I’ve previously talked about my love of maps, particularly ones that are quirky or that take an unusual form. You got to see one of my underwater maps here. And, as a diver, I am always thinking about underwater navigation and how to move from point A to point B and how to return! Underwater maps and navigation play a huge part in my diving.

Recently, my small niece has become interested in stars, so we were discussing star maps and tools that help to guide you. I showed her a compass and a star map that shows you where stars are in the sky at a particular time of year. I mostly use the map on my phone or digital trail maps when I’m hiking to know where I’m going on land. But, I also carry a compass on my backpack so when I have time, I can practice navigating using a compass. I use the planisphere to know what I’m looking at when I’m stargazing, but knowing what stars are where can be an important navigational tool, particularly at night.

So, perhaps it’s no surprise at all that maps have made it into my novel as a theme. My main character is a diver and she is often thinking about how to get from one place to another.

In the course of my research, I came across two amazing kinds of maps that I didn’t know about before: the Marshall Island stick charts and tactile, driftwood charts known as the Ammassalik maps.

Meddo and Rebbelib: Marshallese Stick Charts

In the Marshall Islands, navigators used to make maps out of coconut fiber and small shells. These maps were called meddo or rebbelib. They were not so much land maps as ocean maps, a way of understanding the sea. I’m fascinated by this wayfinding—how to find one’s way—by mapping the ocean. We usually think of maps connected to places. But here, the maps show the water itself. Navigators created a map of islands, waves, and even the direction of the current moving through the water so that they could anticipate what to expect on the water.

But, they didn’t take the map with them: it was an exercise in memory. By making the map and then memorizing it, they were able to memorize where they were going and what they needed to think about to get there.

A mnemonic device, something that helps us to remember an important idea or concept, is common in learning. For instance, in diving, we use the silly phrase Big White Rabbits Are Fluffy to help us remember the steps in checking our gear before getting in the water. B stands for BCD, the jacket we wear to help us float and adjust to the weight of the water; W stands for the extra weights we wear; R stands for releases to make sure we know how to get ourselves and our buddies out of their gear in an emergency; A stands for air! We want to make sure we have LOTS of air before going under water; and F is for final check. Do we have everything we need for this dive?

So, the Marshall Island charts are a mnemonic device: they help navigators to remember the waters around them to help them get where they want to go. Memory devices are important. But, I’m sure, here, the act of making the chart helped a lot in memorizing it as well! You can see some photos of the charts here, at National Geographic. This short video from the American Museum of Natural History shows several maps and talks about their history.

Ammassalik Maps: Tactile, Carved Driftwood Maps

These fascinating small maps are completely tactile. They can be slipped inside a glove (a good thing, since they represent the coastline of Greenland!); they float if they fall into the water; and, like the meddo and rebbelib maps, these are nautical charts used to navigate the coastline.

While many variations probably existed, the ones we know the most about were carved carved by a Tunumiit hunter named Kunit in Greenland in the late 1800s. Historians believe these were not traditional maps used by the Tunumiit people but were carved for a Danish explorer named Gustav Holm.

I love the idea that you can hold the coastline in your hand, feeling it go by as you move along the waters. In the same way I don’t need a map to go from my house to school, because it’s a trip I take everyday, the Tunumiit people knew the geography of their land and could navigate it by natural navigation, memorizing important landmarks along the way. But, what’s fascinating about the driftwood maps is how Kunit translated that knowledge into a portable map for another explorer. You can see an example of how the carved maps line up with the coastline of Greenland here. And, this blog entry from National Geographic shows the maps along with some other examples of cartography (including the Marshall Island stick charts!)

I think both of these maps are fascinating because they reveal a lot about how the makers view the world they live in and how intimately natural landmarks and nature (like the ocean swells) itself becomes a point of navigation and understanding how we can move through the world!

I’ve always been a fan of strange maps that show you things you didn’t expect. I also like thinking about maps that will surprise people. What kind of map would you make if you could? Is there a way you’d interpret the natural landmarks around you into a map? How would you explain things you think of as ordinary to someone who hasn’t seen it before?

(P.S.: For years, I’ve threatened to write a map (and travel guide!) to the BEST reuben sandwiches across the United States or pickles. I totally think we need a pickle map. Wouldn’t that be great?)