Making the Invisivible Visible in a Map
Students are introduced to the practice of "Ekphrasis" to practice "reading" an image/photograph.
Making the Invisivible Visible in a Map
💡 Concept
When you look at a traditional map, you are usually looking at things you could theoretically walk up to and touch: a river, a mountain range, the border of a city. But medical cartography requires mapmakers to do something akin to magic: they have to make the invisible visible.
You cannot see "cholera" immersing in water. You cannot physically touch a "mortality rate." To put these abstract, terrifying, and invisible threats onto a physical landscape, mapmakers have to invent visual conventions. They have to decide what a disease looks like on paper. Is it a dense cluster of black dots? Is it an angry red shaded region? Or is it represented by a monstrous cartoon mosquito? By studying these formal choices—the symbols, colors, legends, and illustrations—we stop reading maps as simple reflections of reality and start reading them as deliberate, subjective arguments designed to persuade, warn, or control.
🖥️ Activity
Your task is to go hunting for the invisible. In this lab, we will get acclimated to our primary sources by focusing entirely on symbology and formal elements. We will use the embedded Mixtape viewer to scan the "Maps and Medicine" collection. Instead of looking at the geography, you will look specifically at how the cartographers chose to visualize disease and death, isolating these visual conventions using the cropping tool.
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👓 Examples
Notice how drastically the "feel" and meaning of a map changes based purely on the formal conventions chosen to represent the data:
- Point Data (The Dot Matrix): Marking individual deaths with dots or bars treats disease as a series of specific, quantifiable tragic events. It turns the map into a forensic crime scene.
- Choropleth (Color Shading): Shading entire regions with dark, ominous colors suggests disease is an environmental miasma—a dark cloud hanging over a whole population rather than individual cases.
- Allegorical/Multimodal: Sometimes data fails, and mapmakers use illustrative art to anthropomorphize the threat, combining geography with emotional propaganda.
🧱 Materials
Explore the "Maps and Medicine" collection in the Mixtape viewer below. Zoom in on the legends, the margins, and the data points layered over the geography.
🪜 Steps
- Open a map in the Mixtape viewer.
- Look past the streets and coastlines. Hunt for the "invisible" data—how is the disease or health statistic actually drawn?
- Use the Cropping Tool to highlight a specific symbol, a section of the legend, or a dense cluster of data.
- Copy the cropped image to your clipboard. Repeat this to grab a second, contrasting example from a different map in the collection.
✉️ Share
First post instructions: Submit a reply in this forum featuring your 2 cropped image details. Write a brief reflection (approx. 150 words) answering the following:
- What specific visual conventions (color, shape, text, illustrations) did the mapmakers use to represent disease in your cropped images?
- How do these two approaches differ in the emotional or intellectual argument they are making to the viewer? (e.g., Does one feel scientific and detached, while the other feels urgent and terrifying?)
Post by [Insert Date/Time]
Collaborate
Response instructions: Review the visual evidence posted by your peers. Reply to at least one classmate who chose a map you did not look at closely. What is one assumption a person living in that era might make about the disease based entirely on how it is drawn in your classmate's cropped image?
Interact by [Insert Date/Time]