Tell me about this book then!

Day is ended, dim my eyes,
but journey long before me lies.
Farewell, friends! I hear the call.
The ship's beside the stony wall.
Foam is white and waves are grey;
beyond the sunset leads my way.
Foam is salt, the wind is free;
I hear the rising of the Sea.

Farewell, friends! The sails are set,
the wind is east, the moorings fret.
Shadows long before me lie,
beneath the ever-bending sky,
but islands lie behind the Sun
that I shall raise ere all is done;
lands there are to west of West,
where night is quiet and sleep is rest.

Guided by the Lonely Star,
beyond the utmost harbour-bar,
I'll find the havens fair and free,
and beaches of the Starlit Sea.
Ship, my ship! I seek the West,
and fields and mountains ever blest.
Farewell to Middle-earth at last.
I see the Star above my mast!