Valmiki Ramayana Kishkindha Kanda Sarga 42 Shloka 21
Original Shlokaपावकार्चिः प्रतीकाशास्समवेतास्सहस्रशः।।4.42.21।। नात्यासादयितव्यास्ते वानरैर्भीमविक्रमैः।
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सहस्रशः in thousands, समवेताः assembled together, प्रतीकाशाः appearing like, ते you, भीमविक्रमैः with very brave ones, वानरैः by monkeys, नात्यासादयितव्याः not to go very close to them, पावकार्चिःwith fire likeglow
'Collected together in thousands, and radiating like fire, they live there. Even the very brave vanaras should not go close to them.