4) What does Hart Crane mean when he writes, "It is all hung by an invisible white hair. It trembles as birch limbs webbing the air" (Crane 14-15). Who or what is he referring to?

Poem: My Grandmother's Love Letters

There are no stars to-night
But those of memory.
Yet how much room for memory there is
In the loose girdle of soft rain.

There is even room enough
For the letters of my mother's mother,
Elizabeth,
That have been pressed so long
Into a corner of the roof
That they are brown and soft,
And liable to melt as snow.

Over the greatness of such space
Steps must be gentle.
It is all hung by an invisible white hair.
It trembles as birch limbs webbing the air.

And I ask myself:

'Are your fingers long enough to play
Old keys that are but echoes:
Is the silence strong enough
To carry back the music to its source
And back to you again
As though to her?'

Yet I would lead my grandmother by the hand
Through much of what she would not understand;
And so I stumble. And the rain continues on the roof
With such a sound of gently pitying laughter.