Complex sentence: On her second voyage transporting convicts, under the command of George Bunn and surgeon J. Dickson, she sailed from The Downs on 23 March 1824, with 172 male convicts.
Split into simpler sentences: On her second voyage transporting convicts, she was under the command of George Bunn, with surgeon J. Dickson. She sailed from The Downs on 23 March 1824, with 172 male convicts.