“This is an appeal from a pro forma decree of the district court, which dismissed the libel of the appellant, surgeon on board the Mercury, for salvage. The libel sets forth, that the ship sailed from Philadelphia to Calcutta in the year 1809, where she took in a valuable cargo, and on her return voyage, was, on the 8th of May 1810, when near the island of Madagascar, captured as prize by a French national frigate. That all the officers of the Mercury, the master, the carpenter, the two supercargoes, and the libellant excepted, and the whole of the crew, with the exception of three ordinary seamen and one boy, were taken out of her, and were replaced by a prize-master, two midshipmen and a crew of nineteen men, and she was ordered to proceed to the Isle of France for adjudication, under the Berlin and Milan decrees. Three attempts were made by the prisoners to retake the ship, in which the libellant took an active part . . .”