Can someone kindly explain the science behind the rule that one doesn't blow into (metal) organ pipes, what would be the consequences of doing so, and whether indeed it's sensible to be handling them in the first place?
Widor: second movement of Symphonie VIII. Sounds like Rachmaninov and I'm surprised no-one's mentioned it already. Also: Cochereau/Briggs: Berceuse a la memoire de Louis Vierne. Whitlock: second movement of Sonata Widor: Andante cantabile from Symphonie IV