfront about its affiliations. “Note that West Superior, Wisconsin, the head of Lake Superior, is at the heart of this wonderful man, the center of this great railroad and commercial system” reads the text below the title note, which is followed by the words “Land and River Improvement Co., West Superior Wisconsin.” Although this text is small in comparison to the graphics, it is placed fairly prominently beneath the title information, and is even printed in red (for the “note”) and larger black caps (the land company), which draws attention to the interested nature of the map’s sponsors.

The chart makes credibility claims by adhering—at least in part—to mapmaking conventions. Coastlines, rivers, and some mountain ranges are drawn realistically; labels follow the curves of rivers; different typography is used consistently for different types of elements; a key to railroad abbreviations is given in the lower left-hand corner. The diagram of the human body is also fairly conventional in its shading of the musculature and use of gently curving labels placed on top of organs. By adhering to conventions of both human anatomy drawings and maps, the mapmaker attempts to bolster the map’s central claim that the West Superior area is a hub of commercial activity. Since both the map and the anatomy drawing use conventions that connote scientific accuracy, the map suggests that the connection between the human body and the trade routes is a natural fact that actually exists, as opposed to a fanciful metaphor to explain trade routes. In addition to its central claim about the importance of West Superior, the map’s rhetoric also suggests a Western and specifically North American teleology that reads North American industry as the height of human endeavor. Further conclusions could be drawn about the placement of the body’s feet near Africa, Spain, and the British Islands, as well as the almost wholesale exclusion of the American south from the body. The map’s explanatory note underscores the Western-centric nature of the map by smugly concluding: “It is an interesting fact that in no other portion of the known world can any such analogy be found between the natural and artificial channels of commerce and circulatory and digestive apparatus of man.”The map, in choosing to represent trade routes as compared to the human body, also conveys attendant liberal humanist assumptions about the central importance of both the human and commerce, to say nothing of the fact that the body depicted is a male body.

Tufte suggests that offering multiple variables for comparison is an important feature of analytical design. In McKay’s map, the human body and trade routes are the obvious variables being compared, but the map is detailed enough to break those categories into more variables for comparison. Red arteries are labeled as both arteries and railroads, but in some places arteries are also labeled as steamship routes. The map also labels major organs, and in many cases gives labels for natural resources. Natural resource labels tend to be more prominent when they are placed near major organs: “iron” is prominently placed on top of the heart, while “silver” and “gold” are located in the brain. The chart thus offers a fairly rich visual experience that allows viewers to compare various aspects of trade and the human body, and to gauge the relative importance of a given location or item by seeing where it appears in relationship to the body.

While the map seems to base its representation of natural resources at least somewhat on reality, the representation is not numerically driven, making documentation a design aspect that the map fulfills only partially. Being neither a professional cartographer nor a doctor, I can only speculate about how much McKay had to stretch the representation of the human body systems or the railroad systems to make this design scheme work. However, the map itself gives some clues to the arbitrariness of the scheme: the map includes railroads that don’t fit within the diagram of the human body, but these are less obvious, as they have not been colored red. McKay also does not list sources regarding the anatomical correctness of his body diagram—is his diagram based on a reputable medical text? Did he use some kind of consistent scale in representing organs and arteries? (One supposes that as a mapmaker he is more familiar with correctly representing geography.) The map does not answer such questions, but simply looking at the map offers some clues: the scale of the human body compared to the North American map is chosen according to the size necessary to make the overlay with trade routes work. Also note the slight angle of the top arm, which has been shifted up to accommodate railroad lines to Alaska. In a typical medial diagram, arms would be either set at the same upright angle, or more likely, shown next to the torso.

“The Man of Commerce” is a revealing juxtaposition of solid visualization techniques and ingenuity paired with flawed implementation and questionable motives. The map’s visuals are executed fairly well and do effectively show what the mapmaker hoped to demonstrate. The point is eminently clear. Still, the overall reliability of the map is dubious at best. While “The Man of Commerce” is delightfully quaint to modern eyes, at the same time it demonstrates the potential for chartmakers to credibly present erroneous information through skillful use of conventions.