 Complete the following phrase:  OBrien was promoted to commander on 22 January 1813 and left Bacchante in April, returning to England as a passenger on Watkin Owen Pells Thunder. OBrien was without a command until 1818 but in 1814 published an account of his shipwreck on Hussar and his subsequent escape to Trieste. In 1818, after the end of the Napoleonic Wars, he was appointed to command the 20-gun HMS Slaney. He served on the South America Station and, after Admiral Sir Thomas Hardy was posted to the west, was senior commander on the Atlantic coast of this station. OBrien held this role during the early part of the 