As one of some fat tillage dispossessed,
Weighing the yield of these four faded years,
If any ask what fruit seems loveliest,
What lasting gold among the garnered ears, --
Ah, then I'll say what hours I had of thine,
Therein I reaped Time's richest revenue,
Read in thy text the sense of David's line,
Through thee achieved the love that Shakespeare knew.
Take then his book, laden with mine own love
As flowers made sweeter by deep-drunken rain,
That when years sunder and between us move
Wide waters, and less kindly bonds constrain,
Thou may'st turn here, dear boy, and reading see
Some part of what thy friend once felt for thee.

Alan Seeger

http://www.poemhunter.com/poem/with-a-copy-of-shakespeare-s-sonnets-on-leaving/