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What makes the Palk Straits a formidable challenge to swimmers is the presence of deadly marine hazards, warm tropical seas team with all kinds of marine lite. The natural dwellers of these seas include sharks a terror to all swimmers. These could be either tiger sharks or the fierce hammer headed ones. Both are man-eaters. Then there are those panthers of the deep, the barracuda. They are powerful and mean and attack anything that moves. With a shark repellent one can hope to keep single shark at bay; with a rifle or with divers around; barracuda can be discouraged. But there is nothing one can do about the reptiles of the Indian ocean. Owing perhaps to the presence of the chain of rocks and sand dunes in this area known as Adam's Bridge, the snakes infest the seas. They are not only poisonous but deadly poisonous. Sea snakes will not bite a man unless he touches or hurts them, Then there were the practical problems which often seemed to me almost insurmountable. Travel between Indian and Ceylon is rigidly controlled.     (Mihir Sen)