Cathy,
Welcome aboard!
Cameron's film seems to have made "Titanic" and "ship of dreams" go hand in hand. I can't say the origin of the comparison, but I can offer something. The Titanic musical, which first debuted months before the movie came to theaters, features the following lines in the song "There She Is."
BARRETT, BRIDE & FLEET: (looking at the ship, overwhelmed)
There she is...
Towering high...
Broad and grand...
Ship of dreams!
BARRETT, BRIDE, FLEET & CREWMAN:
Sailing day!
Morning bright!
Take your flight!
Ship of dreams!...
She strains at her lines,
The smoke from her funnels trailing.
Her prow like a knife,
She'll cut through the waves unfailing.
Soon to be
Underway,
Size and speed unexplored...
And I'll be aboard
That ship of dreams!
I hope that can help a little, for all it's worth.
Josh.