Original: Toscanini was often criticized for neglecting American music; however, on November 5, 1938, he conducted the world premieres of two orchestral works by Samuel Barber, Adagio for Strings and Essay for Orchestra.
Simplified: However, in 1938, he conducted the world premieres of two orchestral works by Samuel Barber, Adagio for Strings and Essay for Orchestra (Barber) | Essay for Orchestra.