His two desperate dashes for freedom secured O’Brien a place in the most miserable subterranean casemate of Bitche. Nevertheless, after a year’s captivity this undaunted master’s mate once more escaped--this time in company with a midshipman named Hewson, a dragoon officer named Batley, and a surgeon named Barklimore. Having constructed a rope, they let themselves down from the three concentric walls of Bitche, a height of 200 feet in all, and got clear away. This time fortune was with O’Brien. He and two of his companions (the third, Captain Batley, fell ill at Rastadt and had to be left behind) crossed South Germany in safety, and reached the Austrian frontier not many miles from Salzburg. The local officials politely acquiesced in a transparent fiction by which the fugitives pretended to be Americans, and allowed them to proceed to Trieste, where they were picked up by a boat of the _Amphion_, one of O’Brien’s old ships. The third voyage of this much-travelled man had lasted from 15th September to 7th November 1808. We need not linger over his service in the Mediterranean on the _Amphion_, _Warrior_, and _Bacchante_. Suffice it to say that he became a lieutenant on 29th March 1809, and was promoted to the rank of commander on 22nd January 1813. He had seen much service during these four years, and had once been severely wounded in an unsuccessful attempt to board and capture a Venetian _trabaccolo_ off Trieste. The most important action in which he was engaged was Commodore Hoste’s victory off Lissa on 13th March 1811. On being promoted to the rank of commander, O’Brien had to return to England, no ship being available for him in the Mediterranean. He arrived at Portsmouth on 4th October 1813, and took for some months a well-earned holiday. He was in hopes of seeing service against the Americans, but the times were unpropitious. Both the Napoleonic and the American wars were coming to an end, and, like so many other energetic naval and military men, O’Brien found himself placed on half-pay in 1814. He only had one more turn of service afloat, in command of the _Slaney_, a 20-gun sloop, which cruised on the South American station from 1818 to 1821. The rest of his life--he was still only thirty-six years of age--was spent in enforced retirement: in the thirties and forties the navy was kept low, and there was little prospect of work for the half-pay captain.