Modulation by chromatic sequences (Romantic style)

When one studies music from a historical and evolutionary point of view, one realizes that most of the apparently new resources are reinventions of older ones.
This is the case in well-established romanticism, in which many techniques are the same but with chromatic treatments or take different directions.
This is the case of the use of sequence. In baroque and classicism we saw sequences that moved within a tonality and also served to modulate neighboring tonalities.
In romanticism a chromatic sequence is applied, especially using dominant chords of all kinds. This chromatic game allows us to “go out” of it towards almost any tonality that we propose. 

Let's see this small example.

The first phrase starts in Am, uses the Neapolitan sixth chord (Bb/D), and repeats the phrase from measure 7.
In measure 11, from V/V (B7), a chromatic sequence with dominants begins: E7 + C#dim7 - D7 + Bdim7, C7 + Adim7, ... We note that each diminished 7 chord is linked to the following one with the first one functioning as dominant of the second. The output is made through the augmented sixth chord toward C maj. But we could have prolonged the sequence and modulated to another key.

In measure 26 another different chromatic sequence begins, in this case with Dis7 chords with chromatic descent of fundamentals: D - C# - C - B - Bb - A - G# resolving to Am.

This is a resource that is frequently seen in Chopin, Brahms, Liszt...