Valmiki Ramayana Sundara Kanda Sarga 1 Shloka 16
Original Shlokaमुमोच च शिलाः शैलो विशालाः समनःशिलाः। मध्यमेनार्चिषा जुष्टा धूमराजीरिवानलः।।5.1.16।।
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शैलः mountain, मध्यमेन in the midst, अर्चिषा by the flame, जुष्टा:possed with, अनलः fire, धूमराजीरिव like the columns of smoke, समनः शिलाः along with sulphur pigments, विशालाः big one, शिलाः boulders, मुमोच threw out, च even.
The mountain threw down big boulders along with sulphur just like fire emits columns of smoke, surrounded by flames.