Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 68
Original Shlokaयं यं देशं समुद्रस्य जगाम स महाकपिः। स स तस्योरुवेगेन सोन्माद इव लक्ष्यते।।5.1.68।।
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सः that, महाकपिः great vanara, समुद्रस्य of the ocean, यं यं देशं to whichever place, जगाम went, सः सः those, तस्य his, ऊरुवेगेन by the speed of his thighs, सोन्मादः इव riotous with eddies, whirlpools and revolving foam etc.like, लक्ष्यते was seen.
Whichever part of the sea over which that monkey flew, it appeared as though it was riotous with eddies, whirlpools and revolving foam etc., stirred up by the speed of his thighs.