Béla Bartók's friendship with violinists Joseph Szigeti and Zoltán Székely allowed him to acquire an in-depth knowledge of the violin that informed his writing. Both Rhapsodies for violin and piano are structured in two parts, a Lassú and a Friss - a Moderato followed by an Allegro. The First Rhapsody draws on Bartok's ethnological studies in it's use of Romanian folk dances, while the Second is a more enigmatic work. The Violin Sonata No. 1 is an earlier piece full of atmospheric drama and grandiose gestures, impressionistic in places and concluding with rich Hungarian folk motifs.