Of his professional experience we know little, save that he practised for a time in Philadelphia and Nashville, but, finding the profession unsuited to his health, he went to New Orleans and studied law. He was admitted at the bar in that city, but did not devote himself long to his new pursuit. He obtained a place on the _Crescent_ newspaper, and gave himself up to the fascinating business of journalism with all the ardour of a novice. That a man should have tried three professions so different as those of medicine, law, and journalism, before reaching his twenty-fifth year is not remarkable in our country. It was equally in keeping with the character of the man of 1849, that he forsook this latest fancy to join the host of restless spirits bending their steps towards California. Arriving there in 1850, he became an editor on the _San Francisco Herald_ and took sides with the faction of which David C. Broderick was the leader. His literary style was not ill-adapted to the journalism of the day and place, and ere long Walker the advocate found occasion to defend Walker the editor upon a charge for contempt of court. The lawyer failed to save the writer from the penalty of a brief imprisonment and a fine of five hundred dollars. The same pugnacious qualities involved him in a more serious quarrel with a Philadelphian, named William Hix Graham, and appeal was taken to the court of honour. The combatants met on a sandy lot outside of the city limits. Shots were exchanged, apparently without damage to either man, and the seconds were about to give the signal for another fire, when one of them perceived a pool of blood at Walker's feet. The doughty fighter had received a wound in the foot, and, in order to gain another shot, had tried to hide it by throwing sand over the spot with his other foot. The seconds, however, decided that honour was satisfied by the flow of blood, and the duel went no further. After this Walker retired from journalism, and practised law for a time in Marysville, with success enough to satisfy the ambition of anybody who aimed at law-expounding rather than law-making.