NICHOLAS BIDDLE became the next editor. He supplied the magazine with a number of articles upon paintings, old and new, and resigned his charge early in 1812. Dr. Charles Caldwell was requested to succeed him. "I accepted the proposal," he says, in his "Autobiography," "in less than a minute, and in less than one hour began to prepare for the performance of the duty it enjoined" (_Autobiography_, page 322). Caldwell entered upon his task under an engagement to furnish ninety-eight pages of matter for each number, and this matter would have to be to a great extent original. In six months Caldwell increased the number of subscribers twenty-five per cent. The war naturally became the theme of greatest interest. General Brown declared that "he reported himself, and ordered his officers to report themselves in their connection with all interesting events of the army, as regularly to the editor of the _Port Folio_ as they did to him, or as he did to the Secretary of War." In this way the magazine obtained some interesting and valuable biographical notes of military and naval officers. Dr. Caldwell employed as assistant editor the famous and versatile THOMAS COOPER. Cooper was an Englishman, who was born in London in 1759, and had been a member of the National Assembly of France. He quarrelled with Robespierre, and challenged him to a duel. Robespierre swore revenge, and Cooper, knowing that flight alone could save him from the Jacobin Club, returned to England. He was censured by Burke, and replied in a bitter and abusive pamphlet. He followed his intimate friend, Mr. Priestley, to America and lived with him at Northumberland, where Coleridge and Southey dreamed of establishing an Eden of Pantisocracy. When Cooper came to Philadelphia, Washington and Jefferson and Jay and Madison were there. Cooper lent his pen to Jefferson and the Democrats, and was paid by them. He was appointed to a judgeship, but soon removed. He was elected professor of chemistry and moral philosophy in Dickinson College, and from there he went to the chair of chemistry in Columbia College, South Carolina. He left Philadelphia in 1819, and died in the South in 1840. JUDGE WORKMAN was a second assistant writer. The most extensive contributions that Dr. Caldwell made to the magazine were his reviews of "An Essay on the Causes of the Variety of Complexion and Figure of the Human Species," by Samuel Stanhope Smith, President of Princeton College. The reviews covered ninety pages and dealt with a philosophical and experimental examination of the strange case of Henry Moss, a Maryland negro, whose name, as Dr. Caldwell says, is as well known to the readers of periodicals as was that of John Adams or Thomas Jefferson or James Madison. Moss was a full-blooded African, whose skin, save in a few spots, turned white. Caldwell's critiques appeared in the _Port Folio_, 1814, pp. 8 and 457, and also in the _American Review_, II, 128, 166.