The letters of secret information in the 'Castlereagh Papers,' though assumed by most readers to come from the one source, are divided between two spies. No successful attempt has been hitherto made to identify the writers. The result of Dr. Madden's inquiry went no further than to show that the letters were penned, not by spies of a low type, but by _gentlemen_ of high standing.[742] It was then that I sought to draw aside their masks. 'Downshire's friend' (Turner) was traced more easily than a correspondent of the Home Office, London, whose initial 'O' is dropped once only by Wickham. The spy who contrived to accompany General Tandy's staff in the expedition to Ireland in 1798 has left us a curious account of what passed on board the 'Anacréon'[743] during their brief visit to Ireland. The perilous character of his enterprise was quite as striking as Tandy's descent on Donegal and escape from the English fleet. Wickham confides to Castlereagh merely the initial letter of this spy's name.[744] The written statement from 'O' is a curious document, and one which has been more than once quoted by historians. An old note-book of mine contains the following:--'I have long and vainly tried to discover this man; but to Dr. Madden it will be at least satisfactory to know that "O" can never have taken any prominent part in the councils of the United Irishmen, and his name, even if discovered, would not be a familiar one. He can never have been in the Executive Directory, or on any of the baronial committees. He mentions incidentally that he has been but once in Ireland for eight years.' Some readers fancied that the spy 'O' who accompanied Tandy was O'Herne,[745] O'Finn,[746] Ormby,[747] O'Mealy,[748] O'Hara,[749] O'Neill,[750] O'Connor,[751] or O'Keon[752]; my own theory was that 'O' stood for some man whose name would prove to be Orr. At p. 309, vol. i., of the 'Castlereagh Papers,' in a report of the French fleet preparing to invade Ireland, a list is given of the Irish agents at Brest: 'Orr, _who accompanied Murphy_, was still at Paris.[753] Did not seem to like going.' The letter of 'O,' describing the crew on board the 'Anacréon' in its expedition to Ireland, mentions 'Murphy ... and myself' (p. 407).