see Poland Street 1 to 8 & 49 to 62 in London Addresses dataset
John Prendergast 50 Poland St ratebooks 1774-7 / SunFire 1778 John Prendergast MD & Honora Morgan widow execs to the will of Jeffrey Morgan Poland St / will PCC of Jeffrey Morgan Esq mentioned house in Bentinck St, St Marylebone, wife Honora, son Jeremiah, brother Charles, John Prendergast of Poland St Doctor of Physic, sister Margaret Broderick, brother in law William Burke, James Henry Burke, cousin James Moore dated 19.9.1777 proved 24.11.1777 / Jeffery Morgan bach of St Marylebone = St Bride Fleet St 2.12.1773 Honora Burke sp otp by lic wits James Henry Burke. John Prendergast / John Prendergast bach Doctor of Physic of Richmond Surrey = St Geo Bloomsbury 12.7.1781 Martha Chase sp otp by lic wits Jos Newton, Mary Ann Chase / will PCC 1804 John Prendergast, Doctor of Physic, Castlebar, County Mayo dated 10.3.1800 mentioned nephew Dr John Prendergast of London friends in England John Bourke & Robert Barnewall proved in Ireland 1803 / will PCC 1808 John Prendergast of Chelsea didn't call himself Doctor