Coastal Mnemonics

Zeyuan Ren

“You wonder if they, in the confused seas, also
created a mnemonic device, or mode of
map making, sensing, and memorizing the swell patterns in certain moments—bending, reflecting, disturbing, and refracting, then carrying with oceanic knowledge, onward to the sporadic groups of islands in the distance.”
This narration finds itself at the start of my recently completed essay film, Coast to Coast (Preamble).

What is a mnemonic device?
What can oceanic knowledge refer to?

I have often tapped on the Map application that came with my laptop and zoomed in and out as far as possible on the scale as a way of becoming aware of how long it really takes to get from one side of the Pacific to the other—using two fingers to swipe right on the trackpad to cross the ocean, digitally and roughly. The process was frequently disorienting before I even “landed” on the other side, since the Pacific Ocean is overwhelmingly massive.

After navigating a few virtual trips, I perceived that my journeys were attempts to bridge this body of water with a bird’s-eye view. Apple Maps offered me such a perspective—a quick way to access digestible, flattened information, or rather, knowledge. A digital map greatly surpasses a paper map in its ease of interaction and volume of data, but it still remains within the framework of a traditional cartographic paradigm, one which treats the ocean as a traversable, conquerable space which can be skimmed and overlooked.

We are always relying on traditional mapmaking—a land-centered cartographic code. Is there a map of the ocean, a cartographic counter-example, that opposes terrestrial cartography?

Last spring, I encountered a sculptural object called a “stick chart” at the Boston Museum of Fine Arts. It’s difficult to explain why I felt more drawn to these wooden pieces made of crossing bamboo fibers, shells, and twine, than to the other exquisite collections.

I didn’t realize at the time that their makers and users came from the scattered islands sprinkled in the azure that I happened to glimpse on the digital map; these stick charts are the work of navigators from the Marshall Islands. Some islanders in Oceania use elements such as the stars, the moon, or the wind, to guide their canoes to their destinations. By contrast, the Marshallese focus their observations on one environmental phenomenon nearby—that of the ocean. In a study of Marshallese navigation, Joseph H. Genz explains:

Marshallese navigation is a system of wave piloting, in which mariners pilot, or guide, their canoes by reference to swell and current pattern transformations that are used to remotely sense land. … With such an emphasis on an environmental feature (waves) that is in constant motion with changing direction, strength, and frequency, navigators must orient themselves through the practical activity of sailing out of sight of the home island and sensing the shifting configuration of myriad waves.1

I have no doubt that in this mode of piloting the navigator needs to be fully immersed and engaged in the act, using their senses as best they can to perceive the movement of the ocean itself. In addition to the eye (vision), ear (hearing), and body (touch), the human body’s sensory system of balance and spatial awareness is pivotal in Marshallese navigation. “Spatial orientation in Marshallese wave piloting centers on vestibular ways of knowing about the ocean,” Ganz writes.2 We can imagine that they have to sort through different wave patterns in a variable, uncertain, and contingent liquid environment, and use their sense of balance to “feel” how the canoe responds to the waves. The swing and rhythmic changes of the canoe signify a unique “sea mark” in the mind of the Marshallese, indicating the direction and distance to unseen islands.3

In my opinion, these people are the closest to understanding an oceanic knowledge which is both fleeting and without fixed form; through the embodied recognition of the voyage, I believe the Marshallese have glimpsed a unique form of knowledge, which is then represented as distinctive a cultural rendition in the artistic, physical form of the stick chart.

A stick chart appeared before me once again on the back cover of Tidalectics, the catalog of an exhibition of the same name, curated by Stefanie Hessler. As the image of the stick chart rests on the surface of the book as an imprint, rather than “seeing,” it would be more accurate to say I was “touching” it—my thumb followed the texture of the inscribed lines, trying to “trace” all the oceanic routes represented by it. I realized that these particular models of the ocean are, undoubtedly, the cartographic counterexample I was looking for; they emphasize a lived experience, as opposed to a view from above. Stick charts are more closely related to, and in correspondence with, place, not space.4

While reading several essays by various anthropology scholars, I realized that the act of “interpreting” stick charts is a somewhat futile endeavor. Each analytic text in the paragraph is followed by a diagram on a stick chart pattern which has been simplified, indicating the intricate complexity of each one. The true complexity of a stick chart can only be interpreted precisely by its maker. This exceptional mapmaking method is highly individual and exclusive, and acts as a non-shared vehicle of knowledge before which no empirical interpretation can be sustained.5 Furthermore, stick charts are only memorized and studied prior to the voyage, and would not be carried on board by voyagers in their canoes. In this regard, their functionality is completely distinct from the printed or electronic maps we use to consult, plan, and plot out routes as well as points during navigation; the stick charts were never seen as navigation tools, but rather as mnemonic devices embedded with personal experience and a unique travel story. Returning to my own work, throughout my film, the pronoun “you” is used to encapsulate the experience of my own journey through the narration. As such, the narrative and the experience of viewing the film become a retrospection; the combination of visual material of my coastal journey last summer serves as a time capsule, a distinct presentation of my own encounters within a place, waiting to be retrieved by my future self. Thus, Coast to Coast (Preamble) has become my own “stick chart.”

I always see myself as a storyteller who is “mapping” rather that “using” a map, as a way of  building and retrieving my own story. In this I retrace my own steps, but also the steps of my predecessors. Even now, the knowledge and instruments of creativity created by the Marshall Islanders profoundly influence my artistic practice and methodology, as I continue to seek my own mnemonics.


  1. Joseph H. Genz, “Resolving Ambivalence in Marshallese Navigation: Relearning, Reinterpreting, and Reviving the “Stick Chart” Wave Models,” Structure and Dynamics, vol. 9, no. 1 (2016): 14.
  2. Ibid., 14.
  3. Ibid., 15.
  4. Stefanie Hessler, Prospecting Ocean (Cambridge, MA: MIT Press, 2018), 72.
  5. George W. Playdon, “The Significance of Marshallese Stick Charts.” The Journal of Navigation, vol. 20, no. 2 (1967): 159–62.

Zeyuan Ren is wondering with the next stop would be.