FYI the poet was Henry Scott Holland and this is the poem President Reagan was referring to:
"I am standing upon the seashore. A ship at my side
spreads her white sails to the ocean. She is an object
of beauty and strength. I stand and watch her until
at length she hangs like a speck of white cloud just
where the sea and sky come to mingle with each
other.
Then someone at my side says: "There, she is gone!"
"Gone where?"
Gone from my sight. That is all.
Her diminished size is in me, not in her. And just
at the moment when someone at my side says:
"There, she is gone!" there are other eyes watching
her coming, and other voices ready to take up the
glad shout: "Here she comes!"
And that is dying."
I read that poem after my mother in law's funeral to close family and friends. It's beautiful.