Monsoon and Navigation of the Indian Ocean (During the period from 11th to 15th Century AD)

Trade in the Indian Ocean has been done according to the vagaries of the monsoon. The merchants had to travel from region to region with appropriate rigging of sails across the monsoon. It is noteworthy that the institution of ports in the Indian Ocean was done in the route of the monsoon. As Sri Lanka also was an island in the Indian Ocean trade route, it was a convenient lodge for ships travelling with the monsoon. There is ample evidence that merchant ships arrived in Sri Lanka constantly from the western and eastern regions of the Indian Ocean. These ships had travelled in the Indian Ocean in daytime without the aid of mariner’s compasses, and during the night following the stars. A special study has to be made on the period they came to Sri Lanka, purpose of the visit, the navy port and the period of trade barter, which are important. For this purpose, it is necessary to consider such environmental factors as monsoon, ocean current, and the shipping ports in Sri Lanka, and the nature of the ships. This chapter proposes to take up such matters in depth. It has been discovered that because of the monsoon trade in the coastline of Asia has progressed along 03 commercial zones, viz. Arab Oceanic Zone – North-east Africa, southern middle-east and the western coast of India. , Bengal Zone – Coromandel coast, Andhra, Orissa, Bengal, Burma, Thailand and the western zone of Malay peninsula, Sumatra, Borneo and the Philippines. , South China Zone – From Canton in China up to the Malacca Straits, Thailand, Eastern Malay Peninsula, Sumatra, Borneo, Philippines including Indo China.