James Boswell died in 1795 believing he had touched and kissed a cache of Shakespeare's original letters and papers discovered by a Mr. Ireland. His friend, Edmond Malone, publicly exposed the lot as a forgery just a year later.
Matthias OesterreichBorn 1716
Inspector of the Grand Gallery at Sans Souci from 1757 (until his death?).
Life with Boswell:
Oesterreich waited on Boswell at his lodgings in Potsdam on July 4, 1764, and “carried him in a coach to the Retreat of the Great Frederic [i.e. Sans Souci]”, where he gave him a tour of the castle and it's impressive gallery.
Oesterreich compiled several catalogues of the works in the possession of Frederick the Great, some of which are available in various editions via AbeBooks.com today. These include Beschreibung der Königlichen Bildergallerie und des Kabinets im Sans Souci (1764), Beschreibung der Neuen Kammern in Sanssouci (1775) and Beschreibung und Erklärung der Grupen, Statuen, ganzen und halben Brust- Stücke, Basreliefs, Urnen und Vasen von Marmor, Bronze und Bley, sowohl von antiker als moderner Arbeit, welche die Sammlung Sr. majestät, des Königs von Preußen, ausmachen (1775).