HCR diary 13.1.1819 Mrs Opie / Fuseli / Sidney Smith / Samuel Rogers (I just made that note with no more context)
4.4.1823 after seeing Aders' pictures, Sir George Beaumont "proposed bringing Fuseli"
George Beaumont (DNB 1753-1827) and Henry Fuseli (DNB 1741-1825). I've no idea whether Fuseli did visit Aders' collection