describe the petechial haemorrhages of the lung and swelling of the spleen incident of bubonic plague (Tractatus de Peste, 1629), and early elucidate the empirical method of differential diagnosis for the continental European medical community, and producing the medieval physician and medical scholar Cormac MacDonlevy translator from Latin to vernacular of Bernard de Gordon's Lilium Medicine, Gaulteris Agilon's De dosibus and Gui de Chuliac's Chirurgia. Later in the early 13th century, the O’Donnell also gave succor to the Ó Cléirigh kings of Uí Fiachrach Aidhne. Onara Ultach was descended of the MacDonlevy (dynasty) royals of Ulidia (kingdom), who as above noted after the fall of that Ulster kingdom to the Anglo-Norman forces of Henry Plantagenet served as ollam lieghis or the official physicians to the O'Donnell kings of Tyrconnell. Onara married Donnchadh Ó Cléirigh, a son of the Chief of the name of the Ó Cléirigh family then also of Tyconnell. The Ó Cléirigh were too a learned Irish royal family that had lost their sub-kingdom in Uí Fiachrach Aidhne in what is today County Galway to the Anglo-Norman forces of Henry Plantagenet. The Ó Cléirigh then went into service of the O’Donnell as poet historians, scribes and secretaries or official bards, called in Irish language "ollam righ". Onara bore for Donnchadh a son Mícheál Ó Cléirigh (c. 1590 – 1643), anglicized Michael O’Cleary, who matured to become the principal author of the Annals of the Four Masters. But for the manifold grace of the O’Donnell, this union would never have occurred, and Michael O’Cleary never lived to memorialize this history of Gaelic Ireland. Royal Household The Royal Household was known in Gaelic as "Lucht Tighe" and comprised several offices that were performed on a hereditary basis by the heads and members of particular other families, for over four centuries. Lector & Inaugurator of the Chieftaincy - O'Friel (Ó Frighil) Gallowglass Marshalls & Standard - Bearers - McSweeney (Mac Suibhne) Commanders of Cavalry - O'Gallagher (Ó Gallchobhair) Custodians of the Cathach of St. Columba - Roarty (Mac Robhartaigh) Historians and Scribes - O'Clery (Ó Cléirigh), formerly kings of Uí Fiachrach Aidhne Brehons or Judges - Breslin (Ó Breaslain) Bards & Poets - Ward (Mac an Bhaird) Physicians - Donleavy (Mac Duinnshléibhe), formerly Kings of Ulster (Dál Fiatach of Ulaid) Herenagh of church lands/Custodians of Donegal Castle & Ballyshannon Castle - McMenamin (Mac Meanman) Stockmen/Cattle Drivers - Timoney (Ó Tiománaigh) Later