Shelley uses the following lines:
For after the rain, when with never a stain
The pavilion of Heaven is bare,
And the winds and sunbeams, with their convex gleams,
Build up the blue dome of Air --
I silently laugh at my own cenotaph
And out of the caverns of rain,
Like a child from the womb, live a ghost from the tomb,
I arise, and unbuild it again.
You can see that the sky is described as a "pavillion" (great hall), and one that the rain has emptied. The sky is a "blue dome" and the poet/speaker treates the entire world as a site of rebirth.