This is the second stanza of Yeats's The Two Trees in Sindarin:

Na cheledh haer avo diro,
ah i guru chall în in Ylynn
Eriar nef men reniol,
Egor tiro trî lû gidinn;
*An auth nagel tuia ’nnas
I gâd i dhaw nan alagos,
Gylf *rengin ar laiss vyrn,
Thynd berthyrin nuin loss.
An prestathar naid bain neithennin
Vi heledh dholl i hebir in Ylynn.
I cheledh e-*lôf *edui,
Echannen io, *ias *lorn Hêr,
Ennas reviar trî gylf rengin
I chrebain en-nauth benidh;
Reviol, nallol ennas a sí,
Gamp maug a lanc *haeg,
Egor derir hain, *thostar i ‘waew,
Rithar hain raifn nerchennin în,
Prestar úvel hent vilui lín,
Avo diro na cheledh haer.

[Edited per Gabor's and Bjorn's comments]

Gaze no more in the bitter glass
The demons, with their subtle guile,
Lift up before us when they pass,
Or only gaze a little while;
For there a fatal image grows
That the stormy night receives,
Roots half hidden under snows,
Broken boughs and blackened leaves.
For all things turn to barrenness
In the dim glass the demons hold,
The glass of outer weariness,
Made when God slept in times of old.
There, through the broken branches, go
The ravens of unresting thought;
Flying, crying, to and fro,
Cruel claw and hungry throat,
Or else they stand and sniff the wind,
And shake their ragged wings; alas!
Thy tender eyes grow all unkind:
Gaze no more in the bitter glass

-----
*an: conj. "for, because", cf. Q an
*rengin: pt. ppl. pl. of http://middangeard.org.uk/vqp/doku.php/ns:rag *lôf: n. "weariness" LUB- cf. the adj. lom (VT45)
*edui: adj. "outer" from ed- (not happy with this but can't think of better)
*lorn: adj. "asleep" LOS- VT45; asterisked because the form was deleted by Tolkien

All comments welcome.