Valmiki Ramayana Sundara Kanda Sarga 9 Shloka 33
Original Shlokaदीपानां च प्रकाशेन तेजसा रावणस्य च। अर्चिर्भिर्भूषणानां च प्रदीप्तेत्यभ्यमन्यत।।5.9.33।।
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दीपानाम् of the lamps, प्रकाशेन by the glow, रावणस्य Ravana's, तेजसा च and by his brightness, भूषणानाम् of ornaments, अर्चिर्भिः च by the glow spread there, प्रदीप्ता इति as if glowing like fire, अमन्यत he thought in his mind.
Hanuman fancied that the entire place was set ablaze with the glow of lamps, the lustre of Ravana and the brilliant glow of Ravana's ornaments (everything was shining).