The theme of Handels Chaccone in G Major is simply marked Maestoso, and is eight bars long. This is a contrasting period, with a half-cadence in bar four, and a perfect-authentic cadence in bar eight. The theme consists of quite large block chords in the left hand, with a highly ornamented right hand melody. The theme is in G major.
As with all Theme and Variations, the overall form is ABA’ where B represents a contrasting group of variations that typically change key. One way to categorize Theme and Variations is as Ternary Form, however Ternary can be ABA or AAB, when Theme and Variations can not be AAB. In the case of this work, the B section modulates to the parallel minor of g minor.
The A section consists of all material up through Variation 8. Every variation in this case has the same harmonic progression. The B section consists of Variations 9-16, and finally A’ is Variations 17-21. A really easy way to understand these sections is to look at the key signatures. Despite the fact that the B section modulates though, the variations have a different chord progression.
Here is the progression for the A sections:
M3. vi ii7
M6. IV I6 viio6
Differently, the B section possesses a bass note that descends stepwise creating a harmonic sequence.
Looking back at Variations 1-8, the duration of notes decreases, as the fastest note moves from a quarter note, to triplets, to sixteenth notes in the final variations. Along with this increase, the duration of the variations themselves begin to shorten, likely due to a slightly increased tempo. Starting in variation 3, the triplet motion is in the right hand, while in variation 4, the hands switch and the triplets are in the left hand. Interestingly, the hand with the triplets for these to variations is in the key signature 9/8, while the accompanying hand is in ¾, possibly due to ease of dictating the accompanying hand. For variations 5 and six, the sixteenth notes begin in the right hand, and in the next variation switch to the left hand. Variations 7 and 8 introduce a compound melody that is passed between the hands.
The returning A’ section retains the idea of the compound melody, as it transitions back into G major. The accompaniment becomes far more sparse by simply outlining the chord at the beginning of each measure. The last three variations are a fast sweep of arpeggios that, in variation 19 are in the left hand, in 20 in the right, and in the final 21st variation are in both hands. These arpeggios are sixteenth note arpeggios that begin in parallel movement, though in measure 170 for example begin to move obliquely and conversely.
Overall, this piece begins simply with many ornamentations, at a maestoso tempo. However, as the excitement of the variations build up and the rhythms become more technical, the duration of the variations decreases. In this event, it is definitely possible to just group movements into larger groups based on the rhythms and patterns that they share (for example switching a melody line to the left handfrom right).