By WB Yeats (biography in Wikipedia)
The trees are in their autumn beauty,
The woodland paths are dry,
Under the October twilight the water
Mirrors a still sky;
Upon the brimming water among the stones 5
Are nine and fifty swans.
The nineteenth Autumn has come upon me
Since I first made my count;
I saw, before I had well finished,
All suddenly mount 10
And scatter wheeling in great broken rings
Upon their clamorous wings.
I have looked upon those brilliant creatures,
And now my heart is sore.
All’s changed since I, hearing at twilight, 15
The first time on this shore,
The bell-beat of their wings above my head,
Trod with a lighter tread.
Unwearied still, lover by lover,
They paddle in the cold, 20
Companionable streams or climb the air;
Their hearts have not grown old;
Passion or conquest, wander where they will,
Attend upon them still.
But now they drift on the still water 25
Among what rushes will they build,
By what lake’s edge or pool
Delight men’s eyes, when I awake some day
To find they have flown away? 30