Edith Wharton - The Sonnet

PURE form, that like some chalice of old time
Contain'st the liquid of the poet's thought
Within thy curving hollow, gem-enwrought
With interwoven traceries of rhyme,
While o'er thy brim the bubbling fancies climb,
What thing am I, that undismayed have sought
To pour my verse with trembling hand untaught
Into a shape so small yet so sublime?
Because perfection haunts the hearts of men,
Because thy sacred chalice gathered up
The wine of Petrarch, Shakspere, Shelley -- then
Receive these tears of failure as they drop
(Sole vintage of my life), since I am fain
To pour them in a consecrated cup.

Edith Wharton

http://www.poemhunter.com/poem/the-sonnet-4/