a) Hearing Tocanini conduct his last concert in Britain - the Brahms 3rd and 4th Symphonies.  B)  Sir Thomas Beecham's first concert at the Festival Hall playing Sibelius's second symphony.  He had been rather sniffy about the hall but this did not stop him giving a brilliant performance.  Thirty odd years later I was driving on the motorway and turned the radio on to find they were playing Sibelius's second.  After about 5 minutes I came to the conclusion it was Beecham's Festival Hal performance I had attended.  It was.