But ill health prevented him from practicing his profession, and in 1845 he accepted an office in the navy department in Washington.
A few months later he became associate editor of the Washington Union, and was appointed by President Polk to be commissioner to the Sandwich islands to negotiate a treaty.
After several years of journalism he was appointed minister to Venezuela by President Pierce, and remained there until 1857, when he resigned and returned to Washington, where he practiced his profession until his death.
During the last five years of his life he attained a high reputation as an admiralty lawyer and for his knowledge of international law.
He was a fine linguist and scholar, and possessed remarkable conversational power.