The Walls of Gang-Behesht Fall

From C4.21, Gang-Behesht Falls to Kay Khosrow. It illustrates C4.21.36–44:

C4.21.36
They set the naphtha-covered beams ablaze;Stones rained on them from overhead through haze.
C4.21.37
The bow-engines resounded through the smoke;The bright sun darkened in its dusky cloak.
C4.21.38
The engines thundered; dust obscured the view,Till earth was indigo and heaven blue.
C4.21.39
Chiefs shouted; trumpeting elephants replied;Swords flashed, and massive gorzes shook each side.
C4.21.40
The sun and moon themselves seemed locked in fight,Raining down swords and army dust from height.
C4.21.41
The naphtha-covered woodwork caught and burned;By God’s command, the props to ashes turned.
C4.21.42
The walls seemed lifting feet to leave their base,Then fell like mountains toppling from their place.
C4.21.43
With them fell many Turkish warriors bold,Like drops of rain, down from the shattered hold.
C4.21.44
Caught in the sudden snare, their lives were done;So ends the turmoil of each luckless one.