Between the Opus number 47, namely Source du Lyson, and the Opus number 52, Le Livre d’or du guitariste, both volumes by Napoléon Coste (1805-1883), there are for other works (from number 48 to 51) in which we find musical gems which are very helpful in developing the knowledge of the own compositional style of Coste.
This volume can be that intermediate step between the exercises included into the Méthode by Sor-Coste and before more complex works such as Études op. 38, Souvenirs. op. 17-23, Source du Lyson and Le Départ op. 31. We underline that the didactical importance of the pieces published in this volume is not only due to their musical writing, which has been focused on a gradual difficulty of the pieces, but also to the chronological order in which they have been composed.
According to Noël Roncet, author of the book Napoléon Coste – Composer, the Six Préludes op. 49 (which are here published as well) have been composed around 1870 whereas the Études op. 38 have been composed in 1873. We can, therefore, say that in those years Coste was developing a writing through which he could have guided the guitarist to read his more complex works.