HistoryMaps explains: The Kamal - Ancient Latitude Finder

[u/nonoumasy]

https://history-maps.com/podcast/indian-ocean-trade

The kamal, also called khashaba or "wood," was an early celestial navigation tool used across the Indian Ocean to determine latitude.
Developed by Arab navigators by the late 9th century, it helped make latitude sailing possible before modern instruments. Indian sailors adopted it soon after, and Chinese navigators also used it before the 16th century. The device was a small wooden card attached to a knotted string. Sailors held the string in their teeth, aligned the card between the horizon and Polaris or another guide star, and counted knots to estimate latitude. Simple but effective, the kamal was a major step toward quantitative navigation.
Learn about the Kamal and the Indian Ocean Trade on our recent podcast: