Two of Dana's companions for the trip were Thomas Gold Appleton, the "prince of rattlers," and William Wetmore Story, who was abandoning the law to study art. The trio talked and told stories, making half-formed plans to co-author a book called Spray from the Paddlebox. Appleton, who was a frequent traveler to Europe and elsewhere, called it "one of the pleasantest passages I have made." Dana described it this way:
We started punctually at twelve, with a most beautiful day overhead and around us... and we went down the harbor in beautiful style — actually bound to Europe, — the Europe of my dreams, that I hardly dared believe I should ever see. But now that the time has come, I am so intensely interested in my own country, in the impending struggle between the free classes and the slave-power that I cannot conjure up a thought of England.
Dana was already a founding member of the Free Soil Party and served as the lawyer defending fugitive slave Anthony Burns. The majority of his career for the next decade after his European trip was devoted to the anti-slavery cause, often serving as a pro bono lawyer for fugitive slaves.