Mattang

This is a mattang, the Polynesian "compass". Like many other sailors, the Polynesians used the sun and stars, cloud formations and flights of birds to navigate over large expanses of open ocean (can you guess why clouds and birds could be helpful in finding land?). But the Polynesians also learned how to read wave patterns. Throw a stone into the water and what happens--the stone sinks of course, but circles of waves are made centred on where the stone fell. In much the same way, waves in the sea hit an island and are reflected back. The mattang is a tool showing all the basic patterns that waves can form when they bounce off land. An experienced Polynesian sailor would be able to read the wave patterns and tell which direction to go to find land. Stationary cloud formations, caused by temperature changes when cool sea air passes over warmer land areas, and the presence of many birds, show land is not too far away even if it cannot yet be seen.