Known as "Old Man Eloquent," he died in 1848 on the floor of Congress.  
For unknown reasons his mastery of French at the age of 14 got him an appointment as interpreter and secretary to Francis Dana, U.S. envoy to Russia.  His later travels were the subject of his Letters to Silesia, though he had already gained note as Publicola, a journalistic supporter of France over Britain.  His work continued with the setting the groundwork for Rush-Bagot after he had headed negotiations at Ghent. Known as "Old Man Eloquent," he died in 1848 on the floor of Congress.  FTP, name this man who served as a Representative after serving, from 1825 to 1829, as the sixth president of the United States.
For unknown reasons his mastery of French at the age of 14 got him an appointment as interpreter and secretary to Francis Dana, U.S. envoy to Russia.  
John Quincy Adams