A Mexican Serenade. Joplin's only tango, or with its clear Cuban roots, habañera, is the stunningly beautiful 'Solace' (1909), subtitled "A Mexican Serenade'. With the tempo deliberately marked 'Very slow march time', its gentle chromatic melody and poignant dissonances, all held together over a gently rocking 'ostinato' rhythm, form an expressive gem in the composer's output.