Many of Monteverdi's lost works date from the 1610s and 1620s, and the manuscripts may have disappeared in the wars that overcame Mantua in 1630. Carter cites as a significant aspect of their loss the degree to which they might have provided musical links between the composer's early Mantuan court operas and the public operas he wrote in Venice towards the end of his life: "Without these links ... it is hard to a produce a coherent account of his development as a composer for the stage". In an essay on the opera orchestras of Montverdi's day, Janet Beat regrets that the 30-year gap between "L'Orfeo" and the next Monteverdi opera to have survived, "Il ritorno d'Ulisse in patria", hampers the study of how opera orchestration developed during those critical years.