Ist ein Traum/Spür'nur dich".  
He wrote a tone poem in which the theme of the first movement appears in unsion horns and strings before a sequence of trumpet fanfares reaches a climax in G flat in the fourth movement, and another work by this author begins with a unison B-flat held by the horns and woodwinds before they play a B-flat minor descending scale.  This composer of A Hero's Life and An Alpine Symphony wrote an opera in which Herod offers the title character jewels, peacocks, and the sacred veil of the temple instead of the head of the prophet after she dances the Dance of the Seven Veils, and one opera in which Baron Ochs duels Octavian before Sophie and Octavian sing the duet "Ist ein Traum/Spür'nur dich".  For 10 points—name this composer of Salome and Der Rosenkavalier, who wrote a work that begins with a sustained double low C before introducing the three-note "dawn" motif, his tone pome Also sprach Zarathustra.
He wrote a tone poem in which the theme of the first movement appears in unsion horns and strings before a sequence of trumpet fanfares reaches a climax in G flat in the fourth movement, and another work by this author begins with a unison B-flat held by the horns and woodwinds before they play a B-flat minor descending scale.  
Richard {Strauss}