In this rough reduction sketch, note the inverted arch shapes, short in section A, longer and covering all of section B. The detailed harmonic analysis reflects the importance to the piece's expression of its deceptive progressions and sudden shifts.
A formal Schenker graph bases the opening on the frame ^3-^5, with ^5 appearing first and, as it turns out, remaining primary throughout. The simple ascent is complicated by the C# major displacement with a G# bass -- see the reduction above for details. Since everything is moved down a half-step (from D to C# major), what "should be" ^5 (A5) is now ^5 (G#5). Three notes are affected that way -- I've marked them with asterisks.
As the graph shows, in section B, the lower voice F# moves about neighbors. The orchestral score confirms the meandering of F# about E-E# and G -- see the circled notes in the clarinets, horns, and (at the end) second violins. A particularly pleasing detail is the "piccolo" height ^7-^8 in the flute -- boxed.
