The work opens with an exhaustive examination of orchestral groups, dividing instruments into strings, wood-wind, brass, plucked strings, and percussion. Each instrument is analyzed according to its range, timbral qualities, registers, and specific scope of expression. The author argues that good orchestration is inseparable from the very soul of the musical work and must follow logical, balanced part-writing rather than arbitrary formulas.
The second chapter focuses on melody, explaining how to make melodic lines stand out naturally through timbre selection, doubling, and register positioning. Various combinations of strings and wind instruments in unison, octaves, thirds, and sixths are thoroughly explored with reference to specific scores. The text emphasizes that individual timbres lose their distinct character when overly doubled and must be handled with care.
The third chapter addresses harmony, establishing fundamental rules for the distribution of notes in chords. Close part-writing is advocated to avoid empty intervals, and methods for overlaying, crossing, and enclosing parts are detailed. The author demonstrates how wood-wind and brass groups can form balanced harmonic bases and how mixed timbres modify resonance.
Subsequent sections examine the composition of the orchestra through full and partial tuttis, transference of phrases, and dynamic gradations like crescendos and diminuendos. The author also explores artificial effects, the role of percussion for rhythm and color, and the principle of economy in orchestral scoring to prevent listener fatigue.
The final chapters provide extensive instruction on combining the human voice with the orchestra, covering solo arias, recitatives, choral accompaniment, and stage instruments. The treatise concludes with a detailed technical review of solo and choral voices, their normal and exceptional registers, and the principles of vocal writing and part combination.
