Valmiki Ramayana Yuddha Kanda Sarga 20 Shloka 3
Original Shlokaएषवानरऋक्षौघोलङ्कांसमभिवर्तते । अगाधश्चाप्रमेयश्चद्वितीयइवसागरः ।।6.20.3।।
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द्वितीयः second, सागरःइव: like the ocean, अगाधश्च: deep, आप्रमेयश्च: and immeasurable, एषः that way, वानरऋक्षौघः Vanaras and Bears, लङ्काम् into Lanka, समभिवर्तते: are heading towards.
As if it is a second ocean deep and immeasurable, the ocean of Vanaras and Bears are heading towards Lanka (reported the spy).