It is evident that Rinuccini had a high opinion of the value of his libretti. Posterity has awarded the palm, however, to Peri's music. Peri, in his preface to "Eurydice," says he wrote "Daphne" at the suggestion of Corsi and Rinuccini "to test the effect of the kind of melody which they imagined to be the same as that used by the ancient Greeks and Romans throughout their dramas." The success of the private performances of "Daphne" led to the writing of "Eurydice," which was prepared as the festival play for the marriage of King Henry IV., of France, with Mary de Medicis. This work, the first Italian opera, was produced in 1600 in Florence, after careful preparation. Its success was immediate and almost sensational. It was pronounced by all the dilettanti of Florence to be a genuinely new thing in art, and the recitative music, by its fidelity to the text, made a profound impression. Fortunately this work has been preserved and there is a modern reprint of it. In the preface Peri set forth his theory of recitative. It is evident that he had a deep insight into the true nature of the new form. He tried to imitate ordinary conversational speech with music half sung and half spoken--what came to be called "parlando." More complex emotions seemed to him to call for a "melody with greater intervals and a lively tempo, the accompanying instrumental harmonies changing more frequently." It appears also from Peri's preface that he had some assistance from Caccini in writing his score. But, as Rinuccini credits Peri alone with the work, as only Peri's name appeared in the published score, and as Caccini afterward set the entire libretto to music of his own, I suspect that he, being a singer, simply helped Peri with some of the more troublesome parts for the solo voices.