Frédéric Chopin took the new salon genre of the nocturne, invented by the Irish composer John Field, to a deeper level of sophistication. He was the first to write ballades and scherzi as individual concert pieces. The 21 nocturnes are more structured, and of greater emotional depth. Many of the Chopin nocturnes have middle sections marked by agitated expression (and often making very difficult demands on the performer) which heightens their dramatic character. Nocturne Op. 15 No. 1 in F major is Chopin’s fourth nocturne. It was composed in 1832 in simple ternary form (A-B-A). The first section in F major is marked Andante cantabile while the second section in F minor is fast and dramatic (Con fuoco).