Since iron was not yet discovered in the Bronze Age, the Meluhhan, the Mesopotamian and the Egyptian ships did not have mariner's compass at their disposal.
Therefore, did those ships traverse long distances on the sea by referring the North Star alone? Does it mean that their sailing period was restricted only to night time and clear weather when the North Star was visible? Submitted by Vasant Dave
The Harappan ships probably followed the coastline during daytime; in case they accidentally lost the way and came to open sea, they seem to have kept in their ships birds, which on being released flew towards land and thus showed the way. Cf. my book Deciphering the Indus script (1994) p. 14, fig. 1.10.