In the 19th century, the Torres Strait Islanders did not have a numeral system and used sticks to keep counts. Sticks were tied to a string, forming a bundle (called kupe) that could be rolled and unrolled when needed. Kupes were typically used by men to keep track of their accomplishments, such as turtles caught in deep water, fishes speared, or adventures with women (as the one above). These physical visualizations were used as social […]

Women from the Yakama Native American tribe used strings of hemp as personal diaries. Each major event in their life was represented by a knot, a bead or a shell. This mnemonic device is called an Ititamat, or counting-the-days ball, or simply time ball. The first image shows an Ititamat created before 1920. On the second image, each string is a different Ititamat. The last image shows a 2003 replica. […]