orchestra. In an antiphonal section, the composer may have one group of instruments introduce a melodic idea (e.g., the first violins), and then have the woodwinds "answer" by restating this melodic idea, often with some type of variation. In the trio section of the minuet from his Symphony No. 41 (1788), the flute, bassoons and horn exchange phrases with the strings, with the first violin line doubled at the octave by the first oboe: Charles Rosen (1971, p. 240) admires Mozart's skill in orchestrating his piano concertos, particularly the Concerto in E flat major, K482, a work that introduced clarinets into the mix. "This concerto places the greatest musical reliance on tone colour, which is, indeed, almost always ravishing. One lovely example of its sonorities comes near the beginning." The orchestral tutti in the first two bars is answered by just horns and bassoon in bars 2–6. This passage repeats with fresh orchestration: "Here we have the unusual sound on the violins providing the bass for the solo clarinets. The simplicity of the sequence concentrates all our interest on tone-colour, and what follows – a series of woodwind solos – keeps it there. The orchestration throughout, in fact, has a greater variety than Mozart had wished or needed before, and fits the brilliance, charm, and grace of the first movement and the finale." Beethoven Beethoven's innovative mastery of orchestration and his awareness of the effect of highlighting, contrasting and blending distinct instrumental colours are well exemplified in the Scherzo of his Symphony No. 2. George Grove asks us to note "the sudden contrasts both in amount and quality of sound… we have first the full orchestra, then a single violin, then two horns, then two violins, then the full orchestra again, all within the space of half-a-dozen bars." "The scoring, a bar of this followed by a bar of that, is virtually unique, and one can visualize chaos reigning at the first rehearsal when many a player must have been caught unprepared." Another demonstration of Beethoven's consummate skill at obtaining the maximum variety out of seemingly unprepossessing and fairly simple material can be found in the first movement of the Piano Concerto No. 5 in E flat (‘The Emperor’) Opus 73 (1810). The second subject of the sonata form is a deceptively simple tune that, according to Fiske (1970, p. 41) "is limited to notes playable on the horns for