Comparatives were popular through most of the 19th century, published across western Europe, the United States, and later in Japan. Comparative views evolved constantly as new information became available, as publishers sought new ways to differentiate their atlases, and as new ideas in data visualization emerged. Whereas the works of European and American cartographers’ drove the changes in the genre, Humboldt, Bertuch, and Perthes were standouts as innovative German publishers of comparative views.
Alexander von Humboldt shook up scientific data presentation when, in 1805, he published Geographic der Pflanzen in den Tropenlandern, ein Naturgemalde der Anden documenting his findings from his exploration of Mount Chimborazo in present day Ecuador. It was unique in that it displayed information corresponding to altitudes in relative position on a cross-section of a map. In the margins of the graphic he further annotated observations of physical phenomena and their corresponding altitudes. Where this style of visualization seems commonplace to 21st century information consumers, it was hardly such at the time; in the early 1800s visual display of data was in its infancy.
Learning of Humboldt’s chart and inspired by Goethe, Friedrich Bertuch prepared his Hohen der Alten in about 1810, publishing it in his Bilderbuch, a children’s encyclopedic volume. That he published it at all, what he displayed, and that it appeared in a children’s book, are important facts. That he published it signifies the embrace of the Humboldt’s cross sectional style as a means of describing occurrences at various heights. His view took a landscape form, with mountains arranged as though viewed from afar, generally with the larger mountains to the sides and background of the image, but didn’t end there. Stick figures show Humboldt and de Suassure on Mounts Chimborazo and Blanc, respectively, a crocodile at sea level, and Gay-Lussac aloft on his record setting balloon flight. By going beyond just mountain heights to show human accomplishments, Bertuch both ties human scale and geologic scale, as well as uses the comparative as a device to showcase human accomplishment. Plants and animals appearing on the comparative pull forward the thread that Humboldt wove whereby mountains are re-imagined as not just inert monoliths, but as parts of dynamic, living systems. By including his view in a children’s book, he recognized that this genre makes complex information accessible in a simple and easy to understand format.
Die Benkannteren Hoehen uber der Meeres Flache in Transparenten Profilen by Perthes is unlike the other comparatives. Mountains comparatives typically show their subjects side by side in descending order or in an overlaid descending sort. Perthes, on the other hand, shows the mountains overlaid in transparency so that one can see the contours of the mountains instead of them being obstructed by the mountains in the foreground, or reduced to conic figures. This innovation is noteworthy in that it signifies an interest in the entire mountain, rather than the peak in isolation. It also represented an innovation built on the line graph, placing geographic location on the x-axis. Interestingly, and perhaps because Perthes published this as the comparative genre was at its apex, this style of comparative never took hold.
To be sure, these German cartographers (or scientist in Humboldt’s case) made great contributions to the comparative view as a style between inspiring, giving rise to, and redefining the charts. They by no means were the only innovators: Darton in 1823 produced the first compound comparative, showing both mountains and rivers in the same panel; the Society for the Diffusion of Useful Knowledge published a unique circular rivers comparative; and Mitchell was possibly the first to add comparative elements to globular projections. All told however, their pieces are testimony to the good work coming out of German cartography.
© Peter Roehrich, 2016