If the 2nd flute has no low B-natural, C-natural be played instead. (3rd movement measure 235 page 91) The part for the bass clarinet is written entirely in the treble clef a major ninth above the actual pitch. Horn parts written in the bass clef sound a fourth higher, never a fifth lower. If the special percussion instruments are not availalbe, the following substitutions may be made: The E-natural for the antique cymbals may be played on a glockenspiel (not the celesta); and The Bb for the small timpano on a side drum with snares silenced, struck with a soft felt stick. Several contrabasses must be provided with means for producing the extra low tones.