Joy that's half too keen, and true,
Makes us tears.
Oh! the sweetness of the tears!
If such joy at hand appears,
Snatch it, give thine all for it;
Joy that is so exquisite,
Lost, comes not new.
One blossom for a hundred years.

Grief that's fond and dies not soon
Makes delight.
Oh! the pain of the delight!
If thy grief be love's aright,
Tend it close and let it grow:
Grief so tender not to know
Loses Love's boon.
Sweet Philomel sings all the night.

Augusta Davies Webster

http://www.poemhunter.com/poem/joy-that-s-half-too-keen-and-true/