Analysis of Now I am a Plant, a Weed...

Now I am a plant, a weed,
Bending and swinging
On a rocky ledge;
And now I am a long brown grass
Fluttering like flame;
I am a reed;
An old shell singing
For ever the same;
A drift of sedge;
A white, white stone;
A bone;
Until I pass
Into sand again,
And spin and blow
To and fro, to and fro,
On the edge of the sea
In the fading light--
     For the light fades.

But if you were to come you would not say:
"She is not waiting here for me;
She has forgotten."  Have we not in play
Disguised ourselves as weed and stones and grass
While the strange ships did pass
Gently, gravely, leaving a curl of foam
That uncurled softly about our island home,
Bubbles of foam that glittered on the stone
Like rainbows?  Look, darling!  No, they are gone.
And the white sails have melted into the sailing sky...